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Car Forum / Driving, Maintenance, Tuning / Maintenance and Repair / February 2006Question on interference engine failure, does this sound right?
I've got a 1995 mitsubishi galant. One owner, one driver, always garaged. Was used as a highway commuter for half it's life, and the other half it mostly sat in the garage (weekend ONLY runabout). It has been extremely well maintained. Up until last week, it still looked and ran like NEW. No rust, no scratches or dents. Always started first try, never gave me any problems. Always got better than 30MPG and had plenty of power. I was in love with that engine, it was really sweet. I had all the belts changed a couple of years ago, including timing and balancer belts. I mention that, so someone won't mistakenly conclude that the engine died of neglect. A few days ago, I was on my way to work, doing about 45MPH in 4th gear (5-speed manual, obviously). Wasn't paying attention to RPM, but the engine (2.4L inline 4-banger) was probably running about 3500RPM, which is about right for the way the car is geared. I'd have normally been in 5th gear, but I was on this little road that I use to cut across from one highway to another, and I've found that by the time I get into 5th is shortly before I have to start slowing down, so I usually just leave it in 4th on that particular little shortcut. About the time I'm thinking that I need to slow down for my turn (I hadn't let off the accelerator yet, but was about to), I heard a fluttering sound. It was kind of like paper flapping in the breeze, very quickly. It was not metallic sounding at all. At the same time, I noticed the engine didn't seem to be pulling anymore. Very shortly afterward (a second, maybe, probably less) the idiot lights lit up to tell me what I already knew . . . the engine had stalled. So I threw the clutch pedal to the floor and coasted around the corner, steering with two hands (no power steering, obviously) and continued coasting down the road a ways until I found a relatively safe place to pull over. I turned off all the electrical stuff (lights, heater fan) because I wasn't sure what was going on yet. I tried starting the car several times. I had plenty of cranking power from the starter, and I actually heard the engine fire a couple of times, but it never actually started. At that point, I was thinking that I'd experienced a rather sudden failure of the fuel pump. I really thought it was starved for fuel, as that's the only thing that made sense, at the time. So I had the car towed to a nearby garage. This garage has a very good reputation, locally, though I've never had any work done there before. It was close, and they are supposed to be good, so that's where I had the car towed. To make a long story short, the best theory as to what happened is . . . balancer belt (2 years old, about 20K miles or so) got loose somehow and managed to get caught under timing belt (also 2 years old, about 20K miles or so) causing the timing belt to slip. Now I don't need an explanation of what an interference engine is and why it's a BAD THING if the timing belt slips. Obviously, if the pistons hit the valves, somethings gotta give. But here's the wierd thing . . . the service manager informs me that 2 of my cylinders compression test at 150 (I'm guessing that's about normal?) and the other 2 cylinders have NO COMPRESSION AT ALL (no reading on the pressure guage) Wouldn't a timing belt slipping cause damage to all four cylinders, if it damaged even ONE of them? If I take the mechanics at their word, it sounds like two cylinders were damaged, but the other two weren't. Is that typical? Now obviously, I need a new (or rebuilt, or used) engine. But I'm trying to understand how the old one failed, and how I could have two cylinders working right (???) and the other two are not??? I'm also wondering how a relatively new balace belt got loose and ended up where it shouldn't have been, but that's an entire other post. On a 4 banger 2 pistons hit top dead center at the same time. This is why the timing can be set 180 out and some will run that way. So yes, 2 can easily be damaged. Mike 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06 http://www.imagestation.com/album/pictures.html?id=2115147590 (More Off Road album links at bottom of the view page) > I've got a 1995 mitsubishi galant. One owner, one driver, always garaged. > Was used as a highway commuter for half it's life, and the other half it [quoted text clipped - 62 lines] > relatively new balace belt got loose and ended up where it shouldn't have > been, but that's an entire other post. > On a 4 banger 2 pistons hit top dead center at the same time. This is > why the timing can be set 180 out and some will run that way. > > So yes, 2 can easily be damaged. > > Mike OK, that makes sense now. It sucks, but what am I going to do about it? I'm heartbroken, as I really loved that engine. I have a feeling the car will never be the same, somehow. :( I'm going to have the engine replaced. I know the car is 10 years old, but it's not your typical 10-year-old car. Overall, it's in about the same condition as most TWO year old cars. Or at least it was before the engine failure. > > On a 4 banger 2 pistons hit top dead center at the same time. This is > > why the timing can be set 180 out and some will run that way. [quoted text clipped - 9 lines] > Overall, it's in about the same condition as most TWO year old cars. Or at > least it was before the engine failure. If you didn't hear a loud bang, 'maybe' the engine is still ok. You might just have a couple bent valves and only need the head reworked. That would be a far cry from the $2500.00 bill you mention to replace it. I think the $1100.00 for the used engine is way too much. I would call up the dealer and ask what their price is for a remanufactured engine. You just need the block and head, the rest can come off your old one. I can get a remanned Jeep engine for $1200.00 or so and I got a 4.2L used engine with 40K on it for mine for $400.00 5 years ago. It is still running really strong. Mike 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06 http://www.imagestation.com/album/pictures.html?id=2115147590 (More Off Road album links at bottom of the view page) > I've got a 1995 mitsubishi galant. I've seen those balancer belts break and fray, but sometimes they don't get tangled up in the timing belt. You really didn't get a very good run on that work, BUT.... if you crashed the valves into the piston tops, you can't really say what the interference gods have in store for you until you open the engine up. The damage could be less, or more, than you have expected. If the mechanic found no compression on two cylinders and good compression on two, there is no second guessing what may have happened. You have to open it up and look. I helped my daughter swap a Japanese used import engine into her car a few years ago, and it worked out pretty well. It was a Mitsubishi also, and the engine was not too expensive ($300 or so at the time). Her old engine was just worn out, not interferenced. The Japanese engine store only had a turbocharged engine, but claimed it would work. It did, with a little modification and swap of parts from her old unturbo-ed engine. We rebelted, reclutched, etc while the engine was out of the car. It was a cheap and satisfactory way to go for her. If you must rely on a mechanic to do your work, you could get into substantial bucks if you are not careful. >> I've got a 1995 mitsubishi galant. > [quoted text clipped - 26 lines] > mechanic to do your work, you could get into substantial bucks if you are > not careful. Yup, it's looking like substantial bucks, all right. My brother was one of the best mechanics in North America (really, he'd won numerous awards). If he was still around, I'm sure he'd be happy to do the work for me. I'm not a mechanic, and I don't play one on TV, either. But from growing up in a household with a good mechanic, I'm not afraid to tackle my own work on the car, even major work. However, I really don't have time to mess with it right now, and the rental car bills are going to pile up on me if I don't get the car back on the road soon. This is what has been proposed, see if this sounds about right . . . The mechanics have located a used engine that they can have shipped in in a couple of days. 66K miles on the engine, $1100, comes with a 1 year/12K mile warranty. With labor and new timing and balancer belts (obviously), they want $2300 total. I asked them about a clutch kit. The clutch never gave me any problems, but the car had over 100K miles on it, and the engine is coming out anyway. They say $250 for the clutch kit. So we're talking US $2550 for a used engine and a clutch kit. I know that's more than the car is worth, but then again, where am I going to find a good reliable used vehicle for less than three grand??? The suspension and brakes are in excellent condition, the tires are new (about 2 months). The car has no problems that I know of other than the non-operational engine. As I wrote earlier, it is 10 years old, but in better condition than most 2-year-old cars, other than the engine, obviously. Two questions: 1) Does that price sound about right, for the engine and labor to install it? 2) Since the engine is coming out anyway, anything I should have done to the car besides the clutch? I was planning to keep the car for about another 6 years. At that point, it -would- have had about 200K miles on it. But now it will have an engine that is slightly newer, I guess. >>> I've got a 1995 mitsubishi galant. >> I've seen those balancer belts break and fray, but sometimes they don't [quoted text clipped - 62 lines] > that is slightly newer, I guess. > I don't see why the shop wouldn't pull the head to see if you just have a couple bent valves. Even a boroscope might be able to determine if there's any piston damage. No matter what you decide to do, make sure the hydraulic timing belt tensioner is also replaced. These may fail after they are compressed once and this may have been the reason the replacement belt failed. Larry > I don't see why the shop wouldn't pull the head to see if you just have a > couple bent valves. Even a boroscope might be able to determine if there's [quoted text clipped - 5 lines] > > Larry Well the shop gave me the option of whether I wanted the head pulled or not. I was told that the job would take several hours, and that the engine probably would need to be replaced anyway. That made sense, seeing as there is a good chance of piston damage. It was a gamble I chose not to take. At best, I would have only saved about 800 bucks by the time the car was back on the road, and that's assuming there was no piston damage. At worst, it would have cost me another 400 bucks or more to learn that the engine needs to be replaced anyway. So I would have been back where I started, but out another 400 bucks or so. And that would have been before I spent a single penny on replacing the engine. I considered taking the engine home to pull the head myself. I briefly considered it, as I really don't have time to do that in the next week or so (with rental car charges piling up), and the wife was less than thrilled with the thought of a broken engine in pieces in our basement. (too cold to work in the garage for the next few months) Basically, I was at a point where I had no good options. I could buy a new car, but don't want the new car payments. Plus, my car insurance is really cheap now, as I don't carry full coverage, as I would HAVE TO, on a new car. I could buy a used car. But, I've already got a used car. And unless I spent significantly more than three grand on a used car, there is no way I'd end up with anything reliable. So looking at my options to get my galant back on the road . . . 1) replacement engine, $2300 by time car is back on the road 2) tear apart current engine to possibly rebuild it, ~$1500 to $2700 -or more- by time car is back on the road Tough choice. I decided if there was a possibility that the repair would cost more than $2300, I might as well take the $2300 option and have some other work done as well. (such as clutch, for example) That way, the extra money I'm spending is actually getting me something in return, other than just more information on why the engine needs to be replaced. In my mind it didn't make much sense to pay someone hundreds of dollars to tell me "Yup, the pistons are damaged". Yeah, there's a possibility of no piston damage, but with my luck, it's likely I've got piston damage. Will have the belt tensioner replaced also. Thanks > > I don't see why the shop wouldn't pull the head to see if you just have a > > couple bent valves. Even a boroscope might be able to determine if there's [quoted text clipped - 9 lines] > I was told that the job would take several hours, and that the engine > probably would need to be replaced anyway. I disagree. It's very unlikely that there's much else wrong other than the bent valves. Pistons might be marked up a bit on the crowns but that won't hurt them. You don't generally get much piston damage from valve contact unless the head of the valve comes off and bounces around down there for a while. There's a slim chance a couple of valve guides might be cracked but that's no big deal. -- Dave Baker >> Well the shop gave me the option of whether I wanted the head pulled or > not. [quoted text clipped - 9 lines] > -- > Dave Baker Yeah, I agree with you, to a point. I understand that there's a chance that the pistons might be OK. But then, even so, I'd only save about $800 on the total repair job, IF the pistons were OK. To me, that $800 is not significant enough to worry about. It's not like I'm made of money or anything, but I had to make some kind of decision. Pulling the head might have cost me even more money in the end, so I decided not to do that. The other thing I had to consider is that rental car charges are piling up fast. (we can't put our lives on hold just because one car is in the shop) So if pulling the head would have added a couple of days to the repair job, then the savings would have been something -less than- $800, as opposed to replacing the entire engine. And again, that's assuming that the pistons are all OK. -Dave > I don't see why the shop wouldn't pull the head to see if you just > have a couple bent valves. Even a boroscope might be able to > determine if there's any piston damage. Of course once they have changed the engine they will attempt to repair it cheaply and at a slack time for the workshop. Once done they will likely sell it as an used engine for $1100. That is what makes them their living. Huw > So we're talking US $2550 for a used engine and a clutch kit. I know that's > more than the car is worth, but then again, where am I going to find a good [quoted text clipped - 3 lines] > As I wrote earlier, it is 10 years old, but in better condition than most > 2-year-old cars, other than the engine, obviously. It's one of the reasons we still have the wife's Beretta for a winter car - the dang thing won't die, and the evil I know is better than an unknown evil. You'll know if $2500 is too much or not. If it feels like it is, then sell the car as-is. If it feels worth it, then do it and don't regret it. It sounds like you like the car, so I'd say do it. > Two questions: > 1) Does that price sound about right, for the engine and labor to install > it? > 2) Since the engine is coming out anyway, anything I should have done to > the car besides the clutch? I'd consider gaskets and stuff to the engine - especially stuff like oilpan gaskets that are a pain to get to in the car, but easily done with the engine on a stand. Frost plugs and block heater? I don't know your car, but I do know that on the wife's car, it was WAY easier to change the steering rack with the engine out - it had a slight leak but would have been a major pain with the engine in the car. I'd pop the hood and look for stuff that looks hard/expensive to change and consider a pre-emptive strike. Ray > Two questions: > 1) Does that price sound about right, for the engine and labor to install > it? > 2) Since the engine is coming out anyway, anything I should have done to > the car besides the clutch? I sometimes tend to live in the past, but that deal doesn't impress me a whole lot. There may be a lot less damage inside that what you are expecting. If the head is not cracked, and the pistons are not damaged, you may be able to clean up the valves and toodle on off. Ideal time to replace the clutch and pressure plate if you have to pull the engine. I cant think of anything else that is really pending. If you have had radiator problems, or expect them, then this could be a good time to take the radiator to the shop for a boilout and repair if there are any leaks. I'm going to look around the net and see what I see on that engine. ¨ The one my daughter and I got from a shop in Houston was much lower mileage, (they claimed), and at a much better price. But that may no longer apply. > Two questions: > 1) Does that price sound about right, for the engine and labor to install [quoted text clipped - 5 lines] > it -would- have had about 200K miles on it. But now it will have an engine > that is slightly newer, I guess. I checked www.car-part.com. There are tons of those engines out there. Some are above $1500, but there a lot of them much less. Some in the $300 range. You would have to shop carefully for something good and near to you. Reemphasize, your engine may not be trashed. I am a little surprised the mechanic automatically assumed it was without opening her up. If you are in a large city, look in the Yellow pages. Lots of people used to import very decent used Jap engines from wrecks. It was said that once a car is wrecked in Japan, it can be more expensive than it is worth to repair it. So these engines were, and probably still are, available from importers at a decent price. How much do you trust that mechanic?? > Reemphasize, your engine may not be trashed. I am a little surprised the > mechanic automatically assumed it was without opening her up. [quoted text clipped - 9 lines] > > How much do you trust that mechanic?? I have no history with the mechanic, but have met him, and he seems nice enough. The garage has a very good reputation, locally. That's GOT to be significant, as it's easy to get a bad rep. doing work like that, and very difficult to get a GOOD rep. I know the engine might not be totally trashed. What I've decided to do is, I've asked a friend of mine to haul the original engine back to my house for me, and I'll store it in our garage. When the weather warms up a bit, I will tear it apart myself to inspect it. If it just needs a valve job, I have a few options at that point. I'll probably just keep it around as a spare engine in case I have another belt failure. I HOPE not, but I wasn't expecting 2 year old belts to fail on me, so . . . Was thinking of giving this car to my niece in four years, when she gets her first license. With minimal work, it will easily last her through college anyway. > To make a long story short, the best theory as to what happened is . . . > balancer belt (2 years old, about 20K miles or so) got loose somehow and > managed to get caught under timing belt (also 2 years old, about 20K miles > or so) causing the timing belt to slip. Brand new belts can break. That's why interference engines aren't worth owning, IMO. Junk design from the get-go. > But here's the wierd thing . . . the service manager informs me that 2 of my > cylinders compression test at 150 (I'm guessing that's about normal?) and > the other 2 cylinders have NO COMPRESSION AT ALL (no reading on the pressure > guage) Not unusual. > Wouldn't a timing belt slipping cause damage to all four cylinders, if it > damaged even ONE of them? Nope. Depends on how fast the camshaft(s) came to a stop relative to the crankshaft, and a lot of random chance on when the valves happen to be open while pistons are coming up. If the break happened at low speed, the cam can stop quickly and only *one* valve out of a whole engine can be damaged. You can even get really lucky and have *no* damage... sometimes. >> Wouldn't a timing belt slipping cause damage to all four cylinders, if >> it damaged even ONE of them? [quoted text clipped - 5 lines] > be damaged. You can even get really lucky and have *no* damage... > sometimes. My Fiero with the 2.5 stripped the timing gear and no damage (well, no damage to anything but the stupid plastic gear.) This was at 75 mph. My mom's 86 Hyundai lost the belt and she lucked out by having the shop just replace the belt without pulling the head... drove it for another couple of years before the oil leaks and rust embarrassed her too much. (it's still in my back yard and would probably start if I put a new battery in it.) THis was in a mall parking lot. Sometimes you get lucky. Sometimes you get stuck with a Hyundai. ;) Ray > >> Wouldn't a timing belt slipping cause damage to all four cylinders, if > >> it damaged even ONE of them? [quoted text clipped - 18 lines] > > Ray And other times, you have a Mercedes diesel that dumps the timing chain under hard acceleration, snapping the camshaft into three pieces and doing unknown other damage that locks the engine so solid that you can't get three degrees of rotation out of the crankshaft using a 10 foot cheater-bar with a 200 pound man bouncing up and down on the end of it. BTDT... Gotta love those interference engines when the timing chain/belt lets go. The results are *SO* predictable: Anything from "replace the belt/chain and drive away", to my scenario above, to "What's this valve doing laying in the bottom of the oil pan? - Oh... same thing these pieces of piston crown are..."  SignatureDon Bruder - dakidd@sonic.net - If your "From:" address isn't on my whitelist, or the subject of the message doesn't contain the exact text "PopperAndShadow" somewhere, any message sent to this address will go in the garbage without my ever knowing it arrived. Sorry... <http://www.sonic.net/~dakidd> for more info >Gotta love those interference engines when the timing chain/belt lets >go. The results are *SO* predictable: Anything from "replace the >belt/chain and drive away", to my scenario above, to "What's this valve >doing laying in the bottom of the oil pan? - Oh... same thing these >pieces of piston crown are..." Twenty years ago, I was a poor, starving college student with access to the department machine shop. A friend of the family bought a 1982 Ford Escort. After about 15,000 miles, the timing belt broke. Ford was very good and replaced it under some sort of warranty. At 40,000 miles or so, the timing belt broke again, and they paid to replace the engine. Come around 60,000 miles, the timing belt broke a third time, and they gave me the car. I called around to junkyard, and everybody had a bunch of '82 Escorts on the lot, but nobody had one with a good cylinder head. This was a sign. I actually rebuilt the head and put oversized valves in, which was an awful lot of work and I learned a whole lot about machine shop work in the process. I got about 10,000 miles out of the thing before, with no warning, the timing belt broke. I gave it to a friend of mine who was a mechanic and he rebuilt it and gave it to his daughter, who got around 12,000 miles. This is a clear example of good money after bad. --scott Signature"C'est un Nagra. C'est suisse, et tres, tres precis." >> To make a long story short, the best theory as to what happened is . . . >> balancer belt (2 years old, about 20K miles or so) got loose somehow and [quoted text clipped - 5 lines] > >> But here's the wierd thing . Not wierd at all. > . . the service manager informs me that 2 of my >> cylinders compression test at 150 (I'm guessing that's about normal?) and >> the other 2 cylinders have NO COMPRESSION AT ALL (no reading on the pressure >> guage) YOU CANNOT RUN A MEANINGFUL COMPRESSION TEST ON AN ENGINE WITH NON-OPERATIVE VALVES!! The timing belt broke, the camshaft is NO LONGER TURNING! Some valves are open (no compression) some are not. Some cylinders will have compression, some will not. Take the valve cover off and turn the cam and you will get a completely different set of compression readings. While doing that it is V ERY easy to inspect for bent valves WITH THE CYLINDER HEAD STILL ON THE VEHICLE. The bent valves will remain lower than the others. It is very easy to see. Get the car out of that shop and take it somewhere that has competent techs. I have seen more than one Galant drive away with perfect cylinder balance/compression after the timing belt broke on its allegedly interference engine and ALL we did was replace the timing belt, balance shaft belt, cam, crank, balance shaft seals, water pump and tensioners. Don www.donsautomotive.com >Not unusual. >> [quoted text clipped - 6 lines] >the cam can stop quickly and only *one* valve out of a whole engine can >be damaged. You can even get really lucky and have *no* damage... sometimes. > >> To make a long story short, the best theory as to what happened is . . . > >> balancer belt (2 years old, about 20K miles or so) got loose somehow and [quoted text clipped - 16 lines] > NON-OPERATIVE VALVES!! The timing belt broke, the camshaft is NO > LONGER TURNING! AIUI from the OP's post the belt just slipped rather than breaking although by how many teeth is unknown. However it's all a bit odd. If it slipped enough to cause some valves to hit (usually exhaust ones if a belt slips and cam timing gets retarded) then all cylinders should have been affected equally. It's also not sensible to run a compression test on an engine if the cam timing is known to be out and risk more internal damage than was there to start with. It may be worth fitting a new belt correctly timed and then checking compressions if the labour charge isn't excessive before assuming that anything is in fact bent. Also as you say, a quick look under the rocker cover can often identify badly bent valves as can checking the valve clearances if the engine has solid lifters rather than hydraulic. A leakdown test with compressed air is of more value than a compression test in such cases and safer as it doesn't require the engine to be cranked over. -- Dave Baker > YOU CANNOT RUN A MEANINGFUL COMPRESSION TEST ON AN ENGINE WITH > NON-OPERATIVE VALVES!! Don is right on the nose on this one. BUT, I had assumed the mechanic had replaced the belts, rephased everything, and had the valve train working before he tried to run a compression test. If he didn't, he is not competent to do this sort of work, and you should run, not walk, away from his shop. >> YOU CANNOT RUN A MEANINGFUL COMPRESSION TEST ON AN ENGINE WITH >> NON-OPERATIVE VALVES!! [quoted text clipped - 7 lines] > run, > not walk, away from his shop. Yes. It was fitted with new belts before the compression test was done. It was actually running on 2 cylinders. The mechanic noticed right away that it wasn't running right. Thus, the compression test. > >> YOU CANNOT RUN A MEANINGFUL COMPRESSION TEST ON AN ENGINE WITH > >> NON-OPERATIVE VALVES!! [quoted text clipped - 11 lines] > was actually running on 2 cylinders. The mechanic noticed right away that > it wasn't running right. Thus, the compression test. Ok, I am playing the devil's advocate here, but.... In order to tell if the engine has damage, they must do one simple test, pour oil into the cylinders. If the oil stays put, there is a 99% chance the engine is fine. If there is a hole in the piston, the oil will run away instantly. To test the valves all they have to do is remove the valve cover and look at the valve clearance. Not remove the head, just the cover! They did neither of these things and that just SCREAMS Rip Off to me. Big time! To 'fake' a dead engine, all they have to do is put the belts on slightly wrong either 'accidentally' or on purpose. Sorry man, but I really think you are getting ripped off. I would 'highly' recommend you get a second opinion before getting suckered for $2500.00. My $0.02, Mike 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06 http://www.imagestation.com/album/pictures.html?id=2115147590 (More Off Road album links at bottom of the view page) >> >> YOU CANNOT RUN A MEANINGFUL COMPRESSION TEST ON AN ENGINE WITH >> >> NON-OPERATIVE VALVES!! [quoted text clipped - 32 lines] > To 'fake' a dead engine, all they have to do is put the belts on > slightly wrong either 'accidentally' or on purpose. Maybe I'm a dumbass Mike, but why don't you explain to me how they could kill 2 cylinders by putting the belt on a tooth ot two out of time? Bob > Sorry man, but I really think you are getting ripped off. > > I would 'highly' recommend you get a second opinion before getting > suckered for $2500.00. > > My $0.02, > Maybe I'm a dumbass Mike, but why don't you explain to me how they could > kill 2 cylinders by putting the belt on a tooth ot two out of time? > Bob Likely the same way only 2 cylinders can show 0 compression. If the belt slipped enough to punch out pistons or bend valves, how come it only did 2? He stated he cranked it trying to start it after it stalled. I don't know the cam timings to explain it, but I have seen engines missing compression only in a couple cylinders when the belt is on wrong. Mike 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06 http://www.imagestation.com/album/pictures.html?id=2115147590 (More Off Road album links at bottom of the view page) > I don't know the cam timings to explain it, but I have seen engines > missing compression only in a couple cylinders when the belt is on > wrong. That's from the engine turning over when the belt is broken or missing. If it were caused by it being installed wrong all of either the intake or the exhaust valves would be bent and none of the cylinders would have any compression. Bob > Likely the same way only 2 cylinders can show 0 compression. If the > belt slipped enough to punch out pistons or bend valves, how come it > only did 2? Because that is what happened. Worked on a 97 Catera last week, timing belt broke, bent all the valves on the right side of the engine, left side is fine. >> Likely the same way only 2 cylinders can show 0 compression. If the >> belt slipped enough to punch out pistons or bend valves, how come it [quoted text clipped - 4 lines] > Worked on a 97 Catera last week, timing belt broke, bent all the > valves on the right side of the engine, left side is fine. I wish Mike could have seen what all was involved in repairing that one. He seems to think a repair like that can be done for $100....lol Bob >>Maybe I'm a dumbass Mike, but why don't you explain to me how they could >>kill 2 cylinders by putting the belt on a tooth ot two out of time? [quoted text clipped - 4 lines] > only did 2? He stated he cranked it trying to start it after it > stalled. Because the belt passed through the maximum interference phasing just as two pistons smacked valves, then came to rest at a non-interference phasing? Who really knows. The process of a belt breaking or even slipping is dynamic- the cam and crank phasing vary as the incident happens. A belt installed wrong results in a static timing offset. > I don't know the cam timings to explain it, but I have seen engines > missing compression only in a couple cylinders when the belt is on > wrong. Impossible. If the belt is on wrong (and there's no other damage) then all cylinders WILL be affected equally. End of story. >>>>YOU CANNOT RUN A MEANINGFUL COMPRESSION TEST ON AN ENGINE WITH >>>>NON-OPERATIVE VALVES!! [quoted text clipped - 18 lines] > chance the engine is fine. If there is a hole in the piston, the oil > will run away instantly. You're must making stuff up, now. I've never heard of anyone "testing" an engine that way. Compression or leakdown to check valve seal, followed by head removal (to repair the bad valves) and visual inspection of pistons is the norm. They should also check the TDC height of the each piston as the engine is rotated, because these little Japanese engines sometimes bend connecting rods instead of holing the pistons. > YOU CANNOT RUN A MEANINGFUL COMPRESSION TEST ON AN ENGINE WITH > NON-OPERATIVE VALVES!! I would assume they slapped a new rubberband on the thing and THEN checked compression. That's what I'd do in their place. >> YOU CANNOT RUN A MEANINGFUL COMPRESSION TEST ON AN ENGINE WITH >> NON-OPERATIVE VALVES!! > > I would assume they slapped a new rubberband on the thing and THEN checked > compression. That's what I'd do in their place. yup, that's what was done. New rubber bands. :) >> YOU CANNOT RUN A MEANINGFUL COMPRESSION TEST ON AN ENGINE WITH >> NON-OPERATIVE VALVES!! > >I would assume they slapped a new rubberband on the thing and THEN >checked compression. Perhaps so -- there was no mention of it that I saw, however. > That's what I'd do in their place. Not me, I would remove the valve cover, rotate the camshaft (first turning the crank where to where are no pistons at TDC) and and see if all the valves close properly. If a valve gets bent it is usually very easy to see. Don www.donsautomotive.com >YOU CANNOT RUN A MEANINGFUL COMPRESSION TEST ON AN ENGINE WITH >NON-OPERATIVE VALVES!! The timing belt broke, the camshaft is NO [quoted text clipped - 10 lines] >timing belt, balance shaft belt, cam, crank, balance shaft seals, >water pump and tensioners. Ditto. In my family we have gotten lucky in the past. We snapped a belt and let the car coast to the side of the road. I thought it was bad news when I found out it was an interference engine. figureing it couldn't hurt, I put in a new timing belt and hit the starter. The car fired right up and ran fine until we sold the car about a year and 10k miles later. --------------- Alex Have them pull the head FIRST. You probably can just replace a couple valves or replace the head itself. Much faster repair and MUCH MUCH cheaper. No need to replace the engine unless it actually punched a hole in a piston or damaged the bore. Keep in mind the "new" engine could have many more issues than the one you have. Price wise I can find at least 25 2.4s for under 800.00 all over the country. Not sure where you are but punch up http://www.car-part.com/ for some ideas on prices. SignatureSteve Williams > I've got a 1995 mitsubishi galant. One owner, one driver, always garaged. > Was used as a highway commuter for half it's life, and the other half it [quoted text clipped - 62 lines] > relatively new balace belt got loose and ended up where it shouldn't have > been, but that's an entire other post. Seconded, fix it, no big deal a couple of valves, but see what caused the failure of course. > Have them pull the head FIRST. You probably can just replace a couple > valves or replace the head itself. Much faster repair and MUCH MUCH [quoted text clipped - 120 lines] > ----= East and West-Coast Server Farms - Total Privacy via Encryption > =---- > Seconded, fix it, no big deal a couple of valves, but see what caused the > failure of course. Yup, as I wrote elsewhere, pulling the head might have saved me only about $800 at most, and that's before rental car charges were figured in. A couple of days longer in the shop (to pull the head, have the head rebuilt, etc.), and the savings might have been ($800 minus increased rental car charges). It was a tough decision, but I decided to replace the engine. Again, it was a tough decision. But sheesh, I had to make some kind of decision. So, the engine goes. :( -Dave > > Seconded, fix it, no big deal a couple of valves, but see what caused the > > failure of course. [quoted text clipped - 6 lines] > Again, it was a tough decision. But sheesh, I had to make some kind of > decision. So, the engine goes. :( -Dave You should have read this thread properly. You only have to remove the valve cover to inspect the valves. This takes 10 minutes. They cannot have tested the compression with a broken belt. The numbers only mean the mechanic is a liar and a crook. They are incompetent, you need to 'run' away from this shop. The fix is likely less than $100.00.... Sheesh......... You are getting 'suckered'!!!! Mike 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06 http://www.imagestation.com/album/pictures.html?id=2115147590 (More Off Road album links at bottom of the view page) > You should have read this thread properly. > > You only have to remove the valve cover to inspect the valves. This > takes 10 minutes. > > They cannot have tested the compression with a broken belt. What makes you think they did? > The numbers > only mean the mechanic is a liar and a crook. [quoted text clipped - 8 lines] > > Mike No but another mechanic is getting shitcanned by a moron without all the facts. And what shop do you of know that will fix bent valves or even replace a timing belt for under $100? Bob >> Don wrote: >> [quoted text clipped - 6 lines] > > yup, that's what was done. New rubber bands. :) Ok, then lets start with some 'facts'. He has a slipped or broken timing belt. To test the compression, the valve cover 'must' be taken off to reset the belt first. This means the valve stems are visible. This means the valve lash is visible. A valve bent bad enough to cause 0 compression must show a lash issue. If they did not remove the valve cover and they checked the compression with the slipped or broken belt, then 100% FOR SURE he is being ripped off! A slipped belt can easily give 0 compression on 2 cylinders. A belt put on improperly, by 'accident' for sure eh..., can also show 0 compression on 2 cylinders. If they don't know how to check for a bent valve by checking the lash, then they are not competent enough to do the work. The sparkplugs were removed to check the compression. This means the top of the pistons are visible through the spark plug hole. Usually just a flashlight is enough to see the piston tops, but a good shot of oil onto the top of the piston will tell immediately if there is a hole in the piston causing 0 compression. The oil will run away instantly. If the oil stay put, the engine is likely just fine. If they cannot see in there or don't have the equipment to look in there or couldn't be bothered to do a standard wet test, then they are not competent enough to do the job or are pure rip off artists. So in my opinion, either they are just plain incompetent or they are a bunch of crooks. Mike > > You should have read this thread properly. > > [quoted text clipped - 35 lines] > > > > yup, that's what was done. New rubber bands. :) > Ok, then lets start with some 'facts'. > > He has a slipped or broken timing belt. HAD is the key word here, the mechanic put a new belt on and then checked compression. > To test the compression, the valve cover 'must' be taken off to reset > the belt first. This means the valve stems are visible. This means the > valve lash is visible. There are some engines out there which require valve cover removal as part of a timing belt job. A 95 Mitsibishi with a 2.4 isn't one of them. > A valve bent bad enough to cause 0 compression must show a lash issue. > [quoted text clipped - 5 lines] > on improperly, by 'accident' for sure eh..., can also show 0 compression > on 2 cylinders. No it can't, if the belt slipped enough to bend 2 exhaust valves it would have bent ALL the exhaust valves. > If they don't know how to check for a bent valve by checking the lash, > then they are not competent enough to do the work. [quoted text clipped - 14 lines] > > Mike The fact is you're opinion is based on things you don't know much about. Bob >> > You should have read this thread properly. >> > [quoted text clipped - 35 lines] >> > >> > yup, that's what was done. New rubber bands. :) > > Ok, then lets start with some 'facts'. > > [quoted text clipped - 22 lines] > No it can't, if the belt slipped enough to bend 2 exhaust valves it would > have bent ALL the exhaust valves. Right, so it likely has only slipped enough to kill the compression on those two rather than punch out things... > > If they don't know how to check for a bent valve by checking the lash, > > then they are not competent enough to do the work. [quoted text clipped - 17 lines] > The fact is you're opinion is based on things you don't know much about. > Bob If it smells, well... Mike > >> > You should have read this thread properly. > >> > [quoted text clipped - 35 lines] > >> > > >> > yup, that's what was done. New rubber bands. :) >>Seconded, fix it, no big deal a couple of valves, but see what caused the >>failure of course. [quoted text clipped - 6 lines] > Again, it was a tough decision. But sheesh, I had to make some kind of > decision. So, the engine goes. :( -Dave You are getting your old engine back, right? >> Yup, as I wrote elsewhere, pulling the head might have saved me only >> about $800 at most, and that's before rental car charges were figured in. [quoted text clipped - 5 lines] > > You are getting your old engine back, right? Yup. Will tear the head off to inspect it when the weather is warmer. * You can't due a compression test on an engine with a broken timing belt! Totally meaningless. Ths shop is clueless if they think they can. * Many engines that the book says are interference engines are not. Yours almost certainly is not. I have replaced broken timing belts on a great many "interference" engines that suffered no damage whatsoever. Many of the guides appear to be paranoid. * Checking for bent valves requires the removal of the valve cover only. I do it all the time. Turn the crankshaft in between top and bottom dead center so no pistons are all the way up. Rotate the camshaft and look for something like normal valve lash. Bent valves will be visibly lower and the valve train obviously very loose. * Take the car out of that shop and take it to somebody who knows how to fix it. Almost certainly it just needs the T-belt job done over. Don www.donsautomotive.com > * You can't due a compression test on an engine with a broken timing > belt! Totally meaningless. Ths shop is clueless if they think they > can. I suspect they threw a belt on.. personally, I generally remove the rocker arms and do a leakdown test. > * Many engines that the book says are interference engines are not. > Yours almost certainly is not. I have replaced broken timing belts on > a great many "interference" engines that suffered no damage > whatsoever. Many of the guides appear to be paranoid. Gates calls that engine an interference engine.. I take that to mean that the piston can come up and smack the valve.. doesn't mean it will. A non-interference engine won't hurt the valves. When a customer comes in on the hook and it's a borken timing belt on an interference engine I tell them that there's a possibility of valve damage. If it's listed as a non-interference engine I tell them that it's likely only to need a timing belt. > * Checking for bent valves requires the removal of the valve cover > only. I do it all the time. Turn the crankshaft in between top and > bottom dead center so no pistons are all the way up. Rotate the > camshaft and look for something like normal valve lash. Bent valves > will be visibly lower and the valve train obviously very loose. Agreed.. I still like to do a modified leakdown test though.. but bent valves are sometimes pretty obvious. > * Take the car out of that shop and take it to somebody who knows how > to fix it. Almost certainly it just needs the T-belt job done over. I don't diagnose long distance.. I don't badmouth other shops unless I'm positive I know what's going on.. Jim Eric B. Wrote: > I've got a 1995 mitsubishi galant. . Really, I am not kidding, that is the real problem. SignatureDieInterim http://www.automotiveforums.com |
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