 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
Car Forum / GMC Cars / October 2005Brake caliper mounting question
While replacing brake pads on a 94 Grand Am, one of the driver-side caliper mounting bolts -- the thread on the mounting bracket, rather -- got stripped before reaching the torque specs. I thought I could use a HeliCoil insert, but was advised against it, as there was "too much pressure" there which would break the HeliCoil. I ended up installing a universal GM oversized caliper mounting bolt. The problem is that the bolt seems to be slightly longer and reached the bottom of the hole before it could get fully seated on the outside of the stabilizer. So there's a little slack (probably .5 to 1.0 mm) when I try shaking the caliper. How unsafe is that? I know that bolt is not going anywhere, it took some monstrous torque to get it to where it is. But still, I'd like to be sure that I'm not missing something. And I'm trying to avoid replacing the whole mounting bracket because of a stripped thread. Thanks. Svilen If you don't mind my asking did you drill and tap the stripped hole to accept the threads of the oversized bolt? > While replacing brake pads on a 94 Grand Am, one of the driver-side > caliper mounting bolts -- the thread on the mounting bracket, rather -- [quoted text clipped - 11 lines] > Thanks. > Svilen > If you don't mind my asking did you drill and tap the stripped hole to > accept the threads of the oversized bolt? I had that question too. And if the bolt was too long why not grind or cut off the excess so it would seat properly. To answer your question it's not going anywhere. >>If you don't mind my asking did you drill and tap the stripped hole to >>accept the threads of the oversized bolt? > > I had that question too. And if the bolt was too long why not grind or > cut off the excess so it would seat properly. > To answer your question it's not going anywhere. The bolt is one of those self-threading oversized ones that NAPA and other places sell, to help guys that mess up like I did. When I compared the oversized bolt to the original one, they seemed of an equal length. What I should have accounted for is the excess material that the bolt cuts making its way in. It's got to go somewhere, and probably that's what's preventing the bolt from going all the way in. > If you don't mind my asking did you drill and tap the stripped hole to > accept the threads of the oversized bolt? No, I didn't drill and tap. The bolt I installed is one of those self-threading ones that NAPA and other places sell. >>While replacing brake pads on a 94 Grand Am, one of the driver-side >>caliper mounting bolts -- the thread on the mounting bracket, rather -- [quoted text clipped - 11 lines] >>Thanks. >>Svilen If it were mine I would unscrew the bolt, clean out the threads in the hole and put it back together again. Surely screwing it in the second time wouldn't be as difficult would it? Or is the bolt a one time-use only deal? But that's just me being anal. It would bug the heck out of me thinking about all the ways that the existing situation might cause a serious braking problem down the road even if those possibilities are only remote or even nonexistent. Peace of mind. >> If you don't mind my asking did you drill and tap the stripped hole to >> accept the threads of the oversized bolt? [quoted text clipped - 19 lines] >>>Thanks. >>>Svilen > If it were mine I would unscrew the bolt, clean out the threads in the hole > and put it back together again. Surely screwing it in the second time > wouldn't be as difficult would it? Or is the bolt a one time-use only deal? Yes, it's one of those -- per the directions on the box, it is not recommended for reuse. And I'm not sure if a new one of those would work, if I unscrewed this one and cleaned up the whole. I was hoping I'd find someone here that has had experience with those oversize bolts. > But that's just me being anal. It would bug the heck out of me thinking > about all the ways that the existing situation might cause a serious braking > problem down the road even if those possibilities are only remote or even > nonexistent. Peace of mind. Agreed. It's bugging me already, more so that it's my son's car. That's why I'm asking. >>>If you don't mind my asking did you drill and tap the stripped hole to >>>accept the threads of the oversized bolt? [quoted text clipped - 19 lines] >>>>Thanks. >>>>Svilen you can helicoil it. A helicoil will hold way more pressure than you think. I have installed a good thousand of them in fighter aircraft and the brake system is one of the places we install them in. Never seen one break from too much pressure yet. Normally the bolt will break before the insert. Just make sure you get Heli-coil Brand and not a cheap knock off. And get a free running. If you run a screw locking you will need a good quality bolt and not a parts store cheepo. As for them breaking with too much pressure. That is complete BS. The only thing you shouldn't use them for is when the parent threads need to seal a fluid with any pressure. > While replacing brake pads on a 94 Grand Am, one of the driver-side > caliper mounting bolts -- the thread on the mounting bracket, rather > -- got stripped before reaching the torque specs. I thought I could > use a HeliCoil insert, but was advised against it, as there was "too > much pressure" there which would break the HeliCoil. I ended up > installing a universal GM oversized caliper mounting bolt. There is nothing wrong with using a helicoil. They are as strong or stronger then the original thread. I certainly wouldn't be using some sort of oversize universal bolt. These are brakes that we are talking about. Just fix it right. If you don't feel comfortable with the helicoil, then install a new spindle, or go get yourself one from a wrecking yard. Ian he probably means oversized threads.not the bolt itself?as long as it is tapped out right it is best fix.boy,a picture is worth a thousand words!!!!!!!!! |
Reply to this Message |
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2008 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.