even after extensive driving the gauge does not come up above the C
mark. the heater is also not putting out as it should. outdoor temps
are cold (in northern virginia). just got home after a 20 mile drive
in 45 degree weather and can pit my hands on anything under the hood
and barely detect any heat.
coolant levels in the radiator and overflow are normal and i checked
the coolant and it is registering ok for minus 34 F.
just replaced the water pump 2 yrs ago & it is not leaking. so...my
questions are...
thermostat needs replacing?
or could it be something else?
what are the consequences of driving it for a couple more days like
this?
how difficult is it to replace the themo on this model. 93 XLT, 6
cylinder, 3.0 L
i used to have a 64 MGB and was a pro at replacing starters and
maintaining it but have never done any work on this truck.
thanks from a gal in virginia!
suzi g
Jeff Strickland - 18 Dec 2007 20:11 GMT
Remove the radiator cap and start the motor.
If the fluid moves, the tstat is already open, and the temps will remain low
in this case. You need to replace the tstat to correct this. If the fluid
does not move, even when the motor should be up to temp (you must carefully
remove the cap on a hot motor, or leave the cap off and wait for the engine
temp to rise, but you will have difficulty noticing any difference in hot
and cold performance in that case), then your water pump is likely to be
worn.
Some water pump makers use a plastic impeller (the part that actually moves
the coolant), and the impeller blades can wear down. In this case, the water
does not circulate well, and the heater remains cold even after the motor
should have heated up.
In cold weather, there can be sufficient airflow around the motor to keep it
reasonably cool -- if not outright cold -- even if the water pump is not
pumping water. Odds are against this, but it could happen. If the tstat
remainedj open at all times, the coolant would constantly circulate and
never get hot enough for the heater to give you any heat. I think your tstat
is toast (stuck open) as my first choice, and the water pump impeller is
worn down as my second.
> even after extensive driving the gauge does not come up above the C
> mark. the heater is also not putting out as it should. outdoor temps
[quoted text clipped - 21 lines]
>
> suzi g
ds549@webtv.net - 18 Dec 2007 22:05 GMT
yep, thermostat may fix er right up/ get the 190's dgree one
,lucas
http://www.minibite.com/america/malone.htm
IYM - 19 Dec 2007 12:32 GMT
Sounds like your thermostats stuck open....
Better to be stuck open than closed though!! At least you can drive it to
get parts!
IYM
> even after extensive driving the gauge does not come up above the C
> mark. the heater is also not putting out as it should. outdoor temps
[quoted text clipped - 21 lines]
>
> suzi g
suzikg - 20 Dec 2007 22:30 GMT
Thanks to all for your responses,
I did all of the diagnostics on it myself (with your help) & decided
it was the thermostat. It was the original on my truck with 205K
miles on it...gotta love my Ranger. Parts were under $10 & had to
replace some coolant lost during the interchange but a real cheap
repair.
It's working like a charm and the heater is blasting me out now. No
more freezing fingers and toes :).
Again, thanks to everyone and have a great holiday season!!!
suzi g
Jeff Strickland - 20 Dec 2007 23:12 GMT
File that one away for future reference ...
Tstat stuck open = cold.
You should see a bit better fuel mileage now as well. A cold motor will be
detected by the engine management computer, and it will set the mixture rich
(more fuel than air). Rich and Lean refer to the ratio of fuel and air. A
cold motor will run rich because in the old days of carburators and chokes,
one would set the choke so the cold engine would fire. Setting the choke was
equivelent to mechanically holding the air intake closed while the fuel pump
continued to add gas. Once the motor fired, the driver would set the choke
off, allowing more air into the fuel mixture. You do not have a choke
anymore, but the computer accomplishes the same task by adding more gas via
setting the injector timing longer. Once the motor heats up, the injector
timing is returned to normal, but your engine never reached normal temp so
the injector timing remained set long, causing you to use more fuel than you
otherwise might have expected.
Now that the motor gets hot, the computer knows and can set the injectors to
the normal duty cycle. Two birds with one stone ...
> Thanks to all for your responses,
>
[quoted text clipped - 10 lines]
>
> suzi g