Hey, I have just purchased a 93 Saturn SC2 DOHC. I only paid 700 so I
expected some glitches, but the previous owner didn't mention anything about
it overheating. I took it to a MIDAS and they tested it and put about 350
dollars in it to stop it from overheating and it is still doing it. Here is
what I know:
Midas replaced the thermostat and bypassed the sensor that kicks the fan on,
because it didn't seem to be working, they installed a switch that leaves the
fan on constantly while the car is on. They pressure tested the entire system
and there are no leaks. Fluid is pumping through it fine, so the water pump
appears to be fine.
If I start it up and let it sit, it goes to about the half way mark on the
heat gauge and stays there and does not overheat. But once I start to drive
it, it creeps above half way mark untill I stop at a stop sign or traffic
light and then the heat gauge creeps up to the 3/4 mark and higher, that is
when the overfill tank starts to overfill and sprays the engine with coolant
and I start to get steam/smoke from the coolant on the engine.
So far it hasn't hit the actual red indicator on the gauge but it gets close
enough and the overfill tank starts releasing coolant. The coolant indicator
light just started comming on last night, but I think it is because I am low
on coolant from it comming out of the overfill tank.
Midas thinks it is an electrical problem, but since they bypassed the fan,
what other electrical components are involved with the coolant system. I have
had vehicles in the past overheat and have had head gaskets blown because of
it. So I don't want to take any chances, but I am also not convinced it is an
electrical problem, although to be honest I do not know what all electrical
components are involved.
PLEASE HELP and provide any suggestions or tips you can think of. This is the
only transportation I have to get to work and need it to last at least a few
months till tax return.
I thank you in advance for any suggestions or advice you can give,
Tim
Edwin Pawlowski - 22 Oct 2006 18:13 GMT
> Hey, I have just purchased a 93 Saturn SC2 DOHC. I only paid 700 so I
> expected some glitches, but the previous owner didn't mention anything
[quoted text clipped - 3 lines]
> is
> what I know:
Most of the big chains are high priced and mediocre as far as real repairs
go. Mufflers, yes, anything else, find a competant garage.
>Fluid is pumping through it fine, so the water pump
> appears to be fine.
[quoted text clipped - 8 lines]
> coolant
> and I start to get steam/smoke from the coolant on the engine.
> Midas thinks it is an electrical problem, but since they bypassed the fan,
> what other electrical components are involved with the coolant system.
The Midas cash register. They want to touch more of your gold.
> I am also not convinced it is an
> electrical problem,
Neither am I. If the T'stat is working and the water pump is pumping, you
have to wonder about water flow and heat transfer.
How was the pump tested? Under a higher load, a radiator hose may be
collapsing and causing a restriction. There may be gunk in the engine block
that is restricting some passages.
Skip Midas and find a good local guy. When you do, stick with him.
Mike Marlow - 22 Oct 2006 18:57 GMT
> Midas replaced the thermostat and bypassed the sensor that kicks the fan on,
> because it didn't seem to be working, they installed a switch that leaves the
> fan on constantly while the car is on. They pressure tested the entire system
> and there are no leaks. Fluid is pumping through it fine, so the water pump
> appears to be fine.
First mistake - taking the car to Midas. They should stick to mufflers.
The evidence is in their fix - installing a switch instead of fixing the
problem.
> If I start it up and let it sit, it goes to about the half way mark on the
> heat gauge and stays there and does not overheat. But once I start to drive
> it, it creeps above half way mark untill I stop at a stop sign or traffic
> light and then the heat gauge creeps up to the 3/4 mark and higher, that is
> when the overfill tank starts to overfill and sprays the engine with coolant
> and I start to get steam/smoke from the coolant on the engine.
Is the radiator clean? By that I mean is it clean between all of the
cooling fins? Does it have the right radiator cap on it?
> Midas thinks it is an electrical problem, but since they bypassed the fan,
> what other electrical components are involved with the coolant system.
Let's see - the coolant is circulating and the fan is running full time.
Yup - must be an electrical problem. Sorry - don't mean to give you a hard
time, but get yourself a real mechanic and not the guys at Midas.

Signature
-Mike-
mmarlowREMOVE@alltel.net
Brian - 22 Oct 2006 23:18 GMT
> If I start it up and let it sit, it goes to about the half way mark on the
> heat gauge and stays there and does not overheat. But once I start to
[quoted text clipped - 5 lines]
> coolant
> and I start to get steam/smoke from the coolant on the engine.
This is a longshot:
You may have a minor flaw in the head gasket which doesn't show up until (1)
the engine is warmed up and (2) there is enough pressure in the exhaust
stream (ie: engine operating under load and not just sitting idle) to cause
some leakage of exhaust gasses into the coolant jacket. This would drive
the pressure in the coolant system way up, resulting in spill-over from the
coolant tank, and significant loss of coolant efficiency - your overheating
problem.
Good Luck
B.
Jody Lee Bruchon - 22 Oct 2006 23:55 GMT
> If I start it up and let it sit, it goes to about the half way mark on the
> heat gauge and stays there and does not overheat. But once I start to drive
> it, it creeps above half way mark untill I stop at a stop sign or traffic
> light and then the heat gauge creeps up to the 3/4 mark and higher, that is
> when the overfill tank starts to overfill and sprays the engine with coolant
> and I start to get steam/smoke from the coolant on the engine.
Perhaps there is air in the system. I have a 1990 Beretta GT with a
metal hose coming off the top of the water pump and that hose has a tiny
bleeder screw on the top. I didn't know better, so I fixed where that
hose's gasket failed and drove the car--which promptly overheated. I
had let out the coolant in the pump to drain some gasket material that
fell into the pump when I removed the hose, and didn't know I needed to
bleed the thing afterwards.
It's probably not correct, but I don't understand many other ways that
you could have this overheat thing going on. I can only think of a few
other things that may have something to do with it:
* Clogging or similar fluid restriction that causes the fluid to not
flow through well enough at higher than idle speeds
* Opening in the system somewhere (radiator cap, hose, heater core,
heater hoses, throttle body cooling hoses, gaskets, etc. not holding the
pressure)
* Thermostat wasn't actually replaced (Jiffy Lube got busted for not
doing $99 transmission service jobs, for example)
* Thermostat is defective
* Thermostat wasn't installed properly when it was replaced
* Coolant temperature sensor defective
* Miscellaneous electrical problem
On a car that's 13 years old like that, I'd replace all the hoses and
easy-to-reach gaskets ANYWAY, especially if I wasn't sure what the last
guy did to it.