sigh... heat problem in 95 sw1

Shortly aftter I bought my 95 SW1 in October of 2002, I noticed that the
temp gauge only went about 1/4 of the way up. I replaced the thermostat
with one from the dealer and the gauge stayed at 1/2. It has always taken
a bit of time to get there, but it got and stayed there. It also takes a
good 10 to 15 minutes to get heat up, but when it comes up, it is good and
hot.

Other people have told me that their Saturns warm up very quickly!

When it started getting cold here, the temp gauge again started only going
1/8 to 1/4 of the way up. On the highway it will almost get to 1/2. Ok, I
figured, the thermostat has failed.

Bought a new thermostat at NAPA this time, drained system this AM. Tested
the thermostat which was installed, it seemed fine. I did notice that the
thermostat housing has a weep hole in it.

http://teichholtz.home.mindspring.com/images/thermostat.jpg

The picture is a bit fuzzy, but one can see that the hole is about 1/8 inch
diameter. When I fill the inlet with water, the water obviously pours out
through the weep hole. One can blow through the inlet and the air comes
through the weep hole with very little resistance, although there is some.

Question: Is the weep hole supposed to be there? I don't think I have seen
such a thing in any other car.

I put the new thermostat in the housing, verified it's operation, and
installed it. Started the car and after about 15 minute of running the
gauge barely moved. The coolant in the resovoir is tepid to the touch.

My next step is to go to the parts department of the dealer and see if they
have a housing in stock that I can look at. If the weep hole is supposed to
be there I am going to drain the system, disconnect the hoses from the
radiator, plug them, refill the system,and run the car without a radiator in
the equation to see how long it takes to warm up. If it

 

Yes, the weep hole is supposed to be there. Or one in the
thermostat itself. There needs to be a little flow through there or
the thermostat will never get warm. However, that hole does look a
bit large -- the ones I've seen before are maybe 1/16" in diameter.
I suppose there could have been some sort of metal insert in there
that popped loose, or perhaps there's supposed to be a flange on the
thermostat that covers most of the hole (with a smaller weep hole in
the flange).

 

Yeah, come to think of it, My jeep thermostat has a tiny hole in the flange
with a little stick with crushed ends poked through it. I bet there is
supposed to be something like that on the Saturn housing. If you look
closely at the picture you can see that there is a machined depressed
rectangle around the hole. I wonder if that held something to stem the
flow.

-David