Thermostat stuck open

HIDDENFALLS

MEMBER
BUICK LESABRE

I have a 1987 Lesabre which I replaced a thermostat that was stuck open for quite a while (I assume) I only noticed it during the winter when I had no heat.

I got that replaced and voila good heat again, however I think it is stuck open again(after a week) because I only get a little amount of heat and running the engine for about 10 mins and it seems to get cooler as I drive.

My question is what can cause a thermostat to be stuck open, overheating of coolant?
I know I don't have a working radiator fan(electric) but it's during the winter and I rarely drive more than 5 miles to and from school. I suspect its a bad relay but I dont know where exactly it is.

1 Reply

TOBYU

MEMBER
89 POSTS

You can't overheat or hurt a new thermostat.
It could be a peice of crud therm but I doubt it.
It is probably low on coolant.
The first sign of low coolant in radiator is a poor heater. The second sign is car overheating.

If the cooling fan is not working. You should have even better heat. All the way to boiling over when you are stopped. When it is cold out. As long as you are moving forward in the air. It will not overheat as it has plenty of air going over the radiator.

THe relay is gouped with two or three more. Either on inside lip of either front fender. Or I really think they are near the firewall. Closer to pass side. Under blask plastic cover.I know a lot of Park Avenues did this.