1987 cooling issues
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From: Shindand AB
1987 cooling issues
Lately I have been noticing my cooling temp up over 220 highway driving and street driving. The oil temp would get over 230 also. When I got home I lifted the hood and did notice that the cooling fan was running.This morning, 70 degrees outside temp, I took the radiator cap off and started the engine. At 180 degrees, by the dash indicator, I did not see the cooling fluid circulate. As I would rev the engine via the throttle linkage, I could see the fluid level go down slightly. At 200 degrees, still no rapid circulation like should be seen if the thermostat had opened. Another observation, with the cap off is the hose running from the thermostat housing to the radiator was not under pressure, nor did it feel hot.
Could it be as simple as a thermostat( I mean that as far as cost, it sucks taking those two bolts off)? Or could it be the water pump? Both have been changed in the past couple of years, and the engine has been replaced, two years ago, about 20K miles. Radiator was replaced about 3 to 4 years ago.
While driving down the highway during this cool day, I would see the temp drop below 220.
Thanks for any suggestions.
Could it be as simple as a thermostat( I mean that as far as cost, it sucks taking those two bolts off)? Or could it be the water pump? Both have been changed in the past couple of years, and the engine has been replaced, two years ago, about 20K miles. Radiator was replaced about 3 to 4 years ago.
While driving down the highway during this cool day, I would see the temp drop below 220.
Thanks for any suggestions.
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From: Shindand AB
Thanks. I was hoping for only the thermostat. I guess if the water pump was not working it would be a lot worse. I am really getting tired of chaning these things. Anyone ever run with out one? I live in South Florida, so cold mornings are not an issue. I was just wondering if the seal is tight enough with just the gasket. I don't recall seeing the actual thermostat protuding to the outside edge of the housing.
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From: The Top of Utah
Originally Posted by beachcat
Thanks. I was hoping for only the thermostat. I guess if the water pump was not working it would be a lot worse.
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From: The Top of Utah
Originally Posted by beachcat
Thanks. I was hoping for only the thermostat. I guess if the water pump was not working it would be a lot worse.
BTW, there should be no pressure on the upper hose, or anywhere else in the cooling system, with the cap off.
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From: Shindand AB
So, with the cap on and the engine hot, over 180, should the upper hose be hard or not if the thermostat was not working but the pump was?
The area between the radiator and condeser is clear. These are some of the first things I check, as well as any paper up againest the radiator.
The area between the radiator and condeser is clear. These are some of the first things I check, as well as any paper up againest the radiator.
Team Owner
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From: Cincinnati, Oh USA
When you look into the open filler and the engine coolant is above the opening temp of the thermostat and no coolant is flowing into the top of the radiator, you have a thermostat that is not open. Replace your defective thermostat. And yes, the gasket is adequite to prevent the thermostat housing from leaking.
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From: The Top of Utah
Originally Posted by beachcat
So, with the cap on and the engine hot, over 180, should the upper hose be hard or not if the thermostat was not working but the pump was?
Originally Posted by beachcat
Another observation, with the cap off is the hose running from the thermostat housing to the radiator was not under pressure, nor did it feel hot.
Originally Posted by beachcat
I believe I will remove the thermostat, put in a new gasket and check it out. I really hate those bolts, but it could be worse.
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Melting Slicks
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From: The Black Hole LA
If you are seeing it not go over 220 then its not the t-stat stuck closed, it would shoot up way higher than that. I agree with CFI that changing the gasket will do you nothing. I also agree with CFI that 90% of the time when someone posts with this problem it is trash build-up between the ratiator and condensor. Take the top off the radiator shroud off and you should be able to look down in there and see.
On another note you said the water pump had been replaced, did you buy a remanufactered water pump? I went through 2 reman. pumps in 2 years before I got tired of changing them and spent the extra money and bought a brand new one. If it is the pump they can be on their way out but not out completely out and still circulate enough water to cool it some, but not what it should. I had this happen before on one of my remanufatured pumps mentioned above and as long as I kept water in it, it would cool enough to get it down the road (had to do this when it busted on a 3 hour drive, when I got to my destination, I went straight to the parts store and bought the brand new one). But I could see coolant leaking from the bottom of the pump.
On another note you said the water pump had been replaced, did you buy a remanufactered water pump? I went through 2 reman. pumps in 2 years before I got tired of changing them and spent the extra money and bought a brand new one. If it is the pump they can be on their way out but not out completely out and still circulate enough water to cool it some, but not what it should. I had this happen before on one of my remanufatured pumps mentioned above and as long as I kept water in it, it would cool enough to get it down the road (had to do this when it busted on a 3 hour drive, when I got to my destination, I went straight to the parts store and bought the brand new one). But I could see coolant leaking from the bottom of the pump.
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From: Shindand AB
Because I have had similar problems with the cooling system before, I know all about the trash that can get between the rad and cond., been checked. As for just changing the gasket, I stated that I would remove the current thermostat, put in a new gasket(because they usually get torn up on removal) then test the system. The engine was replaced two years ago, sorry for the confusion, but I have had that many things replaced on it over the years. Prior to the new engine being put in, a new water pump and thermostat was replaced.
No leaks on the ground, no over flows to the tank. Coolant level was at the top of the cap this morning right before starting it.
No leaks on the ground, no over flows to the tank. Coolant level was at the top of the cap this morning right before starting it.
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From: Shindand AB
yup, I thought of that also. Thanks.
Removed old thermo, put it and the new one in the boiling water to test.
Old one failed, new one passed and installed. I really hate those two bolts.
Thanks again for all of the suggestions.
Removed old thermo, put it and the new one in the boiling water to test.
Old one failed, new one passed and installed. I really hate those two bolts.
Thanks again for all of the suggestions.
Last edited by beachcat; Nov 23, 2005 at 08:12 PM.
Racer
Joined: Feb 2004
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From: Irwindale Ca
easy to test a thermostat.. make sure water is in system. a 180 thermostat with climb from cold consistently at idle until it reaches around 180..181 183.. then it will drop below 180. Keep idling it and you will see the 178 temp crawl back to 180 181 182.. then back to 180. This is the thermostat opening. After a few minutes the water in the radiator will heat up and the temps will begin to climb to 220 or when the fan turns on.
If there is a consistent climb to 220 without any drop, the thermostat is stuck closed... Simple common sense...
If there is a consistent climb to 220 without any drop, the thermostat is stuck closed... Simple common sense...
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From: Shindand AB
After testing the new 160 thermo in the boiling water, I decided to put it in with a new gasket anyway. I drove it some 40 miles on the highway yesterday, and drove at idle thru 3 miles of a parade that took almost an hour with no overheat issues. I just need to check the coolant level over the next few days.