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Valentine One Radar Detector

eesquared
04-04-2011, 09:53 PM
Ok, we put in the new radiator, burped it, added more coolant, ran it around the block, added more coolant, burped it, ran it around the block again, burped it again.

The top radiator hose is not pressuring up. We even put new clamps on. No leaks anywhere.

While driving around the block the second time, I turned on the heater full blast and left it that way until I got back home. The top radiator hose was squishy - not firm. Hubby said that after the car was turned off, that the coolant in the reservoir might drain into that hose and pressure it up. Didn't happen.

So, his diagnosis is that the thermostat is malfunctioning, or defective, or installed incorrectly....or something.

And no, we did not think to check the thermostat when we had the hose off. Why would I think that? They just put a new one on.

I have to go back to the shop and get them to check it.
grrrrr.....:confused:

dom
04-04-2011, 10:04 PM
Maybe you have a low pressure radiator cap on it?

Was the top hose hot like the bottom hose?

If the top hose is hot, you have flow.

If both hoses are hot and the unit is not losing coolant or overheating I say just drive it!

When I am topping off my coolant I bring the engine up to operating temperature (with the thermostat cycling), grab the throttle side of the carb/throttle body and give the unit a high steady rev and the coolant level drops. I then top off the coolant while maintaining the high rev (maybe 2,000 rpms) and put the radiator cap back on while holding the rev. After the cap is back on I left off the throttle.

Eric
04-05-2011, 06:39 AM
Why take it to the shop?

Changing out the thermostat on this car is extremely easy, Erin. You can do it!

With the engine cold:

Loosen/remove the radiator cap to relieve any pressure in the system.

Follow the top hose to the end that goes to the intake manifold. The housing the hose clamps onto is where the T-stat is. It is held in place by two 1/2 or 9/16 bolts.

Loosen the hose clamp and pull off the hose. (To limit spillage, I'd unclamp the hose at the radiator end first, then use a catch pan to collect the coolant. Also put some absorbent rags on the intake manifold, around the T-stat housing.)

Now use a socket wrench to loosen/remove the bolts and pry off the little metal housing. It may be sticky.

The T-Stat is now exposed; remove the old one.

Scrape off any gunk/old gasket material. Install the new T-stat. If it didn't come with a gasket, you'll need some blue RTV to run a bead around the perimeter of the housing to prevent leaks. Even if you got a gasket, I'd still run a little RTV on top because over the years the parts have probably eroded/warped a little and this will prevent seepage/leaks

Install the housing and tighten down - not too tight or you will crush the gasket and it'll leak.

Reinstall the hose, tighten and top off the radiator.

Done!

The whole job should not take you more than 15 minutes.

grouch
04-05-2011, 08:59 AM
Ok, we put in the new radiator, burped it, added more coolant, ran it around the block, added more coolant, burped it, ran it around the block again, burped it again.

The top radiator hose is not pressuring up. We even put new clamps on. No leaks anywhere.

While driving around the block the second time, I turned on the heater full blast and left it that way until I got back home. The top radiator hose was squishy - not firm. Hubby said that after the car was turned off, that the coolant in the reservoir might drain into that hose and pressure it up. Didn't happen.

So, his diagnosis is that the thermostat is malfunctioning, or defective, or installed incorrectly....or something.

And no, we did not think to check the thermostat when we had the hose off. Why would I think that? They just put a new one on.

I have to go back to the shop and get them to check it.
grrrrr.....:confused:



I think you have a minor problem that is being overlooked. Is the thermostat the right one? I've seen them give you the wrong unit and it will either overheat or not warm up at all. I've also seen them air lock. If the thermostat doesn't have a jiggle valve (that's really it's name) to let air bleed through, I usually will drill a 1/64 hole in the housing to let air bleed through. Air will get through but coolant is thicker and won't flow enough to matter.

Is the radiator cap good? You can check it with a pressure tester they have at AutoZone and other stores. I usually just replace them, it's cheap and easy to do with the engine cool.

What kind of history does the engine have? When was the timing chain replaced last? Who did it? Did they degree it or is it a bone stock type part? If the timing is off, the engine will run hot nearly every time. The same with the distributor timing. What is it set at with, and without, the vacuum advance?

eesquared
04-05-2011, 08:28 PM
Maybe you have a low pressure radiator cap on it?

Was the top hose hot like the bottom hose?

If the top hose is hot, you have flow.

If both hoses are hot and the unit is not losing coolant or overheating I say just drive it!

When I am topping off my coolant I bring the engine up to operating temperature (with the thermostat cycling), grab the throttle side of the carb/throttle body and give the unit a high steady rev and the coolant level drops. I then top off the coolant while maintaining the high rev (maybe 2,000 rpms) and put the radiator cap back on while holding the rev. After the cap is back on I left off the throttle.
Since there is no brand name on the radiator cap, I do not know if it is a low pressure one or not. I know that it is hard to get off sometimes. It looks fairly new - meaning all the writing and stuff is still legible and clean. It has little arrows on it that point to 'line up with vent tube'. I have to push down and turn 1/4 turn, then push down harder and turn another 1/4 turn, then it will come off. I have to press pretty hard, so I think it has pretty good seal. The radiator cap does not have one of those little red levers on it that releases pressure.

Yes, the top hose was hot....just squishy.

I cannot tell the rpms. I have idiot lights. But, I have to get it running before I'm going to swap the lights for gauges.

eesquared
04-05-2011, 08:34 PM
Why take it to the shop?

Changing out the thermostat on this car is extremely easy, Erin. You can do it!

With the engine cold:

Loosen/remove the radiator cap to relieve any pressure in the system.

Follow the top hose to the end that goes to the intake manifold. The housing the hose clamps onto is where the T-stat is. It is held in place by two 1/2 or 9/16 bolts.

Loosen the hose clamp and pull off the hose. (To limit spillage, I'd unclamp the hose at the radiator end first, then use a catch pan to collect the coolant. Also put some absorbent rags on the intake manifold, around the T-stat housing.)

Now use a socket wrench to loosen/remove the bolts and pry off the little metal housing. It may be sticky.

The T-Stat is now exposed; remove the old one.

Scrape off any gunk/old gasket material. Install the new T-stat. If it didn't come with a gasket, you'll need some blue RTV to run a bead around the perimeter of the housing to prevent leaks. Even if you got a gasket, I'd still run a little RTV on top because over the years the parts have probably eroded/warped a little and this will prevent seepage/leaks

Install the housing and tighten down - not too tight or you will crush the gasket and it'll leak.

Reinstall the hose, tighten and top off the radiator.

Done!

The whole job should not take you more than 15 minutes.
Yes, I know where the thermostat is located. It sounds really easy to do, and I know that gear-head-guys can do it rather quickly. It might take me a little longer....

Hubby suggested that I pressure test the system. I'm calling the parts store to see if they might do it for me, or if I need to 'rent' the tester.

And, I will pick up a new fail-safe thermostat while I am there....just in case.

Thanks for the step-by-step instructions!

eesquared
04-05-2011, 08:42 PM
I think you have a minor problem that is being overlooked. Is the thermostat the right one? I've seen them give you the wrong unit and it will either overheat or not warm up at all. I've also seen them air lock. If the thermostat doesn't have a jiggle valve (that's really it's name) to let air bleed through, I usually will drill a 1/64 hole in the housing to let air bleed through. Air will get through but coolant is thicker and won't flow enough to matter.

Is the radiator cap good? You can check it with a pressure tester they have at AutoZone and other stores. I usually just replace them, it's cheap and easy to do with the engine cool.

What kind of history does the engine have? When was the timing chain replaced last? Who did it? Did they degree it or is it a bone stock type part? If the timing is off, the engine will run hot nearly every time. The same with the distributor timing. What is it set at with, and without, the vacuum advance?
Funny you should mention the pressure tester. I am going to see if I can check one out this evening.

The thermostat is a Murray 195 degree thermostat. But, i do not think it is a fail-safe one. That is what I plan to get and replace it.

Yes, the radiator cap is in good condition - it looks to be fairly new. The labels are all clearly legible and clean; the chrome stuff is still very shiny; it seals well and is kind of hard to turn (for me) to get it off.

I did notice when we were looking at the car (looking dumbfounded, can we say <duh>??) that it does need new plugs. One of the plugs looks a tiny bit rusty, so I do need to tune it up.

I have no idea about the timing chain or the distributor timing. We have not done that since I bought the car, so that is on the list of to-dos.

grouch
04-05-2011, 10:27 PM
Funny you should mention the pressure tester. I am going to see if I can check one out this evening.

The thermostat is a Murray 195 degree thermostat. But, i do not think it is a fail-safe one. That is what I plan to get and replace it.

Yes, the radiator cap is in good condition - it looks to be fairly new. The labels are all clearly legible and clean; the chrome stuff is still very shiny; it seals well and is kind of hard to turn (for me) to get it off.

I did notice when we were looking at the car (looking dumbfounded, can we say <duh>??) that it does need new plugs. One of the plugs looks a tiny bit rusty, so I do need to tune it up.

I have no idea about the timing chain or the distributor timing. We have not done that since I bought the car, so that is on the list of to-dos.



I put two failsafes in my Taurus and they both failed. I thought the third (non-failsafe) thermostat failed but it was a wire problem then.

If the pressure tester doesn't show any problems, I'd check the timing chainfor slop and also check the ignition timing.

How many miles on this engine? It sure sounds like either your timing is off (you need a timing light to check) or you have an exhaust problem from either stoppage or a crossover problem. (A vacuum gauge will show that.)

Eric
04-06-2011, 06:09 AM
I promise it's easy!

You will need a basic socket set and some screwdrivers.

Be sure the engine is cold before you start. Coolant can burn you.

Be sure you open the radiator cap first, to relieve the pressure.

Once the job is done, top off the radiator, but leave the cap off. Now start the engine and let it warm up. When the T-stat opens, the coolant level in the radiator should drop a little as fluid is sucked through the system. Add more. Raise/blip the throttle a little - this should "burp" any bubbles within the system. Some coolant may spill out of the top of the radiator as you do this. It's normal. Top off again, as necessary (with the engine still running). Now install/close the radiator cap.

This ought to do it!

Eric
04-06-2011, 06:13 AM
"It sure sounds like either your timing is off (you need a timing light to check) or you have an exhaust problem from either stoppage or a crossover problem. (A vacuum gauge will show that.)"

IIRC her Chevy has that clunky EFE heat riser deal on the passenger side exhaust manifold. It's vacuum controlled, but the actual flapper mechanism sometimes freezes up.

Elky, how many miles on the clock?

grouch
04-06-2011, 08:20 AM
"It sure sounds like either your timing is off (you need a timing light to check) or you have an exhaust problem from either stoppage or a crossover problem. (A vacuum gauge will show that.)"

IIRC her Chevy has that clunky EFE heat riser deal on the passenger side exhaust manifold. It's vacuum controlled, but the actual flapper mechanism sometimes freezes up.

Elky, how many miles on the clock?


She was talking about putting headers on it. They wouldn't have the diverter valve (flaper).

dom
04-06-2011, 08:59 AM
What year was this El again? What engine?

eesquared
04-06-2011, 01:15 PM
I put two failsafes in my Taurus and they both failed. I thought the third (non-failsafe) thermostat failed but it was a wire problem then.

If the pressure tester doesn't show any problems, I'd check the timing chainfor slop and also check the ignition timing.

How many miles on this engine? It sure sounds like either your timing is off (you need a timing light to check) or you have an exhaust problem from either stoppage or a crossover problem. (A vacuum gauge will show that.)
49,000 original miles.

eesquared
04-06-2011, 01:25 PM
I promise it's easy!

You will need a basic socket set and some screwdrivers.

Be sure the engine is cold before you start. Coolant can burn you.

Be sure you open the radiator cap first, to relieve the pressure.

Once the job is done, top off the radiator, but leave the cap off. Now start the engine and let it warm up. When the T-stat opens, the coolant level in the radiator should drop a little as fluid is sucked through the system. Add more. Raise/blip the throttle a little - this should "burp" any bubbles within the system. Some coolant may spill out of the top of the radiator as you do this. It's normal. Top off again, as necessary (with the engine still running). Now install/close the radiator cap.

This ought to do it!
hee hee....If I cannot find a screwdriver and sockets in my husband's garage, then I am a total moron. There are only about fifteen thousand tool chests and tool boxes in there...Hubby left the ones I need for my car are handily placed where I need them.

eesquared
04-06-2011, 01:26 PM
"It sure sounds like either your timing is off (you need a timing light to check) or you have an exhaust problem from either stoppage or a crossover problem. (A vacuum gauge will show that.)"

IIRC her Chevy has that clunky EFE heat riser deal on the passenger side exhaust manifold. It's vacuum controlled, but the actual flapper mechanism sometimes freezes up.

Elky, how many miles on the clock?
Yeah - what Eric said. I had headers put on.

49,000 miles on the car.

eesquared
04-06-2011, 01:27 PM
What year was this El again? What engine?
1986, small block 305.

dom
04-06-2011, 08:11 PM
1986, small block 305.

Nice. Every time I see your avatar it makes me wanna take mine out for a spin.

eesquared
04-07-2011, 08:37 AM
Nice. Every time I see your avatar it makes me wanna take mine out for a spin.
Thanks - only it's not being very nice right now.

dom
04-08-2011, 10:43 PM
Sure it's being nice. If it ain't over heating, just drive it!

eesquared
04-09-2011, 10:35 AM
Thanks all for your excellent mechanical skills and advice!

We pressure tested the cap and believe that was the culprit. So, we replaced it with one that has a red pressure-reliever thingie on it. The hose pressured up! So, we did not have to replace the thermostat. I drove it around town for a while running errands, and the temp light never came on.

Yeaahhhh!! Now, we can get around to the timing and other stuff.