Overheating
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From: Albany NY
Overheating
1984
I have had sporadic overheating but nothing constant, until now. Coolant bubbles/boils out the radiator (without cap on). I can hear it bubling with cap on. Was going to try one of those "head gasket" miracle cures, but, nah that will not work.
Does this sound like a head gasket? I have done some work before on cars, not too much on this one. Did a head gasket on my sons 2005 Accord (4 cylinder) took some time but managed through it.
Is this something a novice can handle? I assume this would be over $1000 if I had it done by a mechanic.
I should add. There is oil in coolant, no coolant in oil.
I have had sporadic overheating but nothing constant, until now. Coolant bubbles/boils out the radiator (without cap on). I can hear it bubling with cap on. Was going to try one of those "head gasket" miracle cures, but, nah that will not work.
Does this sound like a head gasket? I have done some work before on cars, not too much on this one. Did a head gasket on my sons 2005 Accord (4 cylinder) took some time but managed through it.
Is this something a novice can handle? I assume this would be over $1000 if I had it done by a mechanic.
I should add. There is oil in coolant, no coolant in oil.
Last edited by pbennison; Oct 22, 2019 at 02:00 PM. Reason: update
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From: Albany NY
Quick update.
I checked compression on right side, all around 90PSI. Only did #2 on left so far, also 90PSI.
One question - Oil looks perfect, as good as when I changed it in spring. Would it be possible that it could be the water pump? Just thinking logically, taking away the fact that oil got in the coolant. Car overheated sporadically before this, I could see temp climb then all of a sudden it would be normal. Knowing the coolant flows from bottom to top and that when I pulled and replaced thermostat, it looked as though it was not getting coolant up there. Also, thermostat tested fine.
Maybe I am hoping against hope here, but was thinking of trying to replace water pump (I can do that). Guess I would be risking $75-100 and my time. Don't care about my time and the $75-100 seems like a worthwhile risk.
Thoughts on that?
I checked compression on right side, all around 90PSI. Only did #2 on left so far, also 90PSI.
One question - Oil looks perfect, as good as when I changed it in spring. Would it be possible that it could be the water pump? Just thinking logically, taking away the fact that oil got in the coolant. Car overheated sporadically before this, I could see temp climb then all of a sudden it would be normal. Knowing the coolant flows from bottom to top and that when I pulled and replaced thermostat, it looked as though it was not getting coolant up there. Also, thermostat tested fine.
Maybe I am hoping against hope here, but was thinking of trying to replace water pump (I can do that). Guess I would be risking $75-100 and my time. Don't care about my time and the $75-100 seems like a worthwhile risk.
Thoughts on that?
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From: Glenbeulah Wi
I would do some more checking on why it is overheating. I would assume you are loosing coolant, and that is causing your overheating problem. Getting oil in the coolant but no coolant in the oil does not seem very likely. I doubt you have a blown head gasket.
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From: Albany NY
Thanks for the reply, I am hoping it is not a head gasket so that makes me feel better.
Once I started getting sporadic overheating I checked coolant level more frequently. And actually the other day, I was running the car with rad cap off and it would bubble/boil right out the top of the radiator. That is what made me think water pump.
Once I started getting sporadic overheating I checked coolant level more frequently. And actually the other day, I was running the car with rad cap off and it would bubble/boil right out the top of the radiator. That is what made me think water pump.
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From: Park City Utah
What could go wrong with the water pump?
1. the bearing/seal go out, coolant leaks out. Is that happening
2. The impeller rusts away and/or detaches from the shaft, so doesn't pump water. Is that likely? It's incredibly unlikely.
Does the engine make heat for the heater? Does the radiator get warm when the T-stat opens? If so, the water pump is pumping water.
1. the bearing/seal go out, coolant leaks out. Is that happening
2. The impeller rusts away and/or detaches from the shaft, so doesn't pump water. Is that likely? It's incredibly unlikely.
Does the engine make heat for the heater? Does the radiator get warm when the T-stat opens? If so, the water pump is pumping water.
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From: Albany NY
Thanks everyone. Luckily it is almost winter here. Since the oil looked perfect (no water) i was thinking/hoping not a blown head gasket. Is it possible to have a blown head gasket where oil ONLY leaks into coolant? My initial thoughts were the usual suspects when overheating, thermostat (replaced and checked), water pump which I was thinking would be a relatively cheap (money not time) test. Other things I assume could be blocked heater core, although I do get heat once warmed up.
I guess I could take out thermostat, disconnect the upper radiator hose and see if there is flow?
I guess I could take out thermostat, disconnect the upper radiator hose and see if there is flow?
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From: Glenbeulah Wi
Thanks everyone. Luckily it is almost winter here. Since the oil looked perfect (no water) i was thinking/hoping not a blown head gasket. Is it possible to have a blown head gasket where oil ONLY leaks into coolant? My initial thoughts were the usual suspects when overheating, thermostat (replaced and checked), water pump which I was thinking would be a relatively cheap (money not time) test. Other things I assume could be blocked heater core, although I do get heat once warmed up.
I guess I could take out thermostat, disconnect the upper radiator hose and see if there is flow?
I guess I could take out thermostat, disconnect the upper radiator hose and see if there is flow?
Sounds to me like you are low on coolant which allows air in the sytem and the low volume causes the coolant not to flow or flow haphazardly. The wildly swinging temo gauge and heat no heat at the heater suggest low water level. Fill the coolant wit the engine running, car cool, to the top of the radiator and then fill the surge tank. Drive car see how it works.
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From: Albany NY
Thanks for this and I will do that this morning. Sorry, I am kind of thick on this stuff. My inclination is always try and fix it with a new part, I need to have some patience and figure out what is wrong.
I am confused about one thing. Yesterday, I drained the radiator, filled with water and then started and drove for about 10 minutes. When I got back home I let it cool down enough to SLOWLY release pressure from radiator cap and started engine again with cap off. Within a few minutes the water was bubbling/boiling out the radiator.
I am confused about one thing. Yesterday, I drained the radiator, filled with water and then started and drove for about 10 minutes. When I got back home I let it cool down enough to SLOWLY release pressure from radiator cap and started engine again with cap off. Within a few minutes the water was bubbling/boiling out the radiator.
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From: Glenbeulah Wi
Thanks for this and I will do that this morning. Sorry, I am kind of thick on this stuff. My inclination is always try and fix it with a new part, I need to have some patience and figure out what is wrong.
I am confused about one thing. Yesterday, I drained the radiator, filled with water and then started and drove for about 10 minutes. When I got back home I let it cool down enough to SLOWLY release pressure from radiator cap and started engine again with cap off. Within a few minutes the water was bubbling/boiling out the radiator.
I am confused about one thing. Yesterday, I drained the radiator, filled with water and then started and drove for about 10 minutes. When I got back home I let it cool down enough to SLOWLY release pressure from radiator cap and started engine again with cap off. Within a few minutes the water was bubbling/boiling out the radiator.
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From: Park City Utah
1. Where water and oil interface (you get foamy oil and black oil droplets in the coolant)
2. Where combustion gas and water interface (you get bubbles, pressure, and hydrocarbons in the coolant, & washed cylinders)
3. Out the side of the engine; either water and/or combustion. See coolant running down the block from the head flange, or soot at the head flange (mostly seen on an air cooled engine)
SO "the oil looks perfect", while good doesn't meant the head gasket isn't blown.
1. the heater core isn't clogged
2. your water pump is pumping water. If it weren't pumping water how would the heater core provide heat?
Highly unlikely
Sounds to me like you are low on coolant which allows air in the sytem and the low volume causes the coolant not to flow or flow haphazardly. The wildly swinging temo gauge and heat no heat at the heater suggest low water level. Fill the coolant wit the engine running, car cool, to the top of the radiator and then fill the surge tank. Drive car see how it works.
Sounds to me like you are low on coolant which allows air in the sytem and the low volume causes the coolant not to flow or flow haphazardly. The wildly swinging temo gauge and heat no heat at the heater suggest low water level. Fill the coolant wit the engine running, car cool, to the top of the radiator and then fill the surge tank. Drive car see how it works.
Totally. Do this first, then proceed.
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From: Mission Viejo CA
pbennison, before this became a major problem, were you having to add coolant to the radiator regularly? The radiator should stay 100% full, and there should be no coolant loss from the overflow reservoir. Do not remove the radiator cap unless the engine is cool.
(bjankuski and Tom: . . . just a reminder , , , the '84 has '624 heads.)
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Actually, there is an expansion tank.Not sure if the PO put it on there or not. It originally had the Evans waterless coolant in there but I switched back a few years ago.
Yes, I would occasionally have to add coolant. Not a lot, though, maybe half a gallon over the summer. I do know that during the hot, real hot days it tended to almost overheat.
This is where I am at. I went out this morning and filled the coolant with the engine running, car cool, to the top of the radiator and then fill the surge tank (post #10). I started it up and drove around. Everything was good until I got into some stop and go traffic and it climbed to about 210, once I was back on the open road it dropped to 190. Surge tank was low so I added coolant and took another drive, same thing it was great on the open road, but when I slowed down it would start creeping up. When I got back surge tank needed some but not a lot of coolant.
Is this an iterative process in that I should take some short drives and keep adding coolant? I do not see any active leaks.
Yes, I would occasionally have to add coolant. Not a lot, though, maybe half a gallon over the summer. I do know that during the hot, real hot days it tended to almost overheat.
This is where I am at. I went out this morning and filled the coolant with the engine running, car cool, to the top of the radiator and then fill the surge tank (post #10). I started it up and drove around. Everything was good until I got into some stop and go traffic and it climbed to about 210, once I was back on the open road it dropped to 190. Surge tank was low so I added coolant and took another drive, same thing it was great on the open road, but when I slowed down it would start creeping up. When I got back surge tank needed some but not a lot of coolant.
Is this an iterative process in that I should take some short drives and keep adding coolant? I do not see any active leaks.
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Joined: Sep 2001
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From: Glenbeulah Wi
Actually, there is an expansion tank.Not sure if the PO put it on there or not. It originally had the Evans waterless coolant in there but I switched back a few years ago.
Yes, I would occasionally have to add coolant. Not a lot, though, maybe half a gallon over the summer. I do know that during the hot, real hot days it tended to almost overheat.
This is where I am at. I went out this morning and filled the coolant with the engine running, car cool, to the top of the radiator and then fill the surge tank (post #10). I started it up and drove around. Everything was good until I got into some stop and go traffic and it climbed to about 210, once I was back on the open road it dropped to 190. Surge tank was low so I added coolant and took another drive, same thing it was great on the open road, but when I slowed down it would start creeping up. When I got back surge tank needed some but not a lot of coolant.
Is this an iterative process in that I should take some short drives and keep adding coolant? I do not see any active leaks.
Yes, I would occasionally have to add coolant. Not a lot, though, maybe half a gallon over the summer. I do know that during the hot, real hot days it tended to almost overheat.
This is where I am at. I went out this morning and filled the coolant with the engine running, car cool, to the top of the radiator and then fill the surge tank (post #10). I started it up and drove around. Everything was good until I got into some stop and go traffic and it climbed to about 210, once I was back on the open road it dropped to 190. Surge tank was low so I added coolant and took another drive, same thing it was great on the open road, but when I slowed down it would start creeping up. When I got back surge tank needed some but not a lot of coolant.
Is this an iterative process in that I should take some short drives and keep adding coolant? I do not see any active leaks.
Remember your cooling fans do not even come on until 228 degrees so the car getting up to 210 degrees in traffic is normal and it is still normal at 230 degrees.
Last edited by bjankuski; Oct 24, 2019 at 02:14 PM.
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Getting all the air out of the radiator is a PITA on our cars, due to layout. Some advice:
OP, have to ask, what are you considering overheating, how hot?
- When changing thermostat, drill a small hole in its middle piece (the flap that blocks coolant). This will let a little air out while the engine is still heating up.
- DO NOT EVER REMOVE THE RADIATOR CAP with car already running. I was a dumbass who thought air in the radiator when hot would allow a fill up. And burnt the **** out of myself. SAME GOES FOR A WARM ENGINE. Be safe, wait until stone cold.
- Having the front end up a bit more than the rear can help get the air out as well.
OP, have to ask, what are you considering overheating, how hot?
Last edited by kael; Oct 24, 2019 at 02:48 PM.
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From: Albany NY
Getting all the air out of the radiator is a PITA on our cars, due to layout. Some advice:
OP, have to ask, what are you considering overheating, how hot?
- When changing thermostat, drill a small hole in its middle piece (the flap that blocks coolant). This will let a little air out while the engine is still heating up.
- DO NOT EVER REMOVE THE RADIATOR CAP with car already running. I was a dumbass who thought air in the radiator when hot would allow a fill up. And burnt the **** out of myself. SAME GOES FOR A WARM ENGINE. Be safe, wait until stone cold.
- Having the front end up a bit more than the rear can help get the air out as well.
OP, have to ask, what are you considering overheating, how hot?
Overall, It seems I know just enough to be dangerous. I am so lucky to be able to use these forums. Hope someday I can pay back a little.
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From: Park City Utah
Everything was good until I got into some stop and go traffic and it climbed to about 210, once I was back on the open road it dropped to 190. Surge tank was low so I added coolant and took another drive, same thing it was great on the open road, but when I slowed down it would start creeping up.
When I fill coolant up in cars, I'll fill the radiator to the top when cold, just like you did, then I'll over fill the overflow bottle, knowing that there will be air that is expelled into the overflow bottle as the car runs and warms, and the system will draw some or most of the overage back into the cooling loop as it cools. I'll run it a day or two, then re-check the overflow bottle, top as necessary. Should stay there from then on.