Driver fan running properly now...still overheat...
#16
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Question:
About the air in the system, does it just appear there? It was never there before, that I know of, because it hasn't overheated since June (when the thermo was preplaced). Does the air just get in there?
Is it same to drive, today is cold.
-Matt
About the air in the system, does it just appear there? It was never there before, that I know of, because it hasn't overheated since June (when the thermo was preplaced). Does the air just get in there?
Is it same to drive, today is cold.
-Matt
#17
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Originally posted by Matt Olde:
<STRONG>...Is the temp sending unit the thermostat? ...</STRONG>
<STRONG>...Is the temp sending unit the thermostat? ...</STRONG>
Check the conections to the temp sensor to make sure you have a good contact. Check the date on the sensor to make sure you have a post 2/8 (Feb. 88) stamped on the switch/sensor housing. Most likely this will be the culprit.
The gauge can be broken but I really doubt that... replace the sending/sensor unit, again, bleed the system and check.
Good luck!
#18
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Matt, Just this morning while driving to work, I noticed my gauge at the second mark. The car NEVER runs that hot, and it was only 27 deg. this morning. As I pulled away from the light the needle immediatly fell to halfway between the first and second marks. I knew I had a LITTLE air in the system, as the last time I did it I only did the procedure 2 or 3 times, and could still hear the air in the heater core. When I got home an hour or so ago I noticed the fans weren't running, so I figured it was time to check it out. The #15 fuse was blown, but after replacing it the fan still didn't come on. The coolant level was just above the low mark, so I decided to top it off and finally bleed the system. A gallon later, the fans run, the needle acts as it should. and I can still hear just a hint of air in the heater core.
Bleeding it is easy, and it can't hurt so it's worth a shot. I can't tell you where it (the air) comes from, but it gets in there. My problem sounds just like yours, and after an hour with a 12mm wrench, mine is solved! HTH
Bleeding it is easy, and it can't hurt so it's worth a shot. I can't tell you where it (the air) comes from, but it gets in there. My problem sounds just like yours, and after an hour with a 12mm wrench, mine is solved! HTH
#19
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Please please please let it be that...
I took it for a spin down to the airport for my flight lesson, cool night, should be fine...
Well, everything is cool, but I just pulled in the garage and I hear a gurgling noise coming from the engine. On the way home it hovered around the first mark, only at stop lights got up past it.
The really crappy thing is my fans aren't on. I shut off the car, and the fans shut off as well. That is a FIRST. I repeat, that didn't happen until just now. What gives? Is there any docs on how to bleed the system?
Thanks,
Matt
PS
We ARE going to win this battle fellas!!
I took it for a spin down to the airport for my flight lesson, cool night, should be fine...
Well, everything is cool, but I just pulled in the garage and I hear a gurgling noise coming from the engine. On the way home it hovered around the first mark, only at stop lights got up past it.
The really crappy thing is my fans aren't on. I shut off the car, and the fans shut off as well. That is a FIRST. I repeat, that didn't happen until just now. What gives? Is there any docs on how to bleed the system?
Thanks,
Matt
PS
We ARE going to win this battle fellas!!
#20
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Oh boy...
I just went back down to take a look, and I found my coolant resevoir dead empty.
This is odd because when I came up here just a few minutes ago I looked at it and it was at MAX (when car is cool, it is smack in the middle). Where did all my coolant go? There is not a drop on the ground - did it up and walk out?
I cracked the cap on the coolant (with a large towel) and I heard a de-pressurized sound, but still no coolant.
Help?
-Matt
I just went back down to take a look, and I found my coolant resevoir dead empty.
This is odd because when I came up here just a few minutes ago I looked at it and it was at MAX (when car is cool, it is smack in the middle). Where did all my coolant go? There is not a drop on the ground - did it up and walk out?
I cracked the cap on the coolant (with a large towel) and I heard a de-pressurized sound, but still no coolant.
Help?
-Matt
#22
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Haynes manual, pages 47-48.
In short; "Remove bleed plug," on my '86 it's on the top of the head, on the elbow where American cars put the thermostat(the upper radiator hose is attached to it). It's a 12mm bolt head. "SLOWLY fill the cooling system until the reservoir level is at the max mark. (I waited until I saw coolant at the bleed plug hole) Run the engine until normal operating temp is reached,(the fan has turned on and off) and the coolant issueing from the bleed plug no longer has any air bubbles. Tighten plug securely, add coolant as needed to bring the reservoir level to between the max and min marks."
I've found that some air will still be in the system, and to crack the plug loose a few times (a few days apart) when the engine is warm, to let the air that has risen to this point escape. Also make sure the heater valve is open so the heater core is filled as well. Check the coolant level andadd more if needed.
In short; "Remove bleed plug," on my '86 it's on the top of the head, on the elbow where American cars put the thermostat(the upper radiator hose is attached to it). It's a 12mm bolt head. "SLOWLY fill the cooling system until the reservoir level is at the max mark. (I waited until I saw coolant at the bleed plug hole) Run the engine until normal operating temp is reached,(the fan has turned on and off) and the coolant issueing from the bleed plug no longer has any air bubbles. Tighten plug securely, add coolant as needed to bring the reservoir level to between the max and min marks."
I've found that some air will still be in the system, and to crack the plug loose a few times (a few days apart) when the engine is warm, to let the air that has risen to this point escape. Also make sure the heater valve is open so the heater core is filled as well. Check the coolant level andadd more if needed.
#23
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Anytime someone replaces something like a thermostat or even a fan switch, anywhere from some to a lot of coolant gets out of the system. So this is how air gets in. Also, if you let the level in the reservoir get too low, it'll let air in.
The fact that a bunch of coolant disappeared and didn't leak out is probably good. This means your cooling system jostled loose some air and circulated it into the reservoir. Air enters the reservoir, but coolant leaves it into the system. Ergo the level drops. Mine did this too after all the messing around with bleeding it. It'll probably do it a couple more times (the level will drop) so keep an eye on it.
I think you'll be fine once you get the system truly air-free.
Bryan
The fact that a bunch of coolant disappeared and didn't leak out is probably good. This means your cooling system jostled loose some air and circulated it into the reservoir. Air enters the reservoir, but coolant leaves it into the system. Ergo the level drops. Mine did this too after all the messing around with bleeding it. It'll probably do it a couple more times (the level will drop) so keep an eye on it.
I think you'll be fine once you get the system truly air-free.
Bryan