I'm Overheating
Thread Starter
Burning Brakes
Joined: May 2006
Posts: 865
Likes: 53
I'm Overheating
All of a sudden , I've been overheating . I have a 71 w/ 350 . It overheats when I start , at idle . When I drive on PkWy , it cools down . Then stop and go , it overheats . It started a few weeks ago and has gotten worse . No leaks . Could it be fan clutch ?
Thread Starter
Burning Brakes
Joined: May 2006
Posts: 865
Likes: 53
I'm
Maybe . Thermostat - 180 - is new , pump is 3 years old , lower rad spring seems good , keeps roundness when I squeeze , I was thinking clutch fan because I can't seem to find much info or even where to buy ! Flushing sounds good to start . Thanks
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I would be looking at the clutch fan if it's running too hot when idling and runs cool when under way. When you say it is overheating is it actually boiling over? What reading are you getting on your gauge? Have you confirmed it's accuracy with an IR gun?
Good luck.
Good luck.
Drifting
Joined: Sep 2006
Posts: 1,259
Likes: 2
From: MS
The symptom of overheating in the city but cooling on the highway points to an air flow problem.
Sounds to me like a fan, clutch, shroud, seals, etc. issue. To test the clutch, get the engine up to
full temp then shut it down, the fan should stop almost immediately. Should also feel resistance
when turning by hand when engine is hot, if not clutch is gone and needs replacing.
Sounds to me like a fan, clutch, shroud, seals, etc. issue. To test the clutch, get the engine up to
full temp then shut it down, the fan should stop almost immediately. Should also feel resistance
when turning by hand when engine is hot, if not clutch is gone and needs replacing.
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Thread Starter
Burning Brakes
Joined: May 2006
Posts: 865
Likes: 53
I'm
No , it didn't boil over . I was on PkWy , heat OK. Then , stop and go , heat slowly pins guage . I turned it off , opened hood , everything looks good . I tried to start , and starter wouldn't turn . Waited 15 min , car cooled down , started up , temp started to rise but I made it to PkWy. Heat went down , went home . Theres water , pump looks fine , no leaks or anything . Tomorrow I'll start testing things mentioned here . Thanks all !
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Almost certasinly a fan clutch or shroud problem. Start there. Rad seals would allow air to bypass radiator at hiway speeds causing heat. The clue is Idle/slow speed. About the only thing that will do that is air flow or the lack of it from the engine driven fan.
Drifting
Joined: Apr 2006
Posts: 1,911
Likes: 2
From: gold coast queensland
Thread Starter
Burning Brakes
Joined: May 2006
Posts: 865
Likes: 53
I'm
Well , at first I thought of tstat , So I bought one , least expensive things first , right ? When I got home , pulled housing , no thermostat ! So I put the Slant 180 I bought in anyway , but it had been running OK for 3 years without it so thats not it . There , stopped that as a problem or issue . Well , theres a foot of snow in Malverne LI , so I'm just going to have a nice day inside . Thanks everyone . This forum is a great place but I do miss knowledge people like lars and durangoboy , but theres a lot others . Thanks again .
Melting Slicks
Joined: Oct 2004
Posts: 2,662
Likes: 8
From: Knoxville Tennessee
I have seen new t-stats be bad out of the box. You could have a vapor lock in the system. The front of the car needs to be up on ramps to force all the air in the system to the radiator cap where it can be expelled. Other than that, it sounds like a fan clutch problem to me.
Electric fans would cure that problem unless you just wanted to have the original fan on the car.
Bernie
Electric fans would cure that problem unless you just wanted to have the original fan on the car.
Bernie