Topic: Radiator Cap
in Forum: C3 Cooling and Heating Systems
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Howdy!
For the last year or so I have had five different water necks (thermostat housings) fail. I have used the O-Ring type gaskets when called for and the paper type gaskets when called for. Recently I used the blue colored silicone sealer under a scuffed up O-Ring type water neck without success. The stock type water necks with the silicone failed too.
What normally happens is after the motor cools down overnight I find a puddle of antifreeze on the (Edelbrock Performer) intake manifold.
Thanks for any suggestions.
Kevin
Question is;
Would a radiator cap with a lower pressure solve this problem?
Any bad side effects from using a radiator cap with lower pressure?
This is driving me NUTZ!!!
Thanks for any suggestions.
Kevin
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Are the mounting surfaces of the housing and the intake square??? Place a straight edge on top of the mounting area on the intake and see if it is flat. Check the the t-housing too. If you have a high or low spot then that is where the leak is. I would look at the hose also.
I know I know, I have problems drwaing stick people too.
Hey Indy,
Yeah, I have checked the intake manifold with a metal straight edge and found it to be without any irregularities. The housings too. I've also made sure that both surfaces are clean and dry before getting to work.
I replaced the radiator hoses two years ago as preventative maintanance and recently I went with a 180 degree t-stat. The car has always run without overheating issues.
I just dunno!
I'm thinking the lighter pressure radiator cap might be worth trying. I'll wait for some more feedback.
Thanks for your reply.
Kevin
I have a similar issue with the Edelbrock, so I would also be interested in a solution.
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I am going to ask a dumb question. Are you sure the leak is from the T houshing. If I remember right one of the bolts that hold down the intake manifold up front goes into the head water jacket.
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have you actually seen coolant leak from the housing?
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kevin, i had a stat cover with the o ring type gasket. started it up one time and was leaking. i took it off and checked everything and it appeared ok. what i found when i was reinstalling it was that the bolts i was using were just a hair too long and i installed a washer on both bolts and it solved the problem. don't know why i didn't notice it when i first put the housing on or why it didn't leak for a while but just figured i was lucky. hope this might help.
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Going to a lower pressure rad cap is not a good idea...it's gonna spit coolant out before it gets to normal operating temp, plus, the higher the pressure in the system, the higher the boiling point of the coolant is.
I've run into situations similar to yours, and I've found that the leak will stop itself eventually. This is assuming that the leak is actually coming from between the neck and the intake....
I wouldn't recommend using any type of sealant on the gasket, neck, or intake...just clean & dry.
I've run into situations similar to yours, and I've found that the leak will stop itself eventually. This is assuming that the leak is actually coming from between the neck and the intake....
I wouldn't recommend using any type of sealant on the gasket, neck, or intake...just clean & dry.
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I'm pretty darn sure it's coming from the t-stat housing. Reason is that I can see a stain where the green antifreeze runs out from just under the housing on to the manifold.
As far as the bolts go, I used washers on the last one without success.
Any input as to the lower pressure radiator cap?
Lem'me know.
Hey Joel,
Looks like we were typing at the same time.
I picked up another housing today. This one's polished aluminum with an O-Ring. The guy at the speed shop has had some good advice in the past and he says he hasn't had any complaints with this one.
Your info on the radiator cap makes good sense. I'll stay with the original cap.
Wish me luck. 
in Forum: C3 Cooling and Heating Systems
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