[cjheidt]

My TA is overheating. I have a 305HO engine with air conditioning, stock electric fan, newly rebuilt motor with comp cam and edelbrock carb (removed the ram air cap on top of the carb because it didnt fit).
I have tried several different things but still no luck.
I have replaced my air dam, Bipassed the relay for my electric fan (it now runs when the engine is on),removed my air conditioning rad, bought a new rad, changed my thermostat then totally removed it (which helped a little).
Some people say to replace the single fan with a double and others say to upgrade my rad.
I live in cold Canada so would like to run the fan thru the relay to keep warm when necessary.
Any suggestions?

[cjheidt]

My TA is overheating. I have a 305HO engine with air conditioning, stock electric fan, newly rebuilt motor with comp cam and edelbrock carb (removed the ram air cap on top of the carb because it didnt fit).
I have tried several different things but still no luck.
I have replaced my air dam, Bipassed the relay for my electric fan (it now runs when the engine is on),removed my air conditioning rad, bought a new rad, changed my thermostat then totally removed it (which helped a little).
Some people say to replace the single fan with a double and others say to upgrade my rad.
I live in cold Canada so would like to run the fan thru the relay to keep warm when necessary.
Any suggestions?

[george kujanski]

Welcome to the forums. Interesting to hear something besides a Pontiac motor overheating.
From your description, I would check to see if the water pump is working. Sometimes the impeller gets loose on the shaft.

Do you have an air pocket, Prob not once the thermostat is removed, tho. How are you determining that it's truly overheating? Bad gauge/sender?

Does it overheat at idle/low speed or at high speed or both?

George

[cjheidt]

It is overheating alot on idle, at high speeds not as much but still ocurring, actually when ever the outside temp is warmer then say 15 celsius.
I am determining that it is overheating by the gauge then by inspection because steam starts to escape from the hood and the temperature inside the car gets warm also.
I have replaced the water pump already, didnt help tho.

[george kujanski]

I would suggest reading the "chalk another one up for the cast impeller" thread in this same forum. If you ignore all the instances particular to the Pontiac water pump, there are a lot of sugesstions for causes of overheating which apply to all engines. It reads like a novel, but there are good ideas there.

George

[cjheidt]

Thanks George, I will check that one out.

[Mr_GTO]

Sounds like you might have issues with the engine rebuild.

I would install a higher capacity radiator. The fan should be fine. I would put a 160 thermostat back in it, because otherwise the coolant will flow without staying in the radiator to cool it enough.

Also, make sure you have the correct water pump for the year application. Also, is the timing set correctly? And a cast impleller for the water pump won't matter since this is not a pontiac engine it is a Chevy engine.

Ever replace the radiator cap also?

[cjheidt]

Hi Mr GTO
The timing seems to be set correctly as the engine just purrs and stops as soon as the engine is turned off. I did try replacing the rad cap also with no luck.

I have heard that removing my thermostat is supposed to contribute to overheating but for some reason in this case it actually helped, dont quite understand why but since it helps I will do it for now (quick fix until I can solve this mystery).

The thing about the TA is that it has no grill on the front, so no air flow, probably not a great way to design cars. Oh well.

What kind of issues could there be with the rebuild? I had three different mechanics working on it as the first guy was kind of an idiot. He squished some of my wiring between the tranny and the motor upon re-installation and didnt even notice.I wouldnt be surprised if he did some other knucklehead kind of work on the motor too.

[buwalda]

84,
You could have something outside the cooling system causing your problem, especially since you say the engine is rebuilt. What springs to mind is a blown or leaking head gasket, leaking combustion gases into the coolant. This will make it heat up real quick.
If it is only the cooling system itself, the fact that you ran cooler without a t'stat indicates the t'stat was causing a resriction to water flow, so the pump may be inefficient or the wrong one. More flow=better cooling, & this has been proved time & again by companies specialising in cooling.

[trans am ed]

here a trick i heard about that has worked for me. chevy has a by-pass in the front of the block under the lower water pump bolt. tap the hole and put a pipe plug in it, then drill about 2 or 3 holes in the thermostat. all the water will go though the radiator insted of by-passing it before the thermostat opens. this has worked for me in the past. ed

[jhny7]

IMHO if you have steam rising from the engine you have a leak some where an do not have a closed sys.Steam allows coolant to be boiled out of your sys reducing coolant level ch your heater core also as well as the entire cooling sys.