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Discussion Starter · #1 ·
I close to giving up and taking my car to the shop. I just finished installing new head gaskets and the car is still running to hot. I checked the aluminum heads and block deck for flatness and saw no issues. I torque the heads down per instruction from trick flow. I back my timing down a bit and saw no benefit. I post before what I have for a cooling system, but I'll post it again. A summit univ alum radiator, flow kooler alum high flow water pump, mach pulley system ( standard drive), derale electric fan w/ rich 66 shroud setup, stewart 180 thermostat w/ bleed holes, high pressure 27 lb radiator cap, I put in prestone 50/50. I also tried removing the shroud and putting the fan back on the radiator but saw no difference. I have run through what limited knowlegde I have and cant figure this out. Any other ideas I may have missed here?? thanks

Len
 

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hey len,
try to break the problem down to analyze it more easily.
when did the problem begin?
did you change many things at once or everything(cooling related) at the same time?
is everything new or are there some used(swap meet parts) in there?
are you sure the thermostat is opening?
does it run hot when moving or just sitting?
you get the idea............
heres a couple of things to try-
1- try the thermostat in a pot of boiling water and test it with a second thermometer to be certain it's opening properly.
2- see if the fans will hold a piece of paper to the outside of the rad when parked.are your fans rotating the right way to pull the air in?
3-is it possible that a rad hose is sucking itself flat(restricting flow) under acceleration?
4- are you running a shroud?
5-how close are the fans to inside of the rad?


thry this stuff and get back to us.don't get frustrated...there's lots of knowledge here and we'll help you if we can.:yes:
leftcoast carl.
 

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Discussion Starter · #5 · (Edited)
It heats up doing both but worse when moving. The march setup is for std rotation and the water pump is designed to move water either clockwise or counterclockwise. I watch the water flow with the cap off and it is flowing well when the therm opens up. I did all the changes at once, since the old setup was not very good when I bought the car about year and half ago. I also change the temp gauge just in case the old one was reading wrong.

Len
 

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It heats up doing both but worse when moving. The march setup is for std rotation and the water pump is designed to move water either clockwise or counterclockwise. I watch the water flow with the cap off and it is flowing well when the therm opens up. I did all the changes at once, since the old setup was not very good when I bought the car about year and half ago. I also change the temp gauge just in case the old one was reading wrong.

Len
where are you measuring the temperature? at the intake?
feel the rad core exterior when it's up to temperature to ensure there's no 'cold'spots(indicating a blockage).
i question the clockwise/counterclockwise thing(no offenseintended friend:)),as an impeller in a waterpump is designed to move water in one direction only(one way or the other) but not universally (one pump that's reversible) as far as i know.have you talked to the manufacturer?
did you gasket match the cylinder heads before installing the head gaskets?
have you pressure tested the system to ensure there's no leaks?


just a few more ideas....:eek:
leftcaost carl.
 

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have you tried a good old mechanical fan?

also, I heard that if its getting hot at highway speeds its because a baffle at the bottom of the bumper (or somewhere aroud there) is gone.
 

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I have never heard of the either direction water pump either....seems the general shape of a water pump impeller would only work well going one direction
 

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Do a cooling system pressure test or have one done.
 

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It may sound counter intuitive but retarding the timing will make it run hotter or at least raise exhaust gas temps.

The laws of thermodynamics apply to all heat exchange systems. Your heat sink (radiator) must be able to shed more BTU's than the heat generator (engine) produces.

Provided you don't have something simple as an air pocket in the system or any of the other mistakes suggested above, it may be as simple as the new radiator does not have sufficient thermal capacity for your engine and/or you aren't moving enough cool air across enough surface area of the core to carry away the heat.
 

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Can you list the part number of the water pump? I've never heard of a water pump that will work in both directions. Not sure, but a part number may help us figure this out.

Jim Smith
 

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Is it possible that you put a head gasket on wrong?

Somewhere in my "gray" matter, I seem to remember that I had an overheating problem, due to head gaskets; but was probably a 400 CI small block.
 

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Exactally how hot is it running? What fan are you running? How big, and CFM rating? You do have a spring in your lower radiator hose correct? What convertor and rear gear are you running?
 

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Got the same problem with my 64 C10 with 350. I believe some of the coolant passages in the block are plugged.

I band-aided it with an oil cooler. made a huge difference, but will still overheat at idle.

A couple of tidbits I have gleaned in my process:

an electric fan in front of the radiator is more restrictive compared to having it behind the radiator.

Be sure your fan is not pushing air the wrong way

serpentine belts require a left-handed pump and fan

It is possible to push the water TOO FAST thru the radiator, and it won't cool

try it with and without a thermostat and see what you find.

lower hose can collapse from suction causing restriction
 

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Discussion Starter · #18 ·
Here's the pump Im using: http://store.summitracing.com/partd...925060+4294840140+4294903547+115&autoview=sku

I have a derale puller fan mounted on the rear of the radiator with the shroud made by rich 66 here on the site. I dont currently have a spring in the bottom hose, however I had a stainless flex hose on until I popped off yesterday. here's the fan I'm using.http://store.summitracing.com/large...+Output+Rad+Electric+Fans&img=der-16217_w.jpg It is supposed to be a 2400 cfm rating. Thanks for the suggestions, I'm going to have the shop check everything that you all suggested. Im just getting frustrated with this car, because I've put about 14k in it and I can't seem to get it out of the garage without some sort of issue. Again thanks for all the suggestions. I'll let everyone know what it turns out to be.

Len
 

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I simple check is to remove the radiator cap (cold engine). Start it up and let it get up to temp. If it wont get hot enough at idle just idle at a higher rpm, a friend on the throttle helps so yer not having to hold the carb. And look down the hole of the radiator. You should see when the stat opens. There will be alot of turbulence. You may want to remove some coolant so its about three inches below the neck. JR
 

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have you tried a good old mechanical fan?

also, I heard that if its getting hot at highway speeds its because a baffle at the bottom of the bumper (or somewhere aroud there) is gone.
Thats what solved my heating issues.I went to a clutch fan and watter wetter...no more over heating.Its worth a try...it'll cost you about $50.
Ps you may have an air bubble in your system.Jack up your front end start up your car and let it come up to operating temp.good luck.bm
 
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