LS1 swapped E30 - overheating

[kristov]

Hi,

I need some expert advice regarding my overheating problem. The engine is a bone stock 2002 Camaro Z28 engine.

Diagnosis so far using a pressure gauge on my cooling system and HP-Tuners revealed the following results:

• If I let the car idle for a long time (approx 60. min) it will reach a terminal temperature of 241 F and 23 PSI.
• After turning the cabin heater on for a while it will drop to 207 F and 11psi.
• It does not smoke white, mix oil/coolant or use a noticeable amount of coolant.
• When I go WOT a couple of times the temperature rises quickly and it needs a long time to cool down to normal running temperature again.

Any ideas on what could be wrong?

• Head gasket?
• Air in the cooling system?
• Crack in head or block?

Help would be greatly appreciated before I tear it down!

[e30_302]

What radiator are you using? Sounds like a lack of cooling capacity.

[kristov]

What radiator are you using? Sounds like a lack of cooling capacity.

I have this radiator in my car: http://www.summitracing.com/int/part...01-h/overview/

Core Width (in):19.000 in.
Core Height (in):15.500 in.
Core Thickness (in):2.680 in.

[1990m3]

do you have an electric fan and if so, is it running through the PCM with low and high fan speeds?

[kristov]

do you have an electric fan and if so, is it running through the PCM with low and high fan speeds?

Yes, dual fans controlled by PCM. Temps lowered through HP Tuners.

[jntar]

Could be air in the cooling system not allowing the thermostat to open. (Bleed system)
Could be a bad thermostat. (Replace with new or maybe try running without one for a short test period)
Could be a bad water pump. (Replace)

Since you're not losing coolant I dont see it being a rad cap issue.

[jalopi]

What temps do the fans come on at? Also, what's their CFM rating?

IMO if the teeny "radiator" in your dash and the squirrel cage will reduce your temps but the dual fans on your reasonably sized radiator won't... I'd say you've either got some sort of coolant flow issue to the radiator -or- the fans don't work worth dick.

[kristov]

Took another block test as the first one was inconclusive - would you say this one is conclusive?

For this test I held the engine at 3000 rpm and the results below appeared in about 15-30 seconds.



This happend when I tried to bleed the system a last time - doesn't look right or?

http://youtu.be/WPNuehT2-Tk

[e30_302]

Keep bleeding. Make sure the water temp is up high enough for the thermostat to open.

[kristov]

Keep bleeding. Make sure the water temp is up high enough for the thermostat to open.

The thermostat was wide open in the video above. Engine temp approx. 207 F.

If I let it idle there are no bubbles - give it som revs and it bubbles like in the video.

[e30_302]

Is the radiator funnel higher than everything else? May need to jack the front up a little.

[kristov]

Is the radiator funnel higher than everything else? May need to jack the front up a little.

Yes.

[bmk]

It does sound like your car is overheating, however LS's run much hotter than other engines normal operating temp its 200-230 depending on if your using AC and what not.

[bmk]

My gut tells me your thermostat is closing slowly. I would buy a new 160 degree thermo and see whats up.


EDIT: meant to say 180.

[e30_302]

A 160* tstat will never close, might as well not even run one (which is also a bad idea).