car is overheating

[lt1chevelle]

ok so my car is overheating it is running at 220-230 its a 95 lt1 motor. i have bleed the bleeder 3 times and get nothing but water. the expantion tank is at the highest spot and its above the radiator by 2-3in. do you think i need to lower the radiator more?its really starting to frustrate me i cant seem to find the problem.

[alittle1]

Are you looking at the dash gauge? Did you check the water temp with a mechanical gauge? Cooling fan running? Nothing blocking the rad. Is that temp you're getting, running on the hwy? or just sitting in the driveway??

[lt1chevelle]

temp is from a mech gauge not the stock ones, fan is running. and this is the rumbers when i am driving the car

[shep]

I have read that the LT1 is sometimes hard to get burped. Might try parking with the nose up hill over night and try bleeding again. Other than that I got nothing.

[lt1chevelle]

thanks ill give it a try

[paul67]

Have you cured it,does the engine still have the steam lines,is it a side to side flow rad or up and down,does the fan have a cowl around it,are the sides of the rad blocked so the air is forced through the rad and not around when driving,is the thermostate missing if not have you drilled the 1/8" bleed hole in it,are you running A/C,sorry for the long list but these need to be known, I have a 95LT1,in a 67 camaro,I'm using a side to side alloy rad for a big block,level with puke can , no stat but will fit as this can cause air bubbles in the water raising running temp, also run water as this let engine run cooler by about 20f over coolant. This is what I have found out reading mags on said engine.

[BlueBull]

A friend of mine had similar problems a while ago. I'm not sure if this is useful for you but anyhow....

The reason for his problems was the timing. I think the ignition was to late and after adjusted it to correct settings the temperature went down dramatically. I could not even imaging this could happen but it did.

[alittle1]

Did this happen all of a sudden or just over time? Did you make a modification to the car or engine? Let's have some background from you on what took place before.

[megaladon6]

what temp should it be at? that's in it's original car and everything. a lot of GM's in the 90's ran at 210*. i think it started with dex-cool but not too sure. where is the temp sensor located, the stock location or...?

[lt1chevelle]

no i have not solved the problem. and this just started ever since i got the motor back together. the motor is not stock the heads have been ported and polished and has bigger valves. the cam is a gm847 (specs are 590/595) has roller lifters and roller rockers with 37lb ractronix injectors and a holley 52mm tb with long tube headers. the car should be close on its timming i had the comp tuned for the motor but probaly could use a dyno tunning. as for the thermostat being in yes it is its a 160 degree one but i did not drill a hole in it? sorry for the late response i was gone for the weekend

[lt1chevelle]

temp sensor is in the driver side head

what temp should it be at? that's in it's original car and everything. a lot of GM's in the 90's ran at 210*. i think it started with dex-cool but not too sure. where is the temp sensor located, the stock location or...?

[lt1chevelle]

yes the motor still has the steam lines, i have an expantion tank that the line runs into.no the fan dose not have a cowl aroung it.i dont get what you mean by the sides on the rad? no a/c. the rad is not stock its a becool.

Have you cured it,does the engine still have the steam lines,is it a side to side flow rad or up and down,does the fan have a cowl around it,are the sides of the rad blocked so the air is forced through the rad and not around when driving,is the thermostate missing if not have you drilled the 1/8" bleed hole in it,are you running A/C,sorry for the long list but these need to be known, I have a 95LT1,in a 67 camaro,I'm using a side to side alloy rad for a big block,level with puke can , no stat but will fit as this can cause air bubbles in the water raising running temp, also run water as this let engine run cooler by about 20f over coolant. This is what I have found out reading mags on said engine.

[HILROD]

Did you make sure the water pump is the right one for the belt setup you are using? Maybe your pump is the wrong rotation.

[lt1chevelle]

its a electric pump, and yes its working

Did you make sure the water pump is the right one for the belt setup you are using? Maybe your pump is the wrong rotation.

[MrQuick]

How much does your fan cycle during?

I think you might have a combination of problems. The first thing I see is the 160 degree t stat and large tube radiator.

The t-stat needs to close to stop circulation so it gives the coolant in the radiator time to cool down. Thus transfering heat to the fins.

Right now your t-stat opens up at 160 and stays open, the radiator flows so well the coolant is just passing with very little heat transfer. Even if your fan is constantly running.

[paul67]

Just hunted down some info ,the opperating temp for this engine is 220-235 ,low speed fans on 226 off 221 high speed 235 off 231.

[lt1chevelle]

my fan turns on when the car is running. you think i should go with a 190 degreet t-stat?

How much does your fan cycle during?

I think you might have a combination of problems. The first thing I see is the 160 degree t stat and large tube radiator.

The t-stat needs to close to stop circulation so it gives the coolant in the radiator time to cool down. Thus transfering heat to the fins.

Right now your t-stat opens up at 160 and stays open, the radiator flows so well the coolant is just passing with very little heat transfer. Even if your fan is constantly running.

[streetk14]

I have a 160 t-stat in my LS1 with a Griffin radiator and spal fans & it never goes over 180. Temp sender is in the rear of one of the heads. I don't know much about the LT1 motors, but I do have a very good understanding of cooling systems and such.

Am I wrong here, or does the LT1 have that funky reverse cooling system (or was that the LT4) ? It that were the case, I would make sure the pump is flowing the right direction.

Does the radiator have good flow at both idle and when raising the rpm a bit? You should see a good amount of flow from the upper radiator hose with the t-stat open. (edit: you have an electric pump and I'm an idiot )

I am assuming that the t-stat is opening and that both radiator hoses are warm when it is at it's operating temperature. Just wanted to check.

If you have a heater, make sure it gets nice and warm. If it doesn't, there could still be air in the system.

When does the engine heat up? Is this just the temp it runs at at all times, or will it creep up to this point at idle and lower speeds? Will the temp come down at all at freeway speeds? I'm just trying to get an idea of whether it is a coolant or air flow problem.

Andy

[lt1chevelle]

i do have a heater but the hoses are not hooked up. the car heats up from start up i drove it for about 10min and it got to 180 but it will keep going. i was driving about 55mph and it was still reaching 220 and look to still be going up but i stoped. i am just real worried i am going to warp a head or blow a head gastket i have way 2 much money in the heads and motor and i cant afford to fix it right now. do u think maybe i have the wires on the pump switch up and its rotating the wrong way? both the lower and upper rad hose are both warm.also let me add the car has no hood on it and its still getting this warm. im going crazy over thing problem

I have a 160 t-stat in my LS1 with a Griffin radiator and spal fans & it never goes over 180. Temp sender is in the rear of one of the heads. I don't know much about the LT1 motors, but I do have a very good understanding of cooling systems and such.

Am I wrong here, or does the LT1 have that funky reverse cooling system (or was that the LT4) ? It that were the case, I would make sure the pump is flowing the right direction.

Does the radiator have good flow at both idle and when raising the rpm a bit? You should see a good amount of flow from the upper radiator hose with the t-stat open. (edit: you have an electric pump and I'm an idiot )

I am assuming that the t-stat is opening and that both radiator hoses are warm when it is at it's operating temperature. Just wanted to check.

If you have a heater, make sure it gets nice and warm. If it doesn't, there could still be air in the system.

When does the engine heat up? Is this just the temp it runs at at all times, or will it creep up to this point at idle and lower speeds? Will the temp come down at all at freeway speeds? I'm just trying to get an idea of whether it is a coolant or air flow problem.

Andy

[paul67]

The engine does have a reverse cooling flow.