Coolant Leaking/Burning

**bobh13908** · 10-05-2011, 03:08 PM

HELP!! I have a 1999 Z28 w/ls1 stock. no mods. It seems to be losing coolant quickly. It doesn't leave puddles anywhere I park. I don't see anything on the motor that looks like a blown gasket. I just cleaned the engine off today so that I could get a better look, but I'm not sure where to look. I know the head gaskets, intake gaskets, and water pump are the normal places to look and I've checked all the hoses and the radiator. Does anyone know the best way to detect a coolant leak/where it's burning. Do they make a dye that you can put into the coolant to find out where it's leaking like they do with your a/c lines? HELP! Any suggestions would be great!!!

**Knight** · 10-05-2011, 03:12 PM

First off, check the oil. If you see a milky residue, that is a sign of coolant contamination. You could also check the exhaust, white smoke indicates burning coolant.

**bobh13908** · 10-05-2011, 03:19 PM

I checked the oil and the exaust, I had my roommate drive behind me and he didn't see anything coming from the tail pipes. I noticed that it seems to be coming out of the top of the over flow bottle if I fill the radiator directly when it's cold and then let it warm up.

**SteveC** · 10-06-2011, 04:08 AM

You are probably burning a small amout through the cylinder heads, especially if it is a high milage vehicle.

SteveC

***SMWS6TA*** · 10-06-2011, 06:39 AM

You could do a cylinder compression check. It can assist you in finding out if you have one without tearing into the head blindly.

As a rule, most engines should have 140 to 160 lbs. of cranking compression with no more than 10% difference between any of the cylinders.

Low compression in one cylinder usually indicates a bad exhaust valve. Low compression in two adjacent cylinders typically means you have a bad head gasket. Low compression in all cylinders would tell you the rings and cylinders are worn and the engine needs to be overhauled.

How many miles does your engine have?

How often do you have to put coolant in?

When's the last time you serviced the coolant? Should be done every 3 yrs.

Only other spots besides the one's you mention are the coolant tubes under the intake. It's possible they could be leaking and the heat of the engine is evaporating it thus no puddles. But again I need to know how often you have to refill the coolant to make a better guess.

***SMWS6TA*** · 10-06-2011, 06:41 AM

also when your engine is running look to see if you have air bubbles in the radiator. If so, you have a head gasket leak.

**89RS&98Z28** · 10-06-2011, 07:04 AM

"I noticed that it seems to be coming out of the top of the over flow bottle "

Get a new radiator cap. After doing this you will find your leak.

**bobh13908** · 10-06-2011, 04:34 PM

it has 160,000 miles on it, i just flushed the entire coolant system out this summer and I have to put coolant in quite often, i took it on a road trip and had to put coolant in every 200 miles or so.

**Cutlass** · 10-06-2011, 06:13 PM

Air pockets in the cooling system?
the best way to test for a cooling system leak is to use a pressure tester. It pressurizes the cooling system to about 15 psi and then you can look to see if the pressure drops or if coolant starts dripping on the ground.