FbodyAttraction

iTrader: (15)

Engine started to overheat, found about a half gallon missing from my coolant. Its not leaking externaly, no puddles or drips. I checked the oil, looked good, no coolant. My exhaust doesnt smell funny, and my car is otherwise running as it always has.

I filled it up last night and when I opened it up today It had a vaccumm (negitive pressure) in the system and the coolant was lower by just a little. After running the engine the coolant level rose to normal.


Im about to replace the cap, thinking its that. What do yall think is going on?

joshp14

iTrader: (5)

Try to borrow or rent a cooling system pressure tester. You can pressurize the entire cooling system to the 16 psi spec and see if it drops. It also includes an adaptor to check the cap. If you dont have a tester, I would replace the cap and see if it fixes it. Its cheap and I've seen them go bad on several f-bodies.

98boxer

iTrader: (7)

Did you recently change the coolant?

Did you add coolant to the reservoir?

94'BLKBRD

iTrader: (76)

Pressure check the cooling system would be your best bet.

needadvice

Be careful if you pressure check the system. If a blown head gasket is the culprit you could fill a cylinder with coolant, then when you start it up you could hydralock the engine and damage it badly if not total it. Take all the spark plugs out if you pressure test it.

FbodyAttraction

iTrader: (15)

So I replaced the cap, but coolant is still leaking, at a rate of 1/2 gal every 1000 miles... How do I find out where its going?

needadvice

If you're sure its not leaking into the oil or can't see any external leaks....you may have a blown head gasket and its going out the exhaust. I'd let it warm up to operating temp and rev it in park and see if you see any coolant coming out of the exhuats pipes.

Also, did you do a pressure check as mentioned?

MUSTANGBRKR02

iTrader: (91)

Have you checked your passenger floor?

SpaZMaN

iTrader: (5)

heater core leak?

MUSTANGBRKR02

iTrader: (91)

possibility its going somewhere.

Formula413

iTrader: (1)

FWIW, my other car was loosing coolant, no puddles/drips, pressure checked ok, turned out to be the radiator, it was leaking from the seam between the tank and core, only when hot. But as was said be careful pressure testing it, in case you do have a bad head gasket.

ae13291

iTrader: (8)

take out each spark plug and look to see which one is the cleanest plug, if its leaking coolent into the combustion chamber that plug would be clean!

FbodyAttraction

iTrader: (15)

I just got a pressure checker. Im going to wait till morning for it to be cool to check it. Heater core checked out, no problems there.

Thing is, the engine is running fine, the exhaust is not smoking. Hmm.

BigBenz

iTrader: (7)

head gasket

SS#2906

iTrader: (53)

Wouldn't smoke shoot out the exhaust if it was a head gasket?????

needadvice

Not really, it would have to be a huge leak. Although, on early morning start-up you could see little white-ish clouds coming from the exhaust as it warms up.

modman4.6

if the head gasket was the the culprit then in the morning you would def notice it before i warmed up and thats when the smoke would be there def take out spark plugs before pressure test and is it hot in your area evaporation might be a reason but i dont think it would go that fast i wonder

FbodyAttraction

iTrader: (15)

Well, Pressure test confirms it is leaking. I then started it up while the tester was attached and it didnt bounce back and forth as if air was leaking in.

Should I add that radiator leak fixer material?

Its not smoking at all.

needadvice

Did you take all the spark plugs out while pressure testing it? If it is a head gasket leak you could have filled a cylinder with coolant. I guess since you started it up and didn't destroy the entire engine from hydalocking it there wasn't enough coolant in a cylinder.

I would want to know where its going before I used a leak stopper. However, Barrs Leak with the pea sized pellets in it works amazingly. 2 bottles, but make sure you pour it in slowly, into the radiator fill cap, when the coolant is hot and flowing. The pellets won't dissolve in cool coolant, then you could get a bad clog.

Check your oil again since it leaks somewhere during the press test, could have a cracked block.

FbodyAttraction

iTrader: (15)

After long trips I can smell coolant from the engine bay. I still cant see drops or where its coming from.