hye guys i'm having a hard time diagnosing the problem with my 92 buick roadmaster with the L05 v8. i have a pretty steady coolant leak coming right from the bottom(center and front of the motor) of the oil pan gasket, right behind and below the crank. does anyone know what the cause of this could be from. i'm really confused. help! thanks in advance. Dave

if it looks like a pure coolant,
it cant be from oilpan. if it looks like its mixture of coolant and oil,
then u might have leaking headgasket causing coolant to flow into oil passage. very expensive repair..

if the coolant looks pure coolant color(green, orange),
it must be from somewhere else thats just dripping out.

my car's been doing the same kinda thing for long time,
and the shop told me its coming out of the head,
but its leaking only because my car runs too warm.

they did a pressure test through my radiator and found that
when my car goes over certain temperature the pressure builds too high that
it just leaks out little by little.. but it doesnt leak inward thank god though.

it look like pure coolant but i can never catch where it's coming from honestly. when i get under with a light and let it run i can never see a drip. but it always magically appears when i drive it and when i arrive where i'm going it's always in the described spot. i can't even catch it when i let the car keep running after it show itself.

hey my responses to some questions over on impalassforum, should help with some insight.

-i lose a quart of oil every few days (heavy blue smoke on start up) the oil itself smells normal on the dipstick. the antifreeze looks normal too. some brown in it but it might be the gm stop leak tablets i tried to no avail. there are light bubbles on oil dipstick and coolant radiator when running. i have a CEL on that says the o2 sensor is running lean? not sure if that is tied into or not. BTW i've replaced the water pump, t-stat, hoses, and radiator already.

-mileage is unknown. i bought it used off of a guy and i didn't realize that the odom was broke. in a year it's only turned about 500mi. it's stuck at 161,000 or so (it turns on and off). and as much as i drive it should be at showing at least 180k+. and that's just with me i dunno how much it was driven or how long it's been dead. so i'd guess well over 200k.

oops

oops

here are some pics of my spark plugs. these are from the drivers side. going from the front bumper back. someone tell me wtf is going on. these were installed less than a yr ago (like 8-9mo). the dist cap and rotor and wires were all done at the same time. they're ac delco rapid fires.

here are some more pics of my spark plugs. these are from the passenger side. going from the front bumper back. someone tell me again wtf is going on. these were installed less than a yr ago (like 8-9mo). the dist cap and rotor and wires were all done at the same time. they're ac delco rapid fires.

blue smoke off exhaust is a sign
of valve steam seal leaking.

as far as i know its not a easy fix and expensive repair(400$ or so).

as for coolant leaking,
i might have the same problem as u do.

if u take a close look, i think it should be coming off
the head. check around the head and it might be leaking from there,

a mechanic told me that when my car gets too warm(not overheat),
my coolant pressure goes higher than it supposed to and make the coolant
leak outside from the headgasket.
according to his pressure test,
as long as my engine stay below 230F, my pressure is within the limit
and it will not leak.
so with this said i decided to buy a jet cooling setup..

hopefully this might be the case for u too,
then ur solution is easy, just find a way to run ur car cooler,
there's lots of way u can do that.

but as for ur blue smoke, thats just definately the valve seal,
and most likely it has nothing to do with the coolant
and u probably want that fixed.

good luck

If the pressure in the cooling system gets too high, the radiator cap vents into the recovery tank. If coolant escapes anywhere else at any time, regardless of what temperature it happens at, then you have a leak that needs to be fixed. Running the car cooler isn't a solution.

ouch..

could it be my radiator cap?

Look where the coolent enters the intake manifold it might be runing from there down the front of the engine, let it get hot and then listen for a HISS as well. I had a small pin hole in mine I couldn't findit when it was at idle. But i was steady losing water, and there was a stain on my intake manifold, look for water on top,
Also along the sides of the engine there are things called Freez plugs, look at them think there ar three to a side, larger than a silver dollar, they need replaced from time to time, you can have a mechanic put them in (what i recommend) or if you wanna try it you can.

Coolant in the oil pan area could be coming from a freeze plug, a drain plug, or maybe a headgasket or fitting in the coolant ports in the head.

There's a tool you can buy/rent/borrow/improvise to pressureize the cooling system with air from a hand pump that would help locate the leak.

Probably not, the radiator cap should open at about 16 psi or so, and your gaskets should be good for well above that pressure.

Your mechanic should have done a proper pressure test on the system to locate the leak.

he said the pressure builds too high
only when my car gets hot,
and that fan coming on at 235F is too late.(which i kinda agree but thats the factory setting right?)

up to that range of temperature, 235~,
he said my pressure is fine
and doesnt leak so I dont know..

Check your water pump and check the level of coolent in your radiator

Those spark plugs are from a bad head gasket. That is excatly what mine looked like on my 85 suburban. If your getting bubbles in your overflow tank when it warms up that. Is a dead give away for a head gasket. I did not have oil in water or water in the oil. But it was a head gasket.

On a fprmula I parted out. Oil was clean and radiator just keep loosing water. When it warm upit would bubble in the overflow tank.

Just my two cents

So what did you find out.