Replaced the rear main oil seal on my 82 firebird V6 two weeks ago. Those two part seals aren't a great job and the seal leaks a little oil still. The main issue here is a small coolant leak. Nothing leaks from the seal when the engine is running but when it is shut down some oil starts to leak out. After about nine or so hours after the engine has being switched off small amounts of coolant drip onto the fly wheel on the engine side and onto the ground. I have taken off the dust cover but cannot see anything. I spend an hour with a torch last night checking all all around the engine and transmission looking for a leak but found nothing. This is doing my head in!!!. Where is this leak coming from and why does it only appear hours after the engine is switched off?. Anybody got any suggestion?. Is there a freeze plug at the rear of the engine?. Maybe I done something when I raised the engine to get out the oil pan.

I'm pretty sure this will not help you, but I just finished getting my engine running after 2 years of standing, and I had a water leak. Turned out to be the hose running into the heater matrix being loose. Just thought it might be worth a look, sometimes the obvious things escape us. It took me 2 hours before I spotted it! I nearly started to take things off to see where it was coming from.

I checked all those hoses and they are fine. I lied under the car while it was running with a torch and there is no leak from any of the hoses. What about the intake maniford can a leak come out there?

Gerry.

V8's (assume V6's too) have core (freeze) plugs at the rear of the engine too...no way to get to them unless you pull the flywheel/flexplate off.

It's possible, there are water jackets running through the intake manifold. I think unless the manifold itself is ruptured, the only place it could leak from (not counting hoses or thermostat housing) is the cylinder head mating surface on the intake. The chances are though the water would gather on the top of the engine and you'd see it. Have you checked the water temperature sender? If the water is taking such a long time to reach the floor, it's also possible that it's being thrown about the engine bay a bit, and has to make it's way down....maybe the water pump? Also, as just mentioned, the freeze plug which I have to admit escaped my memory for a while there

I think there is a dye available you can put in the water system which glows under ultra-violet light. That would probably make tracing a water leak quite easy. Not sure where you get it from though....anyone?

I've had a coolant leak from the rear of my 305 V8 engine (Chevy Caprice daily driver) for a while. It is coming from the intake manifold gasket. Yours could be from the intake man gasket, like mine, or could also be from a freeze plug.

Like your leak, mine only leaks when cold. Must be that the hot engine expands and seals up the gap until it cools down again.

GTA88

Thanks guys for your input. I have checked all around the engine bay and no sign of a leak, checked water pump, sender unit thermostat housing, heater core and all pipes. Is it possible to tighten the bolts on the intake manifold?. I suspect that it is coming from a frezze plug though.

Did anyone try the stuff you mix with the coolant that is suppposed to stop leaks?. I tried a product called Radweld before but didn't find it done anything. Anyone had any success with these type of products. THe leak isn't that big, just very annoying. I hate looking under the car and seeing coolant on the ground.

Gerry.

I used a product called BarsLeak , a brown fluid in a bottle, which worked very well to stop my intake manifild leak. But I think it caused overheating, on long trips, due to coating the entire cooling system and reducing heat transfer by the radiator.
I eventually put in a new rad, which stopped the overheating.

I have used a product called radweld which is readily available over here. I have done about 200 miles on the car since I put the stuff in the radiator and it still leaks. I did notice that the temperature gauge started to read slightly higher now that you mentioned it. How long did it take for the Barsleak stuff to work on your car?.

Gerry.

Gerry,

The Barsleak takes effect after one driving session. You dump it in the rad, go for a drive for 10 minutes or so, herat the coolant up, circulate it everywhere, then you can keep driving or shut down the car. The leak should be sealed the next time you start up. It sealed up my leak after I did the above. I think I drove it arounf dor 10 minutes and shut it off. It kept the leak at bay for about 2 or 3 years, then the leak came back. I am afraid to use it again due to the overheating problem. And I don't want to spend $$ to fix the intake man. This an OLD car..... my daily driver Caprice.

The stuff I used is in there a few weeks and I drove the car over 50 miles since then. I can flush the system and try other stuff lik BArsleak if I can find it here but am I goming to risk over heating also by have too much of the stuff in the system. I must look into this.

Thanks for your input.

Your car might not overheat. I've used sealers in other cars, and not overheated. I've only overheated in my V8 Caprice, and only on long trips when the temp was over 70 degrees F.

Worst case scenario : if you start overheating, you can try replacing your rad (which I had to do, after flushing the sealer out). I got a brand new rad for only $72 U.S., :lala: thanks to the miracle of capitalism and the offshoring of U.S. manufacturing jobs. My new rad was made in Mexico.

How is the cost of autoparts in Ireland? Coming down lately?

I don't know if you need to flush the other stuff out.



My 2 cents worth........