On my non EGR 1992 I noticed the other day that I am significantly down on coolant. I have not noticed any coolant leaking on the ground, at least not any amount that was noticable over the slush, snow, and salt lately. I really don't see any major areas of concern while looking under the hood. The car has been running well and I have not had any indications that something was not right.

After doing some searching it appears that although the intake is not as prone to crack on the Series I engines the upper intake gaskets are still prone to failure. Is that where I should start? Tear the top end appart with the intention of replacing the upper intake gaskets and see if I find something else from there?

What else should I look for as a possible problem?

I looked at the plastic fitting on the passenger side of the engine but It doesn't look too suspecious to me. If it failed wouldn't it be a noticalbe coolant loss and puddles on the ground?


Thanks for the help,
Ryan

A leak may not be obvious, even while looking under the hood while the engine is running.
Look closely at the upper and lower radiator hoses and where they're clamped to the radiator, the water pump, and coolant reservoir and its hose.
When the plastic coolant bypass fitting failed on my '92, it cracked and leaked slowly. A little coolant could be seen just above the water pump.
The heater lines or heater core are another possibility; if the heater core is leaking, there may be coolant under the front passenger floor mat, and you'd probably smell coolant when you drive the car.

If you don't find an external leak, check the oil for contamination due to a possible internal leak.

Even your TB gasket could be leaking into the TB. There'* a coolant path there.

I'd go with the top end teardown. Does the EGRless 92 have a seperate upper/lower, or is it all one piece like the earlier gen? Anyway, if it is upper/lower, I'd replace the upper and lower intake manifold gaskets (including the gaskets UNDER the lower between it and the block) and the TB gasket.

That'll do you for another 200k

Is this the first L27 that we've seen here with a coolant issue? First one that I've heard of. Quite rare...

No, the L27 needs lower intake manifold gaskets at 150-200k miles typically. Alot of motors do.

Wow! Thanks for the quick replies.

I forgot to mention that the car has about 140k on it and I see not visible sign of coolant contamination in the oil, it is not milky or overfull (I think I will send the oil out for analysis to be certain).

Thanks for the help so far. I will do a little more snooping around under the hood today to see if I can locate the source of an external leak.

If I keep the car filled up with coolant, do you think there is any real harn in driving it at this point?

Keep a very sharp eye on it. The cool thing about the L27 is that when you open the top end to change the gaskets, you'll see the evidence and locate the leak. The runner/chambers in the lower intake manifold will be clean where the leak was

I would have to suspect TB gasket as a possible cause. when the car is running, cna you see coolant running down the trans? if so there is your problem

He said he had no external visible leaks, so if it'* the TB, it'* leaking to the INSIDE.

What is the rate of coolant loss?

Big internal leaks can ruin your engine with the turn of the key.

If you are losing coolant really fast, there is a good chance for hydrostatic lock if the leak is into a combustion chamber, or serious bearing damage if the leak is into the crankcase. Does the oil look normal? Milky or frothy? Is there more condensation than normal under the oil filler cap?

If the oil is contaminated with coolant, drain it immediately and set about finding and fixing the leak.

If you suspect a big internal leak, don't start the car. The safest course is to have it towed to a shop for a pressure test. If you are poor, like me, before you do that, you can check some stuff yourself. You might want to pull the plugs after the car has cooled down to look for evidence of coolant in the combustion chambers. The safest way is to turn the engine over by hand with the plugs out. You won't damage the crank or rods that way. If everything looks dry and OK, and the oil looks OK, too, drive it in for a pressure test.

If you have even a small leak into a combustion chamber, you should be able to detect the sweet smell of coolant in the exhaust. Larger leaks into the combustion chamber will result in white smoke out the tailpipe.

If the leak is external, you can often smell it. If the heater core is seeping, you shold smell that easily, too. Did you look really carefully around the water pump pully for evidence of coolant loss? You may have something really easy like a water pump going bad that only leaks when you are running. That would be good.

Let us know.

[edit: Geez, I gotta be quicker with my replies - in the time I spent thinking about this there were 8 other responses!}