Leaking coolant...again!

[flyhigh2chill]

A few months ago I had a coolant leak on my 96 GA 3100. After some research I went with the felpro metal gaskets and did the 3400-3500 manifold swap! Big thanks to sappy and isaac on that! Anyway about 2 weeks later I noticed a little coolant dripping from the car after cooling down from a drive. Since then it appears to have gotten worse! I've traced it to the rear right corner of the engine, sort of below the alt and p steering pump. Anybody have any ideas on what the problem is? The leak appears to be external, not into the engine. Head gaskets? The car has 95000 m. I was very careful when installing the LIM gasket so I'm kinda floored!!!!

[PHatzos]

Gaskets?

Are you sure they are the correct head gaskets? They have to be a specific part # for you application. When the engine gets warmed up, the tolerances get bigger, the coolant is very unforgiving and will find an escape. If all the parts are correct,.... Are the heads warped? They may need to be resurfaced. And finally, ARP makes a very good head stud kit, or even their head bolts. Over the counter head bolts are worthless. Phil

A few months ago I had a coolant leak on my 96 GA 3100. After some research I went with the felpro metal gaskets and did the 3400-3500 manifold swap! Big thanks to sappy and isaac on that! Anyway about 2 weeks later I noticed a little coolant dripping from the car after cooling down from a drive. Since then it appears to have gotten worse! I've traced it to the rear right corner of the engine, sort of below the alt and p steering pump. Anybody have any ideas on what the problem is? The leak appears to be external, not into the engine. Head gaskets? The car has 95000 m. I was very careful when installing the LIM gasket so I'm kinda floored!!!!

[flyhigh2chill]

A little clarification. I only swapped the 3400-3500 manifolds, not the heads. I didn't touch the head gaskets, only the manifold gaskets.

[PHatzos]

My mistake

I did mean the intake gaskets. Usaully at the ends, where the small square coolant ports are, the gaskets won't fit well. There are minor differances between manufacturers. These may cause the leak. You may pay more for the parts, but may I suggest going to the dealer for the oem gaskets. Hope this helps, Phil

A little clarification. I only swapped the 3400-3500 manifolds, not the heads. I didn't touch the head gaskets, only the manifold gaskets.

[rickykline]

i dont trust felpro unless its for something SBC related.. as for our motors.. gm all the way..

[John Michael]

Flyhigh,
I've had what appears to be the exact same situation with my '97 Lumina 3100. I had repleced the LIM gasket last spring with the metal Fel-Pro, but recently I had an external leak same place as you. Just a little below and to the rear of the power steering pump. I figured it was either the timing cover gasket or the head gasket. It did NOT appear to be the LIM gasket again. I gave up and took it to the Chevy dealer.

Dealer confirmed it was the timing cover gasket and I had them replace it. Around $600, I'm going to go pick it up today.

There have been a few other reports on this site about the timing cover leaking coolant. Seems weird, I know, but it happens.

P.S. The mechanic at the dealer said he has also seen the head gaskets leaking in the corners around there too. so don't automatically assume it's the timing cover.

I'm starting to believe the horror stories of Dex-cool. In the last 2 years I've had water pump, LIM gasket, and now timing cover leak. My car doesn't even have 100k miles on it yet. That is pathetic, I think I'm going to do what others have done and flush the Dex-cool out and replace with the green stuff.

[rickykline]

whats the dexcool have to do with it??? i think its more related to improper torque and not enough sealant used...

[tractorman]

You don't use sealant on those new Felpro metal gaskets- or the water passages of ANY LIM gaskets that I'm aware of. I'm gonna have to disagree with some folks here. I've used both the old style felpro plastic gaskets, and the new style metal ones. I've also looked over the improved GM gaskets and the Napa ones. In my opinion, the Felpro metal gaskets are the way to go- no question about it. I had no issues with port alignment or sealing... the Felpro metal gaskets are really well-made from what I can tell- unlike the plastic gaskets (including the new GM ones), I'm 100% confident that these will last as long as my engine.

Flyinghigh- my guess about your leak is one of two things: Either you screwed something up when you installed the gaskets, or the leak is coming from the timing cover. I'd suggest that you clean the area very carefully, then run the car, re-checking often so that you can see where the coolant is coming from before it makes a mess and becomes less than obvious.

About dexcool- you need to read up on Dexcool if you haven't heard the horror stories. While I seriously doubt that Dexcool would cause problems within 2 weeks (and is therefore kinda irrelevent to this thread), that red stuff is BAD MEDICINE. I've seen it turn to sludge in LOTS of cooling systems, and I've worked on 3100's (with lotsa miles, to be fair) that had quite a bit of corrosion around the LIM gasket ports- and had had Dexcool in the system since day one. Now here's my biggest reason why I won't run the stuff. I worked at a Cummins dealership for several years... and Ryder put dexcool in all their trucks- this was in the mid-to-late 90's. I $hit you not- that dexcool made the head gaskets leak on every single N14 Cummins in their fleet. It also affected other engines, but particularly that one for some reason. Since then, the forumulation of the red $hit has supposedly been changed to address the problem... but why risk it? Whenever I get a vehicle with that red kool-aid in it, I immediately drain it, flush the cooling system multiple times, and refill with the good ole' reliable green(or blue) stuff.