Coolant Leakage

[btay801]

I have a 3800 series II with the supercharger on it and am having problems with coolant leakage around the intake gasket. This appears to be a big problem on the 3800's. Even several lawsuits against Dex-Cool for it compromising the gasket seals. Other than that great engine. Does make a strange "ticking" noise too. Might be the lifters.

[tblake]

It is going to be a major swap. You will need to swap the motor, trans, maybe subframe, wiring harness, pcm, fab fuel lines, coolant lines, and probably AC lines. Not to mention the wiring you are going to have to figure out what wires do what and make lots of splices.

btay801, the 3800 and all GM V block motors have issues with Lower Intake Gaskets leaking. GM is laying the blame on dex cool as the fault for the blown gaskets. However the real issue is in fact the horrible shoddy design of GM gaskets. Seems as though the are actually made to blow. See this thread...

http://www.automotiveforums.com/vbul...d.php?t=958284

[btay801]

WOW! That is disgusting if it is the truth! I have searched this site for many hours and never say that thread. After I cleaned off the Dex-Cool and blew it dry with shop air I could actually see the coolant pushing just above the seal and below the intake! What are the best gaskets to run and what other mods can I do while in there. I have a 2001 GTP and want to put a smaller pulley on it eventually. I saw a video on youtube and the guy was saying to plug the coolant ports on the S/C and open up the throat of the "V" on the S/C outlet. Ever heard of any of that?

[BNaylor]

These posts have been moved to its own thread retitled "Coolant Leakage". Please try to keep the issue and content related to the thread posted in or on topic. Or simply start a new post with your issue.

[tblake]

I went with the GM Metal Framed Gaskets although they do have their own issues like oil leaks where the LIM mates with the block.

Fel-Pro brand LIM gaskets are probably your best bet. And even though they are plastic, they don't have those damn little slits in the coolant passages.

As far as Mods go, I just went ahead and installed a ported Lower intake manifold. It saved me from having to clean all that old gasket material off the old LIM. I just washed it off and shipped it back as a core. The ported one was about 200 shipped but I got 75 back for shipping back the core. When you order you can specify if you want the coolant passages to your throttle body blocked off. Since you live in a warmer climate, you could give it a shot. I had to leave the coolant flow through mine to keep the throttle plate from freezing open during the winter.

[tblake]

And BTW, that ticking of the lifters, usually that is a tell-tale sign that there is coolant contamination in your oil. While you are in there replacing your LIM gaskets, it may not be a bad idea to replace the lifters.

[btay801]

Thanks for the info. What brand intake did you buy? And what would be a good intake manifold that would support a smaller S?C pulley?

The "ticking" noise is very pronounced at cold start up then goes away after it is warm. Does this still sound like lifters?

[tblake]

See signature.

Ticking definatly sounds like it could be the lifters.

[btay801]

I now have an intake on order from Milzy Motor Sports. Where is a good place to get the lifters and how difficult to change them out? And who can I coult on locally to carry Fel-Pro gaskets? Auto Zone? Napa?

[btay801]

"Since you live in a warmer climate, you could give it a shot. I had to leave the coolant flow through mine to keep the throttle plate from freezing open during the winter."

It gets kinda frigid here too is Salt Lake. Usually never below 5 degrees Fahrenheit. And she is garaged. Can I still plug the jacket that goes around the S/C?

Thanks for all the useful information. You don't know how much I appreciate it!

[tblake]

I don't want to say either way on plugging the coolant passages. Someone else with more knowledge could answer that for you.

Fel-pro gaskets are usually available at most auto parts places.

The lifters could be quite expensive to replace all 12. Plus if you do want to replace lifters, you will also need to replace the valve cover gaskets while you are in there.

[btay801]

Well I finally am getting around to replacing my LIM due to coolant seepage that collects on the intake manifold indentations. As you can probably tell, it has been leaking slowly for a few months.

My concern is that I thought when I pulled the manifold I would see the deformed seals around the "V slits". As you can see from the pics, no bulging or deformation. Why are they leaking then?

Second, I will replace the o-ring from the water pump to the intake manifold. But is there another replaceable seal on the water pump side of the plastic elbow? Or do I just have to replace the whole water pump assembly?

Thanks in advance!

[tblake]

Bottom right coolant passage for the leak.

What year is your car? On 99+ 3800's there are two replacable coolant elbows. 98 and 97 you will have one replacable plastic elbow, and one o-ring on the other elbow. Be carefull, they tend to break off, so bofore you put it back together, make sure you dig all the pieces out.

[richtazz]

Agreed with Tim's observation. The bottom intake gasket in your pic has failed both at the coolant passage and intake runner passage on the right side. This was definitely where your coolant was going.

[tblake]

Looks like he is even missing a chunk of the little plastic intake runner. I wonder where that is stuck in his system right now?...