Thread: Coolant disappearing

LIM gaskets maybe? A small amount of coolant over time won't be visible, but it will add up.

If the leak persists, it will clog the coolant passages. That and Dex-cool make for a lethal combo. If enough gets into your oil, it'll be lights out.

This isn't a 3800, but you get the picture.

your thermostat may be shot, try changing it. also flush your coolant and bleed the system with the brass screw on top of the t-stat housing.

and the water pump will not just quit working unless its seized, or on its way to being seized, and then it would squeal like a pig. when they go bad they leak from the under the snout behind the pulley, there's a weep hole that it leaks from. at first it leaks a little, and as you let it go they leak a lot, enough to lose coolant and then over heat.

Originally Posted by thumbs

Sorry but tha lim is from a 60 degree v6 3100-3400 model not the same engine at all. The most common leak on the 90 degree 3800 is the uim gasket. The reason being is the egr pipe goes thru the lim and into the plastic uim. They sarround this pipe with coolant to keep it cool but over time degrades the gasket. The other thing you can check is to see ifd the head gaskets are leaking compression gas into coolant system pressurizing coolant system blowing coolant all over from the overflow bottle.

Wut.

No guy.

Head gaskets NEVER go bad on these cars unless your running a trillion psi of boost.

The UIM's go bad because they get hot...but the coolant issue is in the LIM...where the dexsludge eats the factory plastic gaskets. That is why you get the Aluminum replacements. It has nothing to do with the EGR...either.

I posted those pics to display an example of what coolant mixed with oil looks like.
The LIM gaskets between the Lower Intake Manifold and the Heads on a Series II 3800 like to leak after a while and they will cause similar damage and buildup.

Originally Posted by thumbs

Sorry but tha lim is from a 60 degree v6 3100-3400 model not the same engine at all. The most common leak on the 90 degree 3800 is the uim gasket. The reason being is the egr pipe goes thru the lim and into the plastic uim. They sarround this pipe with coolant to keep it cool but over time degrades the gasket. The other thing you can check is to see ifd the head gaskets are leaking compression gas into coolant system pressurizing coolant system blowing coolant all over from the overflow bottle.

NOOB FAIL! NOOB FAIL!

Originally Posted by matt5112

EGR warps UIM on the L36's...

But i'm just a nub

But who has EGR's?

Newbz

Originally Posted by MyPrixGT06

I'm having the same problem. How do I check if the LIM gasket is back?

my guess is you meant How do I check if the lim is BAD?

if thats what you asked, you can have the system pressure tested to see if it holds pressure, or buy a tester. like this Mityvac MV4560 Radiator/Cooling System and Pressure Test Kit