Supercharged 3800 Series II (L67) Question

[pjstar35]

Hello all. I've been looking into buying something with a Buick 3800 engine in it so I've been doing some research and have read that the NA Series II upper intake manifold is plastic and degrades around the EGR passage and can cause coolant to dump into the engine. I'm assuming that since the Supercharged Series II (L67) has the supercharger in place of the UIM that means it doesn't have this same issue? Are there any issues with the Series II Supercharged 3800 that are unique to it? Does the supercharged engine still have the lower intake manifold gasket issues like the NA engine does?

 

[Jon Early]

Hello all. I've been looking into buying something with a Buick 3800 engine in it so I've been doing some research and have read that the NA Series II upper intake manifold is plastic and degrades around the EGR passage and can cause coolant to dump into the engine. I'm assuming that since the Supercharged Series II (L67) has the supercharger in place of the UIM that means it doesn't have this same issue? Are there any issues with the Series II Supercharged 3800 that are unique to it? Does the supercharged engine still have the lower intake manifold gasket issues like the NA engine does?

The Series 2 UIM can actually melt where the EGR "stove pipe" comes up. You won't have that issue on the L67.

There isn't any particularly unique issues with the L67 vs the L36. The LIM gaskets are still a common failure point and should be replaced if you find coolant in the oil. I wouldn't consider it a deal breaker though. 3800 LIM gaskets are pretty easy and not something you have to do regularly.

 

[87GraNasty]

You’ll want to use ACDelco aluminum intake gaskets. The failure with the original plastic gaskets is around the coolant passage gasket ends up cracking. Replace the plastic elbows with aluminum as well. Might be worth doing the water pump. Spending $30 that you don’t have to take it apart again.