Head Gasket Out In A '95 3100, Any Insights?

[No Lift]

I figured I'd try the Buick sites quick before I start searching the V-6 forums. I know it is a Chevy(UGH!) but here goes anyway. My '95 Century wagon daily driver with 60,000 original miles started overheating today out of the blue. It appears to be a head gasket. Water in the oil and such. Still have to determine which one.

With all the mechanics around here somebody has to have had experience with them. Here's the question. Anybody here have any insight into replacing them or have you done it to the same engine? Just looking for some tips or if this is a usual problem with these engines. Right now the one thing it looks like is that it has non-reusable head bolts. I do have the service manual for the car so that will help.

Chevy POS. My '93 Century wagon had the 3300 Buick in it and had 140,000 miles with no problem but an accident put it out of commision. If I still had it I swear I would just swap engines.

Thanks for any help.

[gsgns4me]

Check for a bad intake gasket before you pull a head and find the gaskets are not blown. Change the o-ring on the oil pump drive cover while the intake is off (the cover will probably be a bear to get out). Don't lose (or go ahead and get replacements) pieces of the quick connect coolant pipes. The push rods are different lengths. That's not a big deal if you're watching for it and put the correct ones in the right holes before cranking the engine.

[No Lift]

Thanks for the info. I've been checking the internet and it seems the intake gasket leaking is a common occurance. Now I've got to hope driving it for a few miles hot didn't kill anything. I'm going to start teardown today.

[Carl Rychlik]

Mike,
The common thing on these engines are the intake manifold gaskets. Another thing to check for is the rear cylinder head gasket;sometimes if run long enough without the proper cooling,this cylinder head can crack. While you have the intake manifold off the engine,change the thermostat.
More than likely,my bet is it's the intake manifold gaskets causing your overheating problem.

[No Lift]

Carl,

It was frightful what I saw in there with the OEM gasket. The water passage was pushed right out. It was a chore changing the intake gasket but that was the problem. Made changing a 455 one a walk in the park. The new one I got was a FelPro "improved" version which seems to be working great. I did install a new thermostat. The pushrod tips wore badly so I installed a new set to quiet the lifters. Everythind seems to be holding together. Keeping my fingers crossed.

[Carl Rychlik]

Glad you got the job done and everything is working fine for you,Mike.