I just replaced the head gasket on a 2000 Volvo S80 2.9l that was driven overheated until the engine stopped (stalled or seized, I wasn't there). Engine overheated because a radiator hose slipped off. When it gets up to temperature, I'm still getting white smoke out of the exhaust (though, not nearly much as before the gasket replacement). Other than white smoke coming out of the exhaust, the car seems to run and sound fine.
Took the head to a machine shop to have it milled and checked for cracks. They milled off .020 inches and said they checked for cracks and found none. (I have never used this machine shop before, and don't know anyone who has used them. It is just the only automotive machine shop in the area. They did seem careless by just throwing head up on the counter on the freshly milled surface.)
I checked the block deck by setting a Harbor Freight square on it, and trying to slide a feeler gauge of the specified tolerance under it. Seemed good, but I've never done this kind of stuff before.
I torqued everything to the specifications, of course.
I only visually inspected the cylinder walls with the second piston at TDC. I'm not equipped to pull an engine, so I figured I'm screwed if anything in the bottom end is messed up anyway. Didn't see any cracks. Not sure what else to look for.
The engine is aluminum with sleeved cylinders.
I can only think of these causes of antifreeze burning:
- Improper head gasket installation.
- Possible I guess, but I torqued everything to specifications, and followed a factory service manual.
- Cracked head.
- Had an automotive machine shop check it for cracks. Not really sure how they did that, or if they were thorough.
- Warped block
deck.
- I checked for warpage in a very non professional manner. Seemed OK.
- Cracked block and sleeve.
- This is the only way I can think of for antifreeze to enter a cylinder from the block. But, is this very likely to happen? Sleeves are very strong, and the sleeve would have to crack in the same place as a crack in the block adjacent to a water jacket, correct?
Any other possible causes of steam coming out of the exhuast? What causes are the most likely?