16v rebuild

[revbond]

Alas, my 16v is beginning to burn oil at a prodigious rate. I think its time to do some engine work.

What work should be done?

The car has 140K miles. At approximately 97K miles, there was significant work done (by the prior owner) on the "top end", including new valve guides and seals, and some other stuff.

What are the chances that that work has gone bad or was incomplete or incorrect?

Should I focus just on the "bottom end" i.e., pistons, rings, etc.?

What else should I change while I'm (not me, really, but my mechanic) in there –– new oil pump? other stuff?

What should I be looking for in a complete rebuild?

All input would be welcome.

Thanks

[mbdoc]

Many of the 16V motors used excessive oil due to piston clearance. The pistons are FORGED and require twice the clearance of cast (8V) pistons, & this can cause oil consumption. Oil pump is in the front cover & doesn't go bad unless the oil never gets changed! If you need a pump then replace cover. New version has 25% more capacity. On my Racecar I use gapless rings from Sealed-power.

[revbond]

By "piston clearance", do you mean the distance between the outer piston surface and the cylinder wall? Do the rings that you use reduce the oil use? Under what conditions would I need new pistons (what would be the symptions?)

Thanks

[mbdoc]

The gap-less 2nd ring will reduce oil consumption if rings are the problem. Piston to cylinder wall is critical on this engine. Ring land clearance is critical.