Consuming oil

[CR325IS]

My car has had this engine from bav auto recyling for some time now close to 3 years.( I blew my old one due to oil pump failing) That was before I found R3vd to help me find a new engine or possibly one someone built. But thats besides the fact, the engine I got was suppossively compression tested and everything checked out. (I don't think that was the case). Well my issues are it uses a lot of oil between changes. When I drive home on long trips about 420miles I have to stop and put in close to a qt of oil in it. There are no leaks anywhere, no oil in coolant, no black smoke, and my mechanic took a look and couldn't find any sign of any leaks that would cause me to lose that much oil. Even in town I have to keep oil on stand by because it will use half a qt every couple of weeks. I am not fouling plugs and cannot figure out where to look or test or what the issue might be. I was possibly looking to rebuild but if thats not necessary I don't want to go that route. But if it's the piston rings...which I have heard it may be..I would just buy new Maxsil pistons instead. Any help/ suggestions would greatly help. This issue is driving me nuts!

[MR 325]

What type and weight of oil are you using?

[CR325IS]

I have used shell 15w 40 and Pennzoil 20w50. Both the same result.

[jlevie]

Have a shop run dry and wet compression tests and a leakdown test. That will tell a lot about the condition of the engine.

[CR325IS]

ok is there anything specific I should mention besides what I already did above?

[jeffnhiscars]

worn valve guide seals are also a potential source of oil consumption..and a lot cheaper to repair.