I have a 2003 6mt coupe that consumes a quart of oil about every 700 miles and has a knocking sound on cold starts. Its been this way for almost a year now but once everything is warmed up it seems to run fine. Either way i have decided to build another engine for it starting from a new engine block and slowly building it up. I have researched oil consumption and found many different possible causes and possible solutions. It always seems to be different from case to case. One potential cause was bad piston rings so new Wiseco pistons and rings will cover that. Another says leaking valves are the cause so I will be buying new valve sets, Z1 viton valve stem seals and new bronze valve guides. I've also heard the precat as one potential cause so ill be doing away with that too. And while I'm at it i will toss on a oil catch can for ***** and giggles. This should cover me if in fact any of these are the real cause. I realize it would be alot easier, and cheaper, just going and buying a new short block or low mile complete motor but this will also be a learning exercise for me since I have never built a motor from the block up before, just replaced short blocks. I was wondering if there was anything else that i can make sure and cover while im building my engine in regards to preventing oil consumption from happening again. Thanks everyone and I apologize in advance in spamming the boards for a while with my questions and progress.

 

The cause of OC according to everyone I've talked to at several Nissan shops is their poor quality piston rings. You're covered there, "Good Luck & enjoy the build!"
Gary

 

Hey let me know how that goes, I'm looking at doing a rebuild myself just trying to find a shop in California.

 

PrecisionZ in Canoga Park is where I plan getting all my machine work done and anything else I'm unable to do myself. Unfortunately my car was recently side swiped in a parking lot so i have to wait for insurance to get it fixed before I'm able to continue my engine build

 

Sorry to hear about your car. Do they do aftermarket work because there website looks more like a stock shop?