[mauroguti24]

So I bought a e90 335xi that was sitting for 12 years. Unfortunately car was imported from Germany and the owner never went through with the paper work transfer. I decided to do a n54 e91 build. I was able to get the e90 running after getting a new battery and adding new fluids. Everything sounded and looked good prior to remove engine.

Currently have both engines out the n52 and n54. The swap seems to be pretty straight forward. The first mods I will be doing downpipes, charge pipe, and jb4.

My main question is what gaskets and o rings should I change, or parts. Mainly concerned with turbo gaskets and o-rings. I assume that 12 years of sitting there are parts that need changing and maintence that should be done. Just need help from you more expierianced bmw owners.

[Emilime75]

I know many would disagree, but I'd err on the side of caution and would replace as much as possible while the engine was out. Every o-ring, seal, gasket, hose, belt...anything that tends to deteriorate just from age, i.e. rubber.

I'd imagine plastic hose fittings "should" be ok, but might be worth thinking about.

[CTinline-six]

Originally Posted by Emilime75

I know many would disagree, but I'd err on the side of caution and would replace as much as possible while the engine was out. Every o-ring, seal, gasket, hose, belt...anything that tends to deteriorate just from age, i.e. rubber.

I'd imagine plastic hose fittings "should" be ok, but might be worth thinking about.

I would agree. Total cake doing in on an engine stand all at once vs. down the road when it's back in the car.

[IllSic_Design]

I'd do anything and everything that you can afford. Oil pan gasket, valve cover gasket, possibly rear main seal if it looks like it is leaking(probably is), oil filter housing gaskets, etc.. as said above

[E7J3F3]

Anything that isn't solid metal is suspect. Gaskets, hoses, fluids, etc. I'd change the motor/trans mounts, rear main seal, oil pan gasket, waterpump, and the big coolant hoses while everything's apart. Basically just do all the horrible jobs at once and keep an eye on the rest.

[tcphoto]

I imagine you’d have the easiest oil pan gasket and rear main seal ever. Yes to the VCG and OFHG also.

[mauroguti24]

Thanks for all feedback I have been busy plugging away little by little. Taking all of your tips so far stating from bottom end up. Still need to do rear main and the hoses.