I just had an engine put in one of my BMWs 2002. Reportedly, the lower end was rebuilt with new rings, bearings etc. All of my stuff was reinstalled, headers, Weber etc. It runs very well, very strong. But, it puffs smoke on start up. Also a little puff on gear change and throttle-off de-cel coasting, but just a little smioke. I drove behind the car coming home and was surprised buy the SMELL of the smoke. A really odd smell. It smelled a lot like the smoke out of my .45ACP and 9MM pistol surpressors that I have to pack with lithium grease. A little like beef fat burning. I'm trying to make myself believe that the smell in just some lithium grease used in the rebuild and the smoke will stop after the rings seat. I cannot detect that it has consumed any oil by looking at the dipstick, but we have only put maybe 200 miles. Ideas? thanks!
I sounds like you did not redo the head , is that true. If so you may have a valve seal or valve guide problem. With the lower end done you'll have more of a tendency to suck oil down the valve guides if they are a little worn.
I agree with the valve seals and guides being a very probable source. I've seen that many times on different types of engines. Especially Alfa 1750s and 2000s. The new rings could also be oriented incorrectly, causing seepage into the cylinder. Do you know if the walls were honed or were they "good to go"? How many miles have you driven since completion? If the rings haven't had a chance to seat properly it will smoke as you describe as well.
Maybe 200 miles max. I don't know if it was honed. I suppose I should have been less trusting.... I'm still perplexed by the really odd smell of the smoke. It doesn't smell like regular motor oil.
You said "you had an engine put in", where did you get it and do you know who rebuilt it? You also said your stuff was put on, does that include your head? The puff of smoke on start up indicates a leaky seal. Can't tell ya what the smell is, could be excessive assembly lube in the bearings, they could have put sealant on the head gasket, who knows.
My mechanic had it. He redid the bottom end because of a faulty bearing. I'll call him today! Thanks for the help.
The valve seals is probably an issue - they often go bad on these. But it is probably aggravated a great deal by the oil. The quality of the oil makes a huge difference on these engines in my experience. I had two examples of the BMW 2000 (4-door), one of them did burn a little oil but very minimal and not visible, 1:3000 or so. One day I had an oil change done at the local "Kwik Fit". Yes, my own mistake. They used Mobil Super, told me it was really good etc... but it smoked like mad and smelled horribly, too. Went back to the Valvoline Turbo 15W40 I used before the change, and voila, gone were the smoke and smell.
Did you seat the rings? Usual ring seating procedure is to accelerate the engine at medium load to abut 75% of redline then let coast down in gear. Repeat several times then do with full load. I rebuilt the bottom end of my small block Chevy after wiping a cam (new bearings) and it smoked for about 800 miles before the rings seated. Sounds like you are also burning off assembly lube. Also, after 200 miles on a rebuild, I would change the oil and cut open the filter and check it. Then run the nect oil 500-1000 miles, then change again.
Rule of thumb is smoke on start and decel is guides or seals, smoke under load or take off is rings. On decel the throttles are closed, engine is pulling air from wherever it can get it such as guides and along with that comes the oil. Engine sits, oil runs down guides as it drains back to the pan, sits in intake ports or chamber depending on if the valves are open or closed - puff on start.
Any word from your mechanic? With only ~200 miles I'd let the rings seat, if it's still smoking after 800 with a couple oil changes then I'd be concerned.
I had my daughter do the seating process. She said she can't see any more smoke. We'll see, fingers crossed.
