Puff of smoke on engine rebuild

JJ-911 · 03-13-2006, 01:10 PM

Gday Guys
I posted this in the technical forum but dont seem to have any replies yet, Just got my car back after a complete engine rebuild and notice that when I change gears I get a puff of smoke more noticable for 1st to 2nd mechanic tells me this is common until the engine wears in, It has 160km on it since rebuild any feed back would be apreciated
Cheers
JJ

Facey · Facey's Garage

did you re-check your timing at 100km's? wait...or is it 1000km's....damn been 4 years since i did the break in procedure....

someone here should know this....someone here is also doign a break in.....if not, and either way, the answer to your quesition is yes it is common, no it isn't always good, and yes it should eb an easy fix.

when a rebuild is finished the pistons rings aren't seated, therefor oil seeks through, and get burned, making smoke, i assumign you are accelerating while switching from 1st to 2nd, and therefore piston speed is high,

but at some point once everythign begins to seat you need to have your timing coudble checked (possibly re-set)....

cheers
Nick

JJ-911 · 03-15-2006, 03:40 PM

anyone olse with some feedback

beepbeep · 03-17-2006, 09:07 AM

Yes, engine usually smokes for a while after a rebuild. It's due to residual oil burning up and oil-seepage past unseated piston rings.

Rings usually seat quite quickly (<500km) and opinions on how to make them seat the best possible way usually vary depending on whom you ask.

My personal opinion is that freshly rebuilt engine should be broken-in using good mineral oil, lot's of varying revs, lots of engine braking but w/o using full throttle. After 500km, engine should be considered broken-in and oil/filter should be changed to preffered brand. I personally prefer fully synthetic.

If engine continues to smoke on shifts even after 500km I would consider taking it back to shop for a check.