Sitting motor likely to need work?

Posted: Thu Nov 03, 2016 3:08 am

Hello, I have a motor that has been sitting in a dry, heated, interior closet for about ten years. It was a runner when removed from its frame and as I recall it had 30kish miles on it. As far as I know, the motor was not treated for storage and has just been sitting there with the carb intakes and exhaust openings exposed.

I know this can't be answered definitively but how likely is that the motor will still be good to go? I'm worried about seals, valve guides etc. I'm thinking about mounting this motor while I try to rebuild the bikes original motor. Thanks in advance for your thoughts.

Posted: Thu Nov 03, 2016 8:10 am

Look for dirt in the open holes. Get it running and hot and then change the oil shortly after (use junk oil). I'd turn it over a few times in the CORRECT DIRECTION first.

Should be fine. I've done car engines that sat for years to have them for many years more.

Most issues come with storage in a humid place or non-temp controlled.

Posted: Thu Nov 03, 2016 4:49 pm

what he said, but before I would remove the plugs, shout some WD-40 down the plug holes and turn it over by hand a few times

Posted: Thu Nov 03, 2016 5:15 pm

additional things I do for an engine that's been sitting - you've got it off the bike so best do things before fitting
there is one cylinder sitting open, have a good look with a decent torch - if there's corrosion etc.. it will likely be this one you'll see a partial valve seat / face - is it clean ?
before rotating - cam cover off and a good engine oil lub around the valve buckets / cams etc..
after wetting the bores with WD40 ( overnight soak) and a few gentle hand rotations
with the engine oiled up plugs out - loosen the oil banjo at the cylinder head and start cranking with a fresh battery jumped to the starter motor - short bursts ( don't cook the starter) until you get fresh oil at the banjo - nip it up and a few more spins to wet the head

before doing all this - it can be a good idea to gauge the valve clearances - then check again after a good spin up - there shouldn't be any difference - if there is then you may have some carbon or crud in a valve seat - most likely the cylinder that was open - at least you know

Posted: Thu Nov 03, 2016 8:51 pm

Yeah, I should have mentioned a slight bit of something to relube what may be dry cylinder walls.............also just before start, kill the kill switch and rotate with a strong battery to prime the oil system, with any luck the light should go out saying you at least have 5 psi or so to then have pressure light go out quick at start.

If you yank top cover for valves then you can refill the cavities around cam lobes with oil so lobes start up good and wet, they will be empty if motor moved about out of level.