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What is wrong with my MT250?
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Author:  snhuklm [ Tue May 12, 2009 1:04 pm ]
Post subject:  What is wrong with my MT250?
I just got it running this weekend, but it smokes (white smoke). I noticed oil spitting out from the head and into the exhaust pipe.

I've read about jetting(?), timing and possibly crankcase seals being the culprit. I want to make certain the issue before I tear into the engine which is something I've never done before.

Any help would be greatly appreciated.

I've come so far...I'm almost there!!!

Kyle
Author:  dogger315 [ Tue May 12, 2009 3:33 pm ]
Post subject:  Re: What is wrong with my MT250?
White smoke sounds like timing. The excess oil may
be a by-product of incomplete combustion.

Ray, since this an MT, you want to jump in here?

dogger
Author:  rayivers [ Wed May 13, 2009 8:51 am ]
Post subject:  Re: What is wrong with my MT250?
Kyle,

This is from a post you made on May 9th:

Quote:
I took the exhaust off and oil was dripping all over the place.

This sounds like a lot of oil. Several things spring to mind:

1) oil pump cable way out of adjustment
2) incorrect oil in injector tank
3) bad clutch-side crank seal
4) leaking center case gasket

My buddy's MT250 still smokes a bit (bluish-white smoke), probably due to some misadjustment of the pump cable. At first fire-up after 15+ years idle it smoked a lot, but I was running 40:1 premix until I verifed the oil pump still worked.

Below is the oil pump diagram; figure 69 shows the adjustment marks.

Ray
Attachment:
MT250 Oil Pump.gif
MT250 Oil Pump.gif [ 128.99 KiB | Viewed 5312 times ]
Author:  woosh [ Wed May 13, 2009 11:18 am ]
Post subject:  Re: What is wrong with my MT250?
I found out it was my clutch side crank seal by leaning the bike way over on the kick stand side and that alloweed the crank oil to run to the other side of the crank and the seal started to suck air in and leaned way out and the revs picked up once that happened I knew right what it was I had thought it was jetting the whole time and am lucky I didnt burn up the top end. I did this on accident but it worked to find the problem. I have no oil pump on my bike I took it off so I knew that wasnt the problem.
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