2001 Yamaha 1200 XLT Engine Problems

[kylelbc]

I rebuilt my engine a year ago because I flooded it with salt water. Installed a rebuilt crank, new rings, new plugs and rebuilt the carbs. My family took it on a trip and said that the engine temp alarm started going off after a few minutes of use. I'm guessing this started after the first tank of gas that had break in oil mixed in. The #3 piston is fried and cylinder is scored. I pulled the oil line off that carb and cranked the engine and got oil through the line.

I plan on rebuilding that cylinder but am confused why it did not get enough lubrication even though oil is getting to that carb.

Any ideas?

Do I need to tear the whole engine apart to clean the crankshaft and case? There are no visible pieces from the rings although I get a grey metallic substance on my finger when I swiped the crank case with my finger.

[Technical Support]

Re: 2001 Yamaha 1200 XLT Engine Problems

The cat maybe clogged causing heat build up or the rear seal maybe blowing out, this would cause the lean condition your having

[kylelbc]

Re: 2001 Yamaha 1200 XLT Engine Problems

I had already pulled the head and bad cylinder before finding out about pressure testing. I reassembled the engine and pressure tested it. There is a leak at the rear seal where it meets the crankshaft. Is this my smoking gun or could that leak have been caused by the engine running hot for another reason?

Is the seal sold by SBT OEM from Yamaha?

[Technical Support]

Re: 2001 Yamaha 1200 XLT Engine Problems

Yes this could be the issue, SBT makes a better seal then the factory seal, ours is re-inforced with a steel ring in the rubber flange to prevent it from blowing out, something yamaha should have done years ago.

[kylelbc]

Re: 2001 Yamaha 1200 XLT Engine Problems

Okay so I think my plan of attack is to tear the engine down to thoroughly clean the bottom end. Rebuild it with a replacement cylinder, piston, rings, etc. and new seals.

Any recommendations on where to buy the cylinder and piston? Would buying a good used cylinder be okay or not?

[Technical Support]

Re: 2001 Yamaha 1200 XLT Engine Problems

We may have single nicasil cylinders, give us a call