I have an '81 XS650 street tracker, stock engine as far as I know. I got it a couple if years ago as a project in progress so don't know how many miles it had on it but I've put on13,600+ miles since. At the beginning of my time with it I cut off the stock mufflers and replaced them with a pair of nearly new stock Sportster mufflers that somebody took off when they got aftermarket cans. At the time I wondered at the restrictive-looking honeycomb just inside the inlet but they seemed to work and sounded good to me. A few months ago I began a commute home and it started running rough, apparently on one cylinder. The entry section of the left muffler got so hot it turned blue, so figuring it was blocked somehow I pulled it off. It seemed to run better and I thought I might get home with one open pipe, but a few miles later oil started spraying out under the left cylinder outlet.
You probably already figured out that the Sportster muffler has a catalytic converter in it...if I'd had half a brain I'd have knocked it out to begin with but I don't and didn't. I assume that my old motor finally put more rich exhaust or oil or both in than the cat could stand and it melted down and clogged.
So, I figure I overheated the left cylinder enough that the head distorted and let the oil out. It's taken me until now to get the motor out and take off the head. The head gasket is stuck to the top of the cylinders and did not look damaged. There was oil all over the top of the gasket and it seems clear that the oil escaped between the head and gasket.
Any suggestions for how to verify whether the head is warped or not?If it is, what next?
Thanks,
John
You probably already figured out that the Sportster muffler has a catalytic converter in it...if I'd had half a brain I'd have knocked it out to begin with but I don't and didn't. I assume that my old motor finally put more rich exhaust or oil or both in than the cat could stand and it melted down and clogged.
So, I figure I overheated the left cylinder enough that the head distorted and let the oil out. It's taken me until now to get the motor out and take off the head. The head gasket is stuck to the top of the cylinders and did not look damaged. There was oil all over the top of the gasket and it seems clear that the oil escaped between the head and gasket.
Any suggestions for how to verify whether the head is warped or not?If it is, what next?
Thanks,
John
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