Autonerdz forums

James, slightly off the subject, but might talk to Tom and with a subject like this post it on the General technical area as this engine is just a boxer 4 banger much like a Subaru,  and you might get more feed back than on motorcycle forum, JMO.

Question, is this in the coolant or in the exhaust? Is there a misfire? also might look at relative compression but that might be good none the less.

As far as the fork that is pretty normal in a lot of images, my personal opinion is that is the slack at TDC, but can't prove it,  but if in the coolant I think you probably hit it.  I know the WPS 500 is a great tool here on diesels as we get misfires all the time on Internationals that may not code. Posting one here as of late which was a good test model. Actually did code with shorted to ground injector  cylinder #1 so then before we tore into it did a running test just as a good learning model. 2 JPGs one with out buffer, and one for clarity, but none the less is a great tool.

You will see that fork I think on a couple of the strikes. Also, sent A PM, might open it.

LARRY