I'm working on a 2002 b2300. It's got misfires on cylinder 2 and 3 and very sluggish to rev. The compression seems way too high at 240 psi per hole. I thought maybe the cats were clogged but I removed the upstream o2 ans the compression and symptoms are the same. Does this compression seem high for a 250k engine? I thought they should be around 180. So now I'm thinking it could have jumped time on the exhaust cam but I'm not sure how too check without pulling the intake off. The timing chain doesn't rattle so I wouldn't think it would have slipped but what do yall think?

 

There is a plug down low on the left side of the block. You remove it and insert a threaded rod turn the crank manually until it stops. That is top dead center. And yes you have to remove the intake, because the the valve cover has to come off. Then there is a cam tool it is basically a piece of flat steel the fits into slots on the back of the cams. So if the steel won’t slip into the slots then yes the timing is off. Note there is no key way in the crank and the lower timing gear is held place by friction. So yes the timing could be off because of the crank gear slipping on the crank. The tools to do this are sold as a set and are not very expensive.