First Tractor Rebuild and Running into Major snags

Blackrubberducky · Feb 16, 2014

Recently Ive pull the 2 cylinder diesel engine from my old 1300 yanmar tractor to weld up a cracked block. It did run before I pulled the motor and ran good with plenty of power, before it sat for a couple of years. Well anyways as I was pulling off the valve cover I noticed no lifters on one cylinder, and a snaped head bolt that kept the rockers to the valves

. Could this tractor have ran on 1 cylinder for 8 years? Im extremely confused how it could even run with the amount of compression that one cylinder was making not letting gases through. Also any tricks yall have for removing the snaped head bolt

:thumbsup:

LindenBruce · Feb 16, 2014

Well, if that is a head bolt, just remove the head and you will have a stud sticking up from the block. Lock on a set of visegrips and turn the broken bolt out of the block. If it is a broken bolt that holds the rockarms arms in place, you will need a left hand twist drill bit and corresponding easy out. Center punch the broken bolt and use the drill to bore a hole into the bolt and then use the ease out to remove the broken piece. Or just take it to your machine shop and let them do it. B.

bmaverick · Feb 16, 2014

Well, on the Yanmar 3T80 engine on my retire JD850, it ran on a head cracked in two places and on 2-cylinders out of the three with a messed up fuel injection. That's how I got the tractor last year before it finally croaked. I was very surprised that the engine even ran when it did.

With that said, running on only 1-cylinder is possible. Was there more black soot out the exhaust running like that?

If you posted this in the Yanmar section, more people would have chimed in on your question.