problems junk 365s 371, 372

[rupedoggy]

Had a pile of trash saw parts from a dealer junk yard. Looked like enough to put a saw together. First attempt was a 371 case and crank with a top end from a double intake cylinder and matching piston. Would not turn when assembled. So took the top and put it onto another 365 and it ran but made a bad noise. The bearing on the side were junk and the balls just floating around. So I got another half case that said 372 and matched it up with a case that looked good. Now it will not turn when the piston and cylinder is put on. I know I have some old and some new parts but I put together lots of 372s before they had the piston and cylinders with the "extra" ports. I guess the two different saws are not compatible. Did anyone else try this? Any hints? BTW the piston is not "sticking" at TDC but looks like more or less at the bottom.

 

[huskihl]

Double intake xtorq cylinders have an extension that doesn’t fit into pre-xtorq cases

 

[Gord404]

Double intake xtorq cylinders have an extension that doesn’t fit into pre-xtorq cases

ya by trying to bolt one on you might have narroued the bottom of the cylinder creating a tight spot because it would squeeze the cylinder in at the bottom

 

[rupedoggy]

I think the protruding portion at the bottom of these late style cylinders is hitting the crankshaft ever so slightly.

 

[huskihl]

I think the protruding portion at the bottom of these late style cylinders is hitting the crankshaft ever so slightly.

I don’t think it’s hitting the crank, at least it wasn’t before you bolted it down. If you look at the difference in the cut out in the top of the cases you’ll see what I’m talking about. The original models only had about a 1/4” deep cut out for the extension. The xtorq models have about a 3/8” deep cut out

 

[rupedoggy]

Good point my man and I think I have it solved. The old model case has a lip just at the bottom of the area where the extension fits. A small lip to be sure but interferes none the less. If you bolt down the cylinder with this lip it will squeeze the extension in just a little and make the piston difficult or impossible to turn because it is hitting. I found the interference spots are in three places and ground a little off the extension to clear Voila! here is a picture with three ground spots. Maybe a little hard to see but it worked!

 

[huskihl]

That is a 365 cylinder. You can see the dividers in the transfer caps. If you’d like to make it a 372, you can remove those caps from each side and grind out the divider. That is the only difference between a 365 and 372 xtorq engine

 

[rupedoggy]

Good to know. I am learning still at 77