Yanmar 155d clutch won't release

[scottrolfing-HT]

Ok, some background. I rebuilt the engine for this tractor.while having it split I inspected the clutch parts. Friction disc was out of spec.flywheel was beat up and needed to be turned. I bought new friction disc and pressure plate from hoye. Had a machine shop turn the flywheel. Put everything back together got tractor running good, but the clutch won't disengage. I read somewhere that there were two different pressure plates for the 155 and hoye only sells the one. The difference I think was the overall length of the unit. So I split tractor again and made a 1/4" spacer to go behind the throw out bearing. This gave me all my adjustability back but it still won't release enough to keep the tractor from moving. I adjusted the linkage till there was zero free play and it still doesn't disengage.This tells me something else is wrong.......Just don't know what. I really hate to split this damn thing again. Blah. Any input and advice would be much appreciated. Thanks

 

[winston-HT]

You did turn the clutch disc the correct way? http://www.hoyetractor.com/PROD/CD-1314.htm

 

[scottrolfing-HT]

I put it in the way that the friction disc has full spline engagement with the drive shaft.if it were flipped only 2/3 or less of the splines would be engaged. So long side to back of tractor.

 

[Norm-HT]

When you split the second time did you R&R the disc, in case it had sat around long enough to stick to the flywheel or PP from rust? Otherwise get Hoye to verify you have correct parts by #.

 

[scottrolfing-HT]

There isn't a spec of rust on flywheel disc or PP. I'll have to split it again to get numbers....Bugger. we'll see what hoye says Monday.

 

[scottrolfing-HT]

split it again this morning. went quite well actually. took the clutch and fly wheel off. i then bolted the PP on with the disc against the fly wheel and layed it flat on my drill press. used a piece of wood and the throw out bearing and carrier. i depressed the clutch fingers and the pressure plate does exactly what its supposed to do. it releases the disc. so now i'm stumped. PP is good. i have the right feel on the clutch pedal and can adjust it properly. The clutch fork pins aren't sheared.

any more ideas guys???????

 

[winston-HT]

Doubt it has anything to do with your situation but noted on Hoye's pressure plate description page some of the older models have dowel pins in the flywheel that must be removed. Just asking.

 

[scottrolfing-HT]

No dowels.

I called hoye before testing the PP and he said if the pins in the fork are good, only thing left is the pp. But now I know that it's working.

 

[winston-HT]

I'm sure they are out of the way but I was talking about dowel pins in the flywheel that must be removed on older models.

 

[Norm-HT]

Is the disc hanging up on the output shaft splines, (front to back)? Same effect as disc stuck to PP or FW by rust.

 

[scottrolfing-HT]

Put it all back together....same thing...this I held the tractor from moving and I was able to do so.I drove it around the yard a bunch.seems to be working alright. I seem to be experiencing some chatter/howling coming from transmission/rear end at certain speeds......

 

[scottrolfing-HT]

Norm, that is a definite possibility.that would explain also why I tend to have a hard time getting it into gear...and the pto spins when I have the clutch depressed.


Winston, no dowels in the flywheel except the one that holds it to the crankshaft.

 

[Norm-HT]

<QUOTE author="scottrolfing"><s>

</s>Put it all back together....same thing...this I held the tractor from moving and I was able to do so.I drove it around the yard a bunch.seems to be working alright. I seem to be experiencing some chatter/howling coming from transmission/rear end at certain speeds......<e>

/e></QUOTE>

I didn't understand any of that could you rephrase?