Satoh 630D Bull Clutch Stuck

[Ehanson]

OK, These forums are great! I have just learned a few things by scrolling though this thread. First off, my clutch on my Satoh-Mitsibishi S373-D seized "on" after sitting a couple weeks. I tried to break it free by running the tractor around, but to no avail. Tucked it into the shop and started to split it in half. Got it apart and really do not find anything failed. I did find a lot of rust and the bellhousing had moisture droplets in it. The pressure plate and flywheel surface had a hard rusty scale on it. The clutch friction disc has enough wear to have a complete smooth surface, no flutes remaining. So, I find this thread and it talks about frozen clutches! Wow! And while taking the tractor apart, I came across this ell shaped bar, after reading above, I think it is to hold the clutch pedal depressed! I won't know for sure until I get it back together.
I can't believe the friction disc stuck itself to the flywheel or pressure plate.
If I take the Steering column off the tractor, can I see the throw out bearing yoke? Maybe a pair of needle nose pliers can reach the fork and see if is has broken free of the cross shaft.

 

[motomedic]

Yep you can look right at the clutch and throwout bearing if you pull the steering box

 

[FritzM]

I am having issues with my Satoh 630-D Bull clutch. The tractor has ran just fine since I've owned it the past year until this last week. It appears the clutch is "stuck" enaged to the flywheel. It only sat a few weeks between use so I find it hard to believe it rusted to the flywheel, but may have happened. It has sat longer several times until this last time, but maybe the moisture level was just right. I've tried all the tricks to jar it loose with no success. I've tried dragging implements, skidding tires with clutch pedal depressed etc. I'm running out of ideas before I split the tractor and see what's going on. I've even disconnected the clutch linkage and manually tried to force the clutch arm further than the linkage does in normal use to put more pressure on the pressure plate, no success.

Has anyone else had similar issues that wasn't a result of a rusted clutch? I'm a fairly experienced mechanical guy, but could be overlooking something. It just seems odd that it would rust that bad in just a couple of weeks. When I start it in gear and drive it, it works fine, I just can't switch gears, or engage gears while its running, it must be shifted while not running, then started in gear to move it.

I'm open to suggestions before I split it. Thanks.

Our tractor was like that when we got it, the clutch is probably the same on yours as it is on our ST-1300. The clutch slides on a rod & it rusts on to the rod & won't slide. if you can get to that rod with some PB Blaster it should free up. I don't think we had to break it in half. It was several years ago. FritzM