# case 3688



## nicks55 (Feb 8, 2007)

Need some advise. I have a case/int'l 3688. I've been running a a 15ft.shredder behind it for several days with no problem. Yesterday,the blades started running slow and wouldn't cut. I checked the hydraulic fluid and refilled it. At first the blades turned normal but once back in the fieild the blades turned slow. I know the problem is with the tractor,not the shredder. I have run the shredder before for yrs. and never had this problem. Does anyone know what could be causing this. 
Nick


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## Live Oak (Dec 22, 2003)

Nick,

I am thinking an o-ring or other packing is leaking or is blow somewhere is the pto engagement circuit (clutch pack). Does the pto loose rpm like this in both the 540 and 1000 rpm shafts?


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## wass (Jan 3, 2007)

I'm guessing it has a clutch in the PTO shaft. Are you sure it isn't slipping? Thats happened to me a few times. If so, I tighten the springs to specs ( or a little tighter ) and it's off to the races again.


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## HYDROGUARDIAN16 (Feb 14, 2007)

sounds like u figured it out?


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## nicks55 (Feb 8, 2007)

Thanks for the replies......I just ordered a service manual for that tractor. Do you know where the service clutch for the PTO is located on that tractor??? I think soemthing just came loose.
Nick


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## urednecku (Aug 29, 2007)

I'm thinking wass is talking about a clutch on the shredder, not the tractor. But then again, I'm not a mechanic.


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## Live Oak (Dec 22, 2003)

I was thinking the same thing too at first but I was thinking the 15 ft. cutter is a batwing type and most of these types of cutters I have seen have separate slip clutch for each cutter gearbox on the cutter. Usually if the slip clutch is giving way, you will see a good bit of smoke. Definitely a good point and well worth looking at.


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## nicks55 (Feb 8, 2007)

*case 3688 reply*

Just hooked up the PTO on our Case 3688 to a 1000rpm hay cutter and nothing...It didn't turn at all. If its a blown O-ring,can it be easily fixed or do I need to take it into the shop.? Further, does the O-ring sit right behind the plate that goes over the PTO???


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## Live Oak (Dec 22, 2003)

I am not sure on your tractor but I would imagine that it may well entail tearing deep into the transmission area. I would suggest you call your local shop and ask them what they think and a rough estimate. The 3688 is no small farm tractor and I am sure will require some major heavy lifting equipment and special tools.


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