1988 JD 750 Clutch Question

[Evets Tsorf]

Thanks beenthere, worth a $12.50 gamble, this is the shift knob, if mine had an embossed pattern on it is long gone. I will be hopeful the new one has it, if not it will be the shiniest part of the tractor. Will be stocking up on Rustoleum green and yellow aerosol as well.

 

[beenthere]

Use genuine JD green and yellow.. those substitute paints will turn blue after a year or so. But that is your decision..

 

[Evets Tsorf]

Have seen some blue tractors on Craigslist, thought they where Ford, Mitsubishi or New Hollands, do you think they where just John Deere's with lousy old paint?
I will use the Rustoleum spray just to protect some rusty areas, someday I will have it looking like a grand piano, right now I am trying to keep it from looking like an old outhouse.

 

[Evets Tsorf]

Received new knob from JD, $24, pattern is on it, not your typical H:

4-8 3-7 1-3
-- N --
2-6 R

 

[beenthere]

Received new knob from JD, $24, pattern is on it, not your typical H:

4-8 3-7 1-3
-- N --
2-6 R

maybe an extra 3, and the one on the far right is instead 1-5 ??

 

[Evets Tsorf]

Correct, but a pair of three's would be a better hand.
4-8 3-7 1-5

N


2-6 R

 

[Evets Tsorf]

Still trying to resolve my dragging clutch issue. Just realized there is access to this area without splitting tractor. The steering box is bolted onto transmission case just above and slightly aft of throw out bearing area. If removed I can at least see the throw out bearing fork and shaft and make sure it is not worn or damaged. An elongated pin hole in this area would reduce throw out bearing travel.

 

[Evets Tsorf]

Week before last I pulled the starter with the hope of getting a light and mirror past flywheel to view throw out linkage. No joy, clearance to tight. May be able to slip borescope through but, starting to resign myself to splitting tractor and changing clutch components. As noted there is access to area through steering box attach area. To access this requires disassembly of instrument pod, fuel tank and steering box, all things that need to come off to split tractor. Obviously I will look for obvious issues through steering box area but am now planning the split as a winter project.

This prompted by conversations with a couple tractor tech’s that suggest a fairly common issue is the diaphragm in the pressure plate may have been overheated, this can take the temper out of diaphragm and it flexes and can thus decrease effective travel to release pressure on clutch plate. The 3/4 inch free play on linkage assumes all components in clutch system working properly.
I will use the tractor gently until the split to reduce transmission damage, clutches are cheap and require some labor. A transmission is less available and more costly.

 

[beenthere]

I will use the tractor gently until the split to reduce transmission damage

To avoid grinding gears, maybe put in desired gear before starting engine.
Assume the gear grinding is one of the annoying problems associated with the dragging clutch.

 

[Evets Tsorf]

Beenthere,

Engine will not start unless in neutral, I could disconnect the switch. For now I keep the RPM as low as possible and put it in gear right after start before gear train gets spooled up. Going from gear to gear is no issue if done quickly but if left in neutral with engine running you must crash it into gear.