Grader pony locations

The last of the graders with the original D318 and the horizontal opposed pony motor were oil clutch designs. However the oil is shared with the engine, not separate like the tractors.

8T16361-up were oil clutch from 1955-57 and could be either pony or direct start. The next series 70D pony start, produced from 57-60 were the last of the #12 models with the D318 and the H.O pony

80C is direct start, oil clutch D318 equipped, beginning in 1955 produced concurrent with the last of the 8T pony start graders. This was the last series of the C graders.

70D pony start oil clutch graders started at the end of 8T production in 1957. The 80C series ended in 57 and 71D direct start began production in 1958 and continued through 59 while the pony start 70D continued into 1960.

The 99E with D333 engine and a similar shared-oil clutch began in 1959.

The shared oil design really doesn't seem to cause a lot of problem, though logically it would have to be detrimental to engine life. Sure would want to stay on top of oil and filter changes!

We resurrected a 99E that had had a piston seize and come apart from lack of lubrication. The root cause of failure was the oil pump sucked up a sheetmetal bolt locking tab and locked up, shearing the key on the drive gear. The sheetmetal tab must have been left inside the oil pump suction bell during a previous overhaul. The screen over the suction was intact and there is no place where a locking tab is used inside the suction bell, so it had to have been an oversight that it was left in there. It ran some years before failure, so I guess it was simply bad luck that it finally moved up into the pump.

All that to say that the failure of that engine had little to do with the shared-oil clutch design!

[quote="ccjersey"]80C is direct start, oil clutch D318 equipped, beginning in 1955 produced concurrent with the last of the 8T pony start graders. This was the last series of the C graders.

70D pony start oil clutch graders started at the end of 8T production in 1957. The 80C series ended in 57 and 71D direct start began production in 1958 and continued through 59 while the pony start 70D continued into 1960.

The 99E with D333 engine and a similar shared-oil clutch began in 1959.

The shared oil design really doesn't seem to cause a lot of problem, though logically it would have to be detrimental to engine life. Sure would want to stay on top of oil and filter changes!

We resurrected a 99E that had had a piston seize and come apart from lack of lubrication. The root cause of failure was the oil pump sucked up a sheetmetal bolt locking tab and locked up, shearing the key on the drive gear. The sheetmetal tab must have been left inside the oil pump suction bell during a previous overhaul. The screen over the suction was intact and there is no place where a locking tab is used inside the suction bell, so it had to have been an oversight that it was left in there. It ran some years before failure, so I guess it was simply bad luck that it finally moved up into the pump.

All that to say that the failure of that engine had little to do with the shared-oil clutch design![/quote]

Thanks for the info. I'm hoping it is a 70d should be a good ranch grader. My understanding is that the oil clutch is pretty much matenance free.