what's the proper oil for the pony clutch? the book says crankcase oil but I vaguely recall on the site a recommendation for transmission oil or transmission fluid if the clutch tends to pop out. If the latter, would that be something like Dexron used in cars?

The transmission fluid recommendation is for those pony clutches that are very hard to brake when engaging the pinion gear into the flywheel.

The pinion clutch brake is essentially not adjustable although there is a procedure to cup the disks in the clutch by bending them. So it requires disassembly of the clutch to stop it grinding.

You can easily drain the pinion oil and replace it with Dexron or a TO rated fluid in a few minutes and my experience is that it’s immediately easy to stop the pinion grinding when shifting it. I’m a believer in the technique.

Adjusting the pinion latch springs and or replacing worn parts can stop the pinion unlatching when the main pops once or twice. It also helps to turn the main under full compression with the fuel /governor control OFF before opening the throttle to start it. This allows the cylinders to get uniformly warm and makes for a clean start.

Remember that the pinion housing oil also lubes the starting engine drive train and mag gear! Dont compromise these parts just because the brake discs need replaced, repair the discs and use the correct 30W or equivalent oil. If the clutch keeps popping out then the pinion latch screws need to be turned in.

Tractor hydraulic fluid covers all the bases. Good for hydraulic pumps good in wet brakes, thinner than 30wt, all around good fluid.

Detergent oils started in the 50's and the discussion was on as to when to used detergent and non detergent oil. The rule of thumb was that if the oil was filtered, use detergent oil and if it was not filtered use non detergent oil. In our farm tractors back then (D4 Cat and IHC Super WD9) we used detergent oil in the engine and non detergent in everything else such as injector pump etc. When we switched from non to detergent oil in our Super H, we had all kinds of sludge in the bottom of the pan from prior accumulation with the non detergent oil. The only thing you have to be wary of is if you loosen a lot of accumulated crud with the detergent oil and it is now circulating the muck through the engine or whatever. I run non detergent oil in everything except the engines in my old critters. Nothing wrong with detergent oil in pumps, clutches etc if they are cleaned first.

"Rome wrote:

Remember that the pinion housing oil also lubes the starting engine drive train and mag gear! Dont compromise these parts just because the brake discs need replaced, repair the discs and use the correct 30W or equivalent oil. If the clutch keeps popping out then the pinion latch screws need to be turned in.

I tend to agree with Rome K/G on this. Its not a big job to make it right and not have to worry about what's not getting the proper lubricant.

How do automatic transmissions survive when filled with ATF? By Rome’s logic we should be using 30 weight motor oil in all automatic and power shift transmissions. We don’t, we use transmission fluids. The key difference between a transmission fluid and a motor oil is the additive package used in the fluid. Transmission fluid has both extreme pressure lubricants to prevent wear and friction modifiers that make brakes and clutches operate smoothly without slipping.

The Caterpillar pony motor gear train/pinion clutch compartment is NOT an engine crankcase, it’s more of a transmission/wet clutch/brake application. It doesn’t need the additive package of a motor oil and operates properly when filled with a transmission oil. If you don’t like the idea of ATF, use a TO rated fluid instead.

If thats the case then Caterpillar would have used atf in all later machines, but they DONT and never did recommend it. It's your baby you can do what ever you want to it, but I wont do it in my machines.

"D4Jim" wrote:

Detergent oils started in the 50's and the discussion was on as to when to used detergent and non detergent oil. The rule of thumb was that if the oil was filtered, use detergent oil and if it was not filtered use non detergent oil. In our farm tractors back then (D4 Cat and IHC Super WD9) we used detergent oil in the engine and non detergent in everything else such as injector pump etc. When we switched from non to detergent oil in our Super H, we had all kinds of sludge in the bottom of the pan from prior accumulation with the non detergent oil. The only thing you have to be wary of is if you loosen a lot of accumulated crud with the detergent oil and it is now circulating the muck through the engine or whatever. I run non detergent oil in everything except the engines in my old critters. Nothing wrong with detergent oil in pumps, clutches etc if they are cleaned first.

A correction to the time line here. Sometime in 1935 Caterpillar started recommending detergent motor oils for diesel engines. As I have related other times here,my grandfather bought a D35 in 1934. The dealer made a better deal if they could bring other prospective customers to drive it. Without proper break in and non-detergent oil it had a oil consumption problem. Cat worked on this engine at least 3 times in the tractors first year or 2. It was a combination of complete engine kit, break in and the brand new oil with detergent that solved the problem.

You are probably correct that in wheel tractor country diesels did not show up until the 1950's so there was no need for the detergent in the motor oil. So it would of been then that dealers would started promoting it,and would be talked about.