Time to Repair 1572 Driveshaft - What Would You Do??

[mgonitzke]

The hydro pumps are NOT the same...reduction ratio is different. I wouldn't change the rear, either. You would need to drill and tap a 1/4" hole in the center of the input shaft to retain the coupler on the 1572 rear.

The input shaft on the 1572 is splined, and if the 1541 is a later one (like the parts diagram you show), the pump is different and has different splines.

Basically, you will need to lengthen the 1541 driveshaft and get the adapter to put the CV joint on the diesel engine. If you happen to have a lathe it looks like it would be easy to make. If the 1541 is the later one with the Hydro-Gear pump, you'll need a different input shaft coupler than what the 1541 has.

Hopefully that makes sense...I haven't gotten a lot of sleep lately.

[Tom Scott]

Bryan - All Supers have the Sundstrand 15 series hydro. The hydro you show for the 1541 is the later pump that Cub switched to for the regular GTs and that they still use to this day in the 3000 series tractors; it is a Hydro-Gear BDU-21. What is really important here is:

1) The 15 series hydro is stronger and you wouldn't want to replace it with the BDU-21 even if you could.

2) As you suspect, you cannot just swap in the BDU-21 in place of the 15 series.

3) Although you could take the entire hydro and rear from the 1541 and swap it in, that would be a poor choice because of #1 above, and because the Supers are geared lower to make up for the taller tires.

4) Even if you had a 15 series hydro, I believe it has to be one from a Super; the regular GT has a different output shaft on the hydro.

I would just buy the new parts required to make it like it was originally. I have both types of drivelines (rag joints and CV joints), and although I acknowledge that the CV joints are a better engineered system, you have to give the rag joints credit for lasting over 20 years in many cases. Just make sure that things like the bushing ball are not worn and have a good fit to the drive shaft and coupler.

If the rag joint dollars get too high due to many worn parts (couplers, motor plate, etc.), then you can punt and justify buying the CV joint driveshaft assembly. You will have to drill the input shaft of the hydro to accept a bolt for the new style coupler, but it has been done by others here while still in the tractor. I am sure they will provide additional useful information.

If you could get a used CV driveline from a later Super diesel at a reasonable price, it may be worth it, but new good rag joints and other hardware will make the original system sound again.

[jrarick]

Bryan
I would keep it original. If part 7 does not fit pretty tight on the trans input shaft it will cause vibration for sure. That part wears inside over time. I bought one from cub last year for my 1772 so they are available.
Always good to change any other worn parts while you have the driveline out. As a tip I suggest using new nuts and bolts from cub. They are pricey but they come with center lock nuts and are the correct size and hardness. I learned this the hard way.
Jim

[Farmallgray]

I'll add another vote for keeping it original.

As I have mentioned before, I have yet to be convinced that the CV joint setup is an improvement over the rag joints.
They don't have anything to cushion the shock. I always thought the rag joints were somewhat "sacrificial" so they would wear out rather than a more expensive part. With the CV joints, something is still going to wear and when it needs replaced it may cost a lot more than the rag joints.

Some day I may explore the possibility of changing one to Lovejoy style couplers.

[red82s]

My 1572 had the wobble and all I needed to do was change the bushings and a few other things. My input coupling does fit loose on the input shaft so I refrained from using it til I get the coulping ordered I figure as little as the drivetrain vibrates now it'll be even better with a new coupling with a snug fit on the input shaft. I'd go the original route as well unless you have all the parts you need on hand.

[Racenitro]

I use cold rolled stock and make new shafts when mine wear down. Put new busings on both ends. I don't put the release back because it is too much weight ont he shaft and a tiny bit of wear causes it to wear faster due to the extra weight being off centered.

[red82s]

Since were on the topic of the driveline, my 1572 doesn't have the clutch thingy on the driveshaft. I believe BB had a regular super driveshaft modified to fit but can't remember maybe it didn't need to be modified. If I were to ever need to replace my driveshaft what part number driveshaft would I order and would it still need to be modified such as shortened etc... thanks

The more i think about it, does it even matter if the driveshaft has the clutch? Is it the same driveshaft anyway? I may have completely misunderstood BB it was a while ago.

[Tom Scott]

Todd - I too like the simplicity of Lovejoy couplings, but they were not designed to handle large misalignments. Lovejoys are generally used in close-coupled machinery where the shafts can be made as close as possible to the exact same axis, generally measured in thousands of an inch.

The rags joints and CV joints specifically address the necessity to deal with the inherent misalignment that is present with these shafts.

Between my tractors, I kind of like the simplicity of the rags better; one less thing to grease during maintenance! And my 1872 is every bit as smooth as the CV joint tractors.

I agree that the weight of the disconnect clutch could make the vibration worse. If you can achieve easy starting without it, I would not want it in the driveline.

[mgonitzke]

No, the splined coupler on the supers is it's own thing...there is no substitute.

[Farmallgray]

Great discussion guys! I think I'll replace parts and keep the driveline original.

Now for a twist - would you still do the same thing if it were a GT diesel (782D, 882, 1512)?

That would be a yes.

[Paul B]

Todd.
I don't believe the Love Joy coupling would hold up, think there would be too much initial "shock". Jim Chabot played with LoveJoy couplings trying to couple two K series engines together for a CC based 2 engine, 2 transaxle, road grader project, and had some breakage problems. Part of the problem was the way the engines were timed to each other, and I don't remember if he ever got that straightened out or not.

[Doog M]

Paul
I think you are talking about this project. I had to look hard for that

[Paul B]

Yes Doog, that's the one. I don't know if he ever got beyond what you see with it or not. Oh, Jim...........!!!!!!

[bbaker]

Adrian, your tractor has a shortened 1872 shaft in it. It did have the clutch in it, but it was loose and sloppy and it appeared to me it would cause more driveline wear than it was worth so it got a straight (unclutched) shaft.

[AJGross]

Nice shirt there BB!

AJ

[red82s]

Thanks for the info BB I thought that's what you told me.

[red82s]

Did you move the engine forward to make things easier? I may have to try that when there's a next time. I've removed the entire driveline twice without messing with the engine. It definitely wasn't fun but did it in about an hour.

[jrarick]

On my 1772 I remove both spirol pins, slide the front coupler back and take out the 3 bolts holding the engine coupler. This allows the driveline assembly to come out. Last time I had it out I replaced the bushings on the disconnect clutch. Took the "slop" out. Just the way I do it.
Jim

[red82s]

Mine doesn't have the disconnect clutch so I can imagine it's a pain with one. That must be why I was able to skip step 7. I bet that'll be nice and smooth when you're done and hopefully you won't have to mess with it again for a long time.

[Racenitro]

Paul B.
What Jim C should have used to connect his two engines together is a Double Roller chain and two sprockets. One on each engine with the flat face facing the opposite engine. Putt he roller chain around the two sprockets. This is how we connect two racing engines or tractor pulling engines together. Also, JD combines and others use this to power the headers.