'49 A - Is there a step by step...

1 Deere

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I'd like to find a step by step procedure for trouble shooting a rockshaft repair on my '49 A. Simply put, it does nothing. I do have a new cup kit for the cylinder/piston but don't know if I need to go that far. A link to a step by step would be great.
Thanks.
 
If you had an owner's/operator manual it would probably help you out quite a bit. First thing is to check the oil level in the Powr-Trol unit, then see if the PTO is turning when you put it in gear and engage the clutch. If there's any oil circulation at all it should roll the rockshaft even if it needs a seal kit...unless the seal cup is totally shot and bypassing so much oil it can't even overcome the return spring's effect. Still no luck, better get some kind of service manual like an I and T manual at Tractor Supply if you can't locate a regular JD repair manual. Mebbe someone on the JD page can help you step by step better than I.
 
Yes to all of the above on oil level, PTO and flow metering. I'll go back to the I and T manual see if I missed something.
The rockshaft has never worked in the few years that I've had it. I even tried to help it with a 16" Crescent wrench with no sign of it even trying. I am not sure that the Hyd pump is working at all because I have nothing to hook up to it to try it.
I tried posting this on the correct forum... not sure why it ended up here.
Thanks.
 
Since the rockshaft has never worked for you here are two things you can check.

If the hydraulics were last used to operate a remote cylinder, the metering screw on the valve housing may have been left turned all the way "in". Remove the 1" long cap nut on the left side of the valve housing and loosen the jam nut. Then see if the metering screw is turned all the way "in". For rockshaft operation the metering screw should be turned 2 turns "out" from the fully seated position.

If the tractor had a "live" pump installed before you got the tractor, the idler gear in the pto driven pump may not have been reinstalled when the live pump was removed. Look at the drain plug on the bottom of the rockshaft housing. If the plug is 3/4" instead of the original 1/2" a live pump was probably installed at sometime in the past. If so, remove the pto shaft seal housing and the pump cover and see if the idler gear is there.

You can look at the A parts catalog (PC675) at jdparts.com. Check pages 124 and 126.
 
Thanks Pete
At this point, it'll be a little bit before I can create room in the shop again but when I get good info, I hang on to it and will certainly cover these bases once I get it in the shop. It was just one of those things that keeps bugging me, so I had to ask.
The previous owner was a mechanic and he didn't even investigate the problem. He just said that the rockshaft didn't work. He also was fine with running it with a 53 carb that was worn out and out of adjustment to the point where he always ran it with the choke pulled out a third of the way. That didn't fly with me for long at all before I bought a good used 71 and rebuilt it.
This tractor has a pump on the governor, so I am doubting that it also had a different pto pump... but we'll see.
 
The tractor originally came with a pto driven pump which is located just forward of the pto shaft. It was disconnected when the governor pump was installed by taking out the idler gear as I mentioned.
There are several things which could be wrong inside the governor pump that will cause a lack of hydraulic pressure. When you get ready to work on it send me an email and I'll help you with it. [email protected]
 
I guess that I just don't understand what one would have to do with the other and why they would have to disconnect the pto pump for the sake of the governor pump when they are so remote from each other and use separate reservoirs etc. but the missing gear in the pto pump would certainly be an issue. Otherwise, the governor pump works fine.
I will hang onto your email and appreciate this offer.
 
Do you have the dummy plugs installed in the powr-trol box or the plugs for using hydraulics?

Go to www.jd40.com and click on powr-trol on the left hand side of the page, he explains a lot about how they work.
 

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