[bartholomewbrian]

I'm in Ocala, FL and I have a JD 330 with 917 hours, which we bought used. It gets used about 30 hours a year for mowing. I do IT support for a living but I am a hobby machinist and shade tree mechanic.

Three years ago, the transmission fluid leak rate became unworkable. The implement relief valves were oozing, as was the transmission input shaft seal at the charge pump. I replaced the shaft seal at the front of the charge pump, and the o-ring behind the charge pump housing. The flat bearing surfaces inside the charge pump had circular markings different than the factory grind marks, but didn't any steps that I could detect with a fingernail, and all the corners and surfaces of the gearrotors were pristine. I also changed the o-rings on the implement relief valves, and the filter. The leaks stopped except small spits from the relief valves at startup or shutdown.

Now, after a long period of slowly increasing transmission fluid leak rate the leak rate suddenly became unworkable. At idle engine speed and with the transmission in neutral it leaks two drops a second from the charge pump shaft seal. Upon shaking the rear universal joint there was noticeable movement from the transmission input shaft bearing. I again bought the shaft seal, the big o-ring, and I got the shaft bearing.

After opening the charge pump, the area on the shaft where the needle bearings ride is depressed from the main shaft diameter, and measures 0.677 inches by micrometer. The area next to the rear measures 0.687. There are different polishings and marks on the shaft in each of the different areas, but except for the needle bearing area which is so deep it seems intentional, nothing catches a fingernail. I have the manual and with the marginal picture scans it looks like the shaft is supposed to be a cylinder from the splines backward. How could it be other than a cylinder? The needle bearings wouldn't expand in. The ends of the drive pin have polish marks, I wouldn't call it chewed up but it isn't brand new, either. There is also a step on the transmission housing flat face at the outside diameter of the big gearrotor, but no interior steps or scoring.

I am looking for advice about what to replace to put this mower back in service, and I suspect I am now in the market for a used transmission. I don't want to open up the transmission to replace just the shaft and then find other parts that need replacing. When I drained the ATF it looked and smelled good. The oil plug magnet had some metal ground down to a pigment fineness, there were no larger pieces I could feel between my fingers.

Thank you!
Brian

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Here is a picture of the reduced area on the transmission input shaft:

 

[coalminer16]

At a minimum you need to replace the shaft. Get a used pump from Ebay or elsewhere (cost around $250-cheaper then new shaft). Might be able to find just the shaft if nothing else in the pump is damaged. I have replaced a couple. The issue is the metal goes through the rest of the system and makes a mess of things. I took my brothers pump apart and the shaft was ate away in two spots. The swash plate pumps all had buffing marks from metal going through-it was all junk. Cam from a 330 as well so he didn't have an H2 and steering system to worry about cleaning either. I would advise if it were mine-get a used pump and replace all seals as well as taking apart the diff and cleaning as well as resealing. Less then $100 worth of seals/gaskets/orings for a clean system and piece of mind everything is good is worth it to me. I made the mistake replacing seal by seal as they leaked. Finally-I just replaced them all and no issues since on one of my 332's.

Hope this points you in the right direction.

 

[bartholomewbrian]

Thanks. The ATF I drained looked good, without a metal haze, so maybe the filter got a lot of it. When I clean the differential, should I use diesel as a solvent, a stronger solvent, or no solvent?

I found a pump on ebay, but it had a dented oil filter which gave me pause. I don't want to install replacement parts that don't have a reasonable expectation of service life. I think I'll place a part wanted request on the wanted pages here. I saw the 'donate 5%' proposal and I think it's a good one.

 

[coalminer16]

I wouldn't worry about a dented oil filter. First thing I would due is tear into it and replace all the seals and that would let you look at all the inside parts. Ask the seller and agree that if you find it bad-they refund or replace or something like that. The filters can be dented up from removing an over tightened one and then that same used one put back on to help seal up/keep clean the pump by putting a used filter back on.

I use starting fluid to clean all of my items anymore. Diesel can be hard on rubber parts that are made for it as can brake and carb cleaners. Starting fluid won't ruin seals. They are all flammable so not like it is much more dangerous. Just use where there is enough open air and no open flames. You won't see the metal in the oil. It would be adding less then a 1/4 teaspoon of fine grit to a gallon of dark oil-hard to see. You need to look at the bearing/bushing surfaces to see if it looks like there is fine buff. It is a dark-not a shinny buff to it if micro-scratched from the metal. The swash plate pump pistons should be shinny-if not-then they are buffed from the metal and junk.

 

[bartholomewbrian]

Hmm. I like eBay, but, hmm. Especially because I don't know what I am looking at in terms of what is reasonable condition for a hydraulic system.

The picture below is the surface texture I saw on the gear rotor. Page 90 of TM1591 in PDF says to inspect for "signs of scoring on the outer edge" of the rotor ring, but the arrow on the picture points to the corner? Is the "outer edge" what would be the sidewall area on a tire, the tread, or the corner between them? The tread area is in much nicer condition than the sidewall. The sidewall has circular marks, but my fingernail doesn't catch in them. The corner is sharp. Is anything other than a factory ground surface either polished or "scoring"?

I don't know what the specks are that look like particles in the picture. I have noticed generally that my camera pictures of metal parts reveal a lot more crud than by eye. I didn't feel these specks as particles with my finger tips. They aren't dirt from my hands, and they aren't dirt that fell in. Before I opened the charge pump up I pressure washed, sun dried, blew with compressed air, wiped until the paper towels came off clean, then draped the area with newspaper.

Thank goodness for this Internet thing, I'm getting a distance education in hydraulics.

 

[coalminer16]

That is the charge pump which drives the hydraulic lever. You need to tear into it further to the piston pumps that drive the tractor. If they are good you could find just a shaft. If bad-a whole pump. Hard to find just a shaft though since that is the part that always fails and the rest typically is good. Although-I did find a shaft once and it ended in my fathers 430 pump as a spare. His got the whole pump since I couldn't find a shaft at the time. Only the top relief valves were good from my brothers pump.

Back to the charge pump though-it likely isn't bad. The way to test it would be to put a gauge while tractor is running up front. If you get around 750 PSI then it is good enough. But-that isn't the thing right now to worry about anyways. Keep us posted.

 

[bartholomewbrian]

Monday I'll put in an order for the rest of the seals. I'm now in the market for a replacement transmission. I'd really rather get it from someone here, with the understanding that if pictures show it's too worn after I open it then I can get a refund.

 

[wmgeorge]

FYI If you would have used Locktite bearing and seal, the green stuff on the first bearing replacement it might of stopped the wear. It can take up a little slop but now its time for a new shaft.

 

[charms]

Bill, I'm quite sure this is one of those bearings where the needle bearings run directly on the shaft, so Loctite might not be appropriate.

 

[wmgeorge]

You are correct, only works on bearings with a race

 

[bartholomewbrian]

The previous mechanic replaced the transmission's hard tubing hydraulic pressure line and return line with hoses with crimped fittings. These hoses are in fine shape, but they are stuck and an open end wrench was rounding the corners. Currently I am trying a flare wrench with vice grips clamped over it to keep it from spreading, hit by a wood block and hammer. I am about to escalate to a cheaper pipe over the wrench. Is there anything else I should be trying before cutting the fittings with a hacksaw and using a six point socket?

 

[bartholomewbrian]

The flare wrench did not work, it just rounded one corner badly. What did work was Craftsman brand vice grips, a variety with flat serrated jaws that were about parallel at that size. There was less damage from the vice grips than the flare wrench. I believe this damage is just cosmetic, all the squeeze was on the flats and they unthread easily like the base of the threads is still round. The fittings are marked "Eaton 04U P06".

 

[bartholomewbrian]

The rear end is out!

 

[bartholomewbrian]

The replacement transmission has arrived, and I'm starting to install it.

 

[bartholomewbrian]

The tractor is reassembled and has mown a test strip.

I left the frame support bracket attached to the differential. After removing the rear end with the transmission supported by a dolly and blocking, I put a 2x6 piece vertically under the left bolt hole as a stand and attached it with a big lag screw.

Most of the surprises were small, related to rubber parts which were too stiff and crumbly. Replaced the suction hose. Replaced the check valves with the ones I had, as the new-to-me ones were stuck pressed down. Adjusted the length of the shifter linkage so movement stops in the neutral slot.

The remove transmission drain the oil manual page said about 5 quarts. The specs summary page said 6.5 quarts of oil with a filter change. The refilling overflowed at the air vent hole at the bottom of the oil fill hose at about 5.5 quarts. After the ten minute idle to purge air more oil went in, and after driving the tractor around the remainder went in.

 

[coalminer16]

Did you go by the sight glass or the manual. There is a few known things where the manual states too much oil to go in. An example is the rear 2000 RPM PTO. They spec more oil then it can possibly hold if I remember right.

 

[bartholomewbrian]

I went by the manual, which said 5 quarts to drain and 6.5 quarts capacity with filter change. I expected it was normal that the sight glass would be too high before the airspaces were filled. It overflowed through the vent hole at the bottom of the filling tube when the sight glass was about a quarter inch above the top of the range, so I think the temporary overfill was self-limiting. Eventually the whole 6.5 quarts went in.

My remaining transmission oil leaks are a slight ooze at the o-ring at the bottom suction hose fitting, and a drop at startup at the middle of one of the check valves. I think both can be stopped and I look forward to having an easier pre-use inspection for problems because normally it's dry.

 

[coalminer16]

I still advise now that you have ran it to go by the rear sight glass. Too much oil can be as bad as not enough depending on the application.

 

[bartholomewbrian]

Replaced plastic grommet material in hose cutouts in sheet metal partition behind hydro. Replaced fuel tank feedthrough bushings, one was oozing, and discovered fuel suction hose was on bottom of tank. Replaced o-ring on bottom fitting of suction hose, it needed it. Remaining ATF leak is at check valves, will look here for the alternative source to get better prices.

 

[andrewn]

I have a good used set of check valves that were not leaking when removed not long ago.

Shoot me an email if interested.