Let me tell you a story about how I broke my tractor

[82Caddy 851]

I bought a tractor for the sole purpose to get the loader from it for my predator swapped D series tractor.

 

 

Get this tractor home, loader removed and start to look at it a bit closer.  It's actually in really good shape.  Get the bright idea that this tractor is better then the other one I used to blow snow last winter.  Steering is tighter, hydraulics are stronger and quicker.  Yep, going to be the new snow blowing tractor.  Time for some maintenance.

 

Up first was to swap the K341 from the other D tractor and a tune up on that engine.  See problems and resolution HERE.

 

Noticed the rear end was seeping some oil from the left side axle seal. Perfect, good time to change the fluid in the rear end, put a new filter on and new axle seals.  

 

Tear into that project.  Both hubs come off without issue, it was like a miracle.  Stuck two screws into the axle seal, gave them a wiggle and out came the seal.  I'm thinking to myself, man this is going super slick, going to be done with this in a hour and it'll be ready for winter.  That's when it happened.  All the needle bearings for the axle bearing came sliding out.  

 

I think to myself, It's only another 12 bolts to pull the transmission (4 on top, 4 on the front and 4 on the rear axle for blade mount), 4 bolts on the manifold, 2 bolts on the hydraulic motor, 6 bolts on the transmission case, 1 snap ring for the hitch, 4 bolts in the differential, some seals and new needle bearings.  Sounds like a good afternoon project.  My wife was out running errands so I sent her a text asking her to stop at NAPA and get some bearings.

 

Everything comes apart easily, no issues with that.  Put the transmission in my handy dandy holder thing (it's really nothing fancy, just a pipe welded to a flat plate for the axle to sit in and another piece of flat stock that the front of the transmission case bolts to so it'll sit upright on it's own. Get the case split, notice a few other bearings that aren't in the best shape so knock those out and replace them with two others I had from another transmission (luckily I kept all the good parts from another transmission that the case was busted).

 

Replaced the needle bearings for the axles, new seals, new grade 8 bolts in the differential and put it all back together.

 

No here's where tragedy struck.

 

 

Just like that, for some reason unknown to me, I removed the bolts holding the hydraulic motor together.  I have no idea what I was thinking.  Did a quick visual inspection, didn't see anything out of place, so I bolted it back together and onto the case it went.  Put the transmission back in the tractor, new o-rings and crush washer on the manifold.  Tightened up the tow valve on the pump, put new filter and oil in the rear end.  Fired the tractor up.  Zero hydraulic pressure.  No movement from the wheels, no lift from the cylinders.  Check the oil, little low so added a bit more to get to the full line.  Still nothing.

 

I can release the tow valve and I can pull the tractor so the rear end isn't locked up.

 

 All hydraulics worked before I pulled the rear end out and opened the hydraulic motor by accident.  I have not touched the hydraulic pump except the tow valve.

 

What else do I need to look at to sort out what is wrong with this?

[pfrederi 17,903]

how far did you disassemble the hydro motor?  Just remove it from the transaxle or did you go further/?  Do a pressure test on the charge pump lets see if that end is working OK

[82Caddy 851]

I pulled the wrong bolts out of the hydro motor so the case separated but did nothing further.

 

Stolen image from google.

 

 

The 9/16 bolts around the outside.  

What is the easiest way to test the hydro pump?  That wasn't touched and worked before I pulled the rear end out.

[pfrederi 17,903]

Messing with the hydro motor would not likely cause a problem with the implement lift.  That is why first i would check pressure to make sure that isnt the problem.  If you put the motor on upside down the tractor would work but the motion would be backwards from the control lever position.  Maybe something block the suction line intake (with the mesh screen??.

 

Pressure test

[82Caddy 851]

Interesting, I'll see if I can rig up some sort of device like that this evening.  Thanks for the suggestion.

[pfrederi 17,903]

Another thought.  Are you sure the O rings between the manifold and motor are correct and stayed in place during install. (I use some grease to hold them in place.)  If the suction line one is not correct or correctly in place the pump may be sucking air and not able to prime itself...just a thought

[82Caddy 851]

Did a redneck pump test, aka I loosed the pressure line to the lift  and started the tractor.  There was a dribble of oil.  Not spraying like I had hoped.  I'm thinking there is something blocking the suction from the rear end or the o-rings failed and are letting air in as @pfrederi mentioned.  I ran out of time/desire to work on this last night before I could check anything else.  

 

I can't imagine a pump would go bad from pulling the rear end out, I guess stranger things have happened.  Going to try new o-rings and crush washer to see if that fixes things.  If not, I'm at a loss and it'll get pushed to the side.  Have too many other things that need to be done while it's still nice outside.

[82Caddy 851]

Update, new o-rings and crush washer installed again. Same thing. No hydraulic pressure. 

 

Tractor rolls no matter the tow valve position. 

 

So not building hydraulic pressure. I'm wondering how difficult it is to rebuild a pump...has to be cheaper then the 270$ ones I see on eBay. 

[pfrederi 17,903]

Could be a tow valve issue.

 

Rebuilding the pump is doable but not a real easy job.  The actual work on the pump is fairly easy.http://www.wheelhorseforum.com/topic/32936-rebuilding-a-hydro-pump-from-a-d/

 

The hard part is getting the pump out of the tractor.  I am convinced that when WH built D's they had a guy hold the pump in the air and then assembled the tractor around it.  If you have an FEL and/or a rear PTO, or an easy ride seat it is even more fun.

 

The sundstrand manual pretty much details how you go about removing the pump, and how to disassemble it..  You will need (or at least want) to have a long 5/16" allen socket and some 12 point sockets  (I think 3/8 and 716 but I need to check that)

 

The ebay pumps are a pig at a poke.  I have bought a few over the years all from " good working tractors"  Yeah right, after opening them up some of the tractors must have been towed/pushed to the scrap yard.  A couple were usable but needed some work.

 

EDit:

If you do get a used pump I would open it up and go over it carefully .  It is way to much work to pull yours put in the new one only to find it has issues.

Edited August 11, 2016 by pfrederi

[82Caddy 851]

1 hour ago, pfrederi said:

Could be a tow valve issue.

 

Rebuilding the pump is doable but not a real easy job.  The actual work on the pump is fairly easy.http://www.wheelhorseforum.com/topic/32936-rebuilding-a-hydro-pump-from-a-d/

 

The hard part is getting the pump out of the tractor.  I am convinced that when WH built D's they had a guy hold the pump in the air and then assembled the tractor around it.  If you have an FEL and/or a rear PTO, or an easy ride seat it is even more fun.

 

The sundstrand manual pretty much details how you go about removing the pump, and how to disassemble it..  You will need (or at least want) to have a long 5/16" allen socket and some 12 point sockets  (I think 3/8 and 716 but I need to check that)

 

The ebay pumps are a pig at a poke.  I have bought a few over the years all from " good working tractors"  Yeah right, after opening them up some of the tractors must have been towed/pushed to the scrap yard.  A couple were usable but needed some work.

 

EDit:

If you do get a used pump I would open it up and go over it carefully .  It is way to much work to pull yours put in the new one only to find it has issues.

 

 

I think you're right about it being a tow valve issue.  Either way, it looks like the pump has to come out eventually.  For now, I'm going to take a break from this tractor as I have a few other more important life related things to focus on.

 

Good news is this tractor is a pretty bare bones one.  No rear pto, no comfort seat, no loader.

 

Other good news is I have all of those tools.  Plenty of allen key sockets (long, short) as well as a full set of 12 and 6 point sockets.

 

 

[82Caddy 851]

Update on this:

 

New to my hydraulic motor, new paper gasket between motor and case, new o-rings/crush washers and all seems well on this.  No idea what I did the hydraulic motor when I pulled those bolts out but it was an expensive and stupid mistake.  Blower is on with a new belt on the way so it'll be ready to rip some snow this winter.