782 rear end problems

[bbungard]

I have a 782 that I saved from the scrape yard and I have been redoing it slowly. I put a 18hp briggs in it and I mad a new drive shaft and coupling. I figured I better make sure the rearend is good before I paint the tractor. So I hooked it all up and pushed the gear lever forward and nothing so then I tried reverse and nothing. So now I'm wondering if this is y the tractor was on its way to the srap yard in the first place. Looking for some good ol' know how on how to trouble shoot the rear end. Thanks guys

[ksanders]

I'd start with double-checking your oil level, then make sure the linkage is all hooked up and the trunion is actually moving forward and backwards when you move the lever, make sure someone didn't put manual relief valves ons it that aren't stuck down. Then being a 782 you have the huge advantage of seeing if the hydro lift is working which will tell you if the pump is actually pumping oil to start with. That's where I'd start.

[AJGross]

I would also check and make sure that your replacement engine spins the same direction as the oe engine. I would help you out and tell you which way a kt spins, but I don't know off the top of my head.

AJ

[mgonitzke]

The engine needs to be turning CCW when viewed from the front of the tractor.

[Jlaws]

If the 18 briggs is a opposed twin , it turns the same direction as a kohler twin . All the previous advice is good and I'd do what they suggest first ( check hytran level and relief valves etc. )
Theres is a hydraulic service manual in the Document and Manual section on this site and it shows how to install a guage to actually check your pump pressure .
Its for the QL series , but its the same pump used on a 82 series and I've used it to check several of my cubs( both QL and 82 series) .

http://www.cubcadetcollectors.com/manua ... temId=6458

One other thing that might be the cause of your cub not moving is something could be amiss in the rearend .
Its not likely but they don't move to well with a broken axle ...LOL... BTDT
I believe the 782's have external brakes and the rotor and brake assembly will hold the axle from coming out .
Easy way to check is to jack both rear wheels off the ground and spin one of the wheels , the wheel on the other side should rotate in the opposite direction .
When rotating the wheel listen for any unusual noises .

[bbungard]

The briggs is the opposed twin and I mounted it with the fly wheel towards the back of the tractor. I did jack it up and spun the wheels everything turns freely and the other wheel rotates the other direction. I checked all thelinkage its all free and moves easly. The one thing that concerns me is the tractor is easy to push around. I didn't think that a hydro tractor could be pushed easy. Did I mount the motor the right way? Thanks again for the help

[Jlaws]

Yeah , you mounted it right , flywheel towards rearend . Hydro's usually don't push easily . Did you check the rear coupling that mounts on the input shaft of the hydro pump , sometimes the spiral pin shears off and the coupling spins on the pump input shaft . If thats OK and the hytran fluid level is correct , then it has to be a pump issue or relief valves stuck open . Although i find it hard to believe both foward and reverse relief valves would fail .
Does it have the manual or automatic relief valves ??
It should have the automatic ones , but they could have been changed at some point. There interchangable and both will work .
The manual valves have little pins on top that sometimes get stuck down and are supposed to pop up when the tractors running . And if there the auto valves , they have a hole on top and they usually leak if bad .
You really need to check your pump pressure .

[mgonitzke]

Does the hydraulic lift work?

[Racenitro]

It sounds like the relief valves are the problem. If you have another hydro, steal the relief valves out of it and try them in the 782. They do go bad and I have had several that acted exactly like this. Every time it was the relief valves.

The automatics have a tall over 1" tops that are 6 sided to fit a wrench. The older style have a thin top with an approx 1/4" pin stickin up. The pin needs to move freely and stay up,

[mmzullo]

Broken carrier could also be the problem. BTDT also.

[Ln782]

I just recently had my 782 stop moving and jlaws posted "when rotating the wheels listen for any unusual noises" and I am getting a clicking noise. Any clues that this might indicate?

Thanks for your help

[ronniec]

i see you all say check oil level but how about the color how long has it been in there take a sample out from the back feel it this may be the issue on mine we had metel in it but by what hes saying the pump is the issue just my 2 cents ronnei

[Farmallgray]

I would pull the rear cover. That way you can eliminate the possibility of a broken carrier or ring gear. It will also allow you to clean all the goo out that hytran turns water into over 25+ years of use.

[bbungard]

Long time no time haha i havent gotten around to messing with the 782 yet. I came across a deal on a pair of 105s with 3 extra motors i couldnt pass up and ened up building them up and selling them..so now i think this week im gona try to get back on the 782 and see i can find i will post another update......thanks again guys for all the help

[bbungard]

I have been very busy with work...5 12s last 3 weeks and with the fire dept. (We got our new tanker) But i did manage to check the relief valves and they didnt seem to be stuck. I didnt pull the cover yet.....but thats my next move...im gona try to do it in the am when i get off work.... anything i should look for that is common on these rearends to break? O and i forgot to check the lift so i will do that first. If the lift doesnt work what should i do next? I found a 1710 i can pick up for 200....will that rear end work in the 782?

[VScott]

Brandon, The 1710 is just a 682 in different clothes ( a 1711 is the same as a 782, and the 1712 is a 782 with dual hydraulics). All three were made in 1985 only. The 1710 (if it hasn't been modified) will have the aluminum rear end, and I couldn't see anywhere that you posted if yours has an aluminum rear or a cast iron rear. Either way, it will work, but the 1710 may or may not have the ported hydro pump. Most of that vintage did, and the ports were just capped off. If it has the ports, you are in business. The cast iron rears in the 782s were internal brake, the aluminum rears will have external disc brakes. If you do a total swap, make sure not to hack up the brake parts, you will need the rods and all. Having the donor tractor right there will be nice. Also, be sure the aluminum rear doesn't have the bolt holes stripped out, or the housing isn't broken, both common issues.

I was sort of hoping that you would have found the problem with your exixting setup, I'm having the same issue on a 1512 diesel. It wouldn't roll at all when I got it, then after draining the fluid, it rolled fine. Replaced the fluid (looked like buttermilk) , filter, and valves, and it still won't pull itself. When it's jacked up (rear tires off the ground), both wheels spin in the direction that they should. The hyd. lift is very weak, and as soon as the tires touch the ground, the hydro is too weak to allow the tractor to move. I am figuring on a complete rear end swap from a 782 that I have here, if I keep ths one. I may be doing a 982d with this one as a donor.

[bbungard]

Got sme time to work on the 782 rear....wow what a mess. The fluid looked like driveway sealant mixed with cow sh*t...got it all tore down and tore the pump apart and got it all cleaned now i need to order gaskets.....

[bbungard]

Filter housing.....

[bbungard]

They rear end is cast iron....but the axle tubes are aluminum .....is this right? The left side axle tube(while sitting on the tractor) as some marks on it. It looks like it had a clamp of some sort on it and it came loose and put were marks in the axle tube..any idea what could have been bolted there?

[bbungard]

Sorry for the poor pic quality. I took them with my cell and had to resize them.....actually i do it all from my cell......anyways.....got to love purple power degreaser and my hopped up pressure washer

[Jlaws]

Brandon yes the aluminum axle tubes are correct on the 82 series . The older cast iron ones will work , I had to change out one of my aluminum ones on my 782 because it was cracked , i didn't have any spare aluminum ones , so I went with the cast iron ones. Having a bad case of OCD , I changed out both tubes .

As for the mark on the axle tube , I've seen similar marks caused by a tire chain that had moved ( slipped ) . Doesn't take long for a steel tire chain to do that to aluminum tubes , And the operator wouldn't hear it if he was mowing or operating a snowthrower etc . Just one possibility , does the mark go all the way around the tube ?

[bbungard]

That makes alot of sense.....yes the marks go all the way around. I took a tire chain and the marks and the chain are pretty close..

[Tom Scott]

Brandon - You look like you are doing a good job. Since you have torn the whole hydro down, take the time to check all the parts for proper clearance. The axial pump and motor blocks as well as their pistons could be worn to the point they need replacement. The Cub manual should give you all the measurements and checking procedures.

I rebuilt the hydro in my 1861 which is the newer, lighter duty version but of a similar design. I found that the pump block had excessive wear. I decided to replace both the hydraulic motor and pump blocks and pistons (sold as assemblies). I also had grooving in the pump swashplate where the nose of the pistons ride. Slightly different design, but you get the idea. Check everything and do it right the first time while you are already there.

Keep everything for the hydro surgically clean. Use paper towels instead of rags as they leave less lint. Use Hy-Trans for lubricant as you re-assemble. The charge pump gets packed with clean petroleum jelly to insure instant pumping when started. Follow the manual. You have done most of the hard part, only a little more work for a perfect job.

Lastly, Cub wants a fortune for Sundstrand parts, but I found that my local Sundstrand distributor would sell to me directly for much less money. I think their website has a look-up for distributors by zip code.

[bbungard]

Ok so all is going well on the pump going back together....until I got to the hyd motor cylinder block valve plates....Haha in my terms...the plates that go on the back side...they are different and I don't no which one goes were...any help? Thanks ahead of time

[bbungard]

Everything is together. Im just waiting on a pump shaft seal..

[vince_o]

Man looks good. Im getting ready this weekend to build another cast iron to putin a super. Amazing the crap that in these rears aint it.

I so enjoy following builds and works in progress!

[bbungard]

Need some help .......and maybe a cold beer Haha...I put it all back together and into the tractor..started it up and I have nothing.....no forward no reverse no up or down.....time to go back to step 1 again ....can I take relief valves from a 105 and put in this? To check if this is my problem?

[Farmallgray]

Did you mark which way the charge pump was on when you took it apart? If you have it upside-down it reverses the input direction and won't pump.

[vince_o]

Toodsright. I did that in a 2000 series once. Had nuttin and reinstaled the gear, waaalaaa it moved.

[bbungard]

Ummm no I didn't...looks like I have to tear some stuff apart tomorrow