My 876, just what HST do I have in it?

[Volfandt 7]

I started posting in another thread about my seal swap on my 876's HST axles and I've run into a new situation, so I've started a new thread so as not to hijack the other.

I ordered a couple 9878 1" axle seals from NAPA and picked them up today. With new seals in hand I went to install them and have run into a new situation.They wouldn't fit and thats because the HST in my 876 has 1 1/8" axles instead of 1" axles.

I searched all over it looking for an ID tag or stamping and only came up w/a tag w/90-2019 on the pump. I believe thats a Sundstrand model # and not a WH # but I could be wrong. My guess is the original owner must have swapped HST's.

Anyways, I looked up the 1276 HST model # which is 5054 and it came w/ 1 1/8" axles.The seal part number is 6449 and is still available from Toro. I crossed them to SKU seals which are # 11124 and NAPA has one in stock locally. I'll be picking it up tomorrow, I also have an 856 gear and the brake and axle seals have been seeping for yrs now so I went on ahead and ordered 3 new seals for it to. All the seals should come in by Wed.

So unless Wheel Horse let some 876's go w/the 5054 HST's from the factory, the original owner I bought the 876 from must have swapped the HST out sometime since he bought it new in 66.

I should have measured brfore I ordered but who'd have thunk about haveing a more beefier HST, kind of a pleasent surprise I rekon

Dave

[WH854 44]

I started posting in another thread about my seal swap on my 876's HST axles and I've run into a new situation, so I've started a new thread so as not to hijack the other.

I ordered a couple 9878 1" axle seals from NAPA and picked them up today. With new seals in hand I went to install them and have run into a new situation.They wouldn't fit and thats because the HST in my 876 has 1 1/8" axles instead of 1" axles.

I searched all over it looking for an ID tag or stamping and only came up w/a tag w/90-2019 on the pump. I believe thats a Sundstrand model # and not a WH # but I could be wrong. My guess is the original owner must have swapped HST's.

Anyways, I looked up the 1276 HST model # which is 5054 and it came w/ 1 1/8" axles.The seal part number is 6449 and is still available from Toro. I crossed them to SKU seals which are # 11124 and NAPA has one in stock locally. I'll be picking it up tomorrow, I also have an 856 gear and the brake and axle seals have been seeping for yrs now so I went on ahead and ordered 3 new seals for it to. All the seals should come in by Wed.

So unless Wheel Horse let some 876's go w/the 5054 HST's from the factory, the original owner I bought the 876 from must have swapped the HST out sometime since he bought it new in 66.

I should have measured brfore I ordered but who'd have thunk about haveing a more beefier HST, kind of a pleasent surprise I rekon

Dave

:angry-banghead: What is HST

Chas

[Volfandt 7]

:angry-banghead: What is HST

Chas

HydroStaticTransaxle

Dave

[WH854 44]

:angry-banghead: What is HST

Chas

HydroStaticTransaxle

Dave

Mate

Chas

[can whlvr 993]

you are correct that the nunber is a sundstrand number,and im not sure if it should have 1 inch or 1 1/8,my sundstand that is newer than yours from a c160 has the bigger axles

[pfrederi 17,881]

Is your hydro a gear motor or a piston to piston Sundstrand? The original hydros on your model were a gear-motor. That unit was not serviceable so over the years it may have been replaced with a piston to piston unit which was repairable. They may have re[placed the complete transaxle unit not just the pump/motor unit.

[Volfandt 7]

Update, I picked up an SKU 11124 seal from NAPA and this seal works!

After shineing up/deburing the axle I put a light coat of trans fluid on the axle and around the seal and popped it in. Even tho I had the tractor jacked up and at an angle (the removed wheel up higher) it still dripped out nearly a qt of fluid over night w/the old seal out.

Even tho the new seal is almost 1/2 as thick as the OEM I decided not to dirve it all the way in, instead I drove it in just beyond being flush w/the caseing. I poored in about 3/4 qt of Dexron, started it up and engaged the HST. It took a few secounds before it would spin the wheels (both jacked up off the ground) but it finally did and I took it to the extremes to try and get it bled off. It worked!

My dual spool hydraulic setup worked great too.

I've decided to leave the hub & wheel off overnight just to make sure it doesn't leak. so far after approx 1 hr it hasn't.

I don't know if it's a piston to piston or gear unit. How would one tell?

When I bought it I had to fix a leak behind the cam block and I also decided to change the fluid and filter. It had red automotive transmission fluid in it so thats what I put back. I used Dexron and it seems to works very well.

After looking at it again the HST is a different shade of red than the rest of the tractor so I'm convinced it was swapped out at one point. I'm actiually pretty happy that ot's got a beefier tranny in it but I don't know it's exact model number. I'm going to assume it's a 5054. in any case, I'll be measureing twice and cutting once from now on

1) a shot of the worng seals next to the OEM. The correct seal looked identical to these except it is 1/8" bigger. I got into too much of a hurry installing the correct seal that I didn't pause to take a pic.

2 & 3) a couple shots of the new seal installed.

Dave

[sorekiwi 761]

Glad you got it fixed Dave.

I picked up a rough 876 last year, and it had 1" axles in the transmission. I was surprised to find that, as I had assumed that all the hydro's would be the same back then, I didnt think it would make sense for Wheel Horse to spec a lighter duty rear end for just one model of tractor.

[pfrederi 17,881]

It is a gear motor..the hourglass shaped cast end plate is the give away. Piston to piston has a single round shped end plate.

[Volfandt 7]

Gear motor, thats good to know. It's still pretty strong. That new skinny seal seems to be holding Funny thing, the 876 has been marking it's spot for yrs, about directly underneath the HST, not enough to e concerned so I just kept an eye on the fluid level. Well it's been high and dry since I swapped that seal. It must have been weeping the whole time

Dave