1977 C-120 Sundstrand 90-1136 Help Needed

[Bentoolong 94]

I just purchased a C-120. I noticed the level is maybe 2" below the mark on the dip stick. It looks like it has 10W-30 in it. It looks like motor oil not ATF.

 

I don't even have this tractor running yet so I have no history other than assurance from the PO that the tranny was good.

I don't see any leaks on the tranny or at the axle seals for that matter. I feel no play in the axles so I'm thinking the outer bearings are good.

 

Where did the fluid go?

 

My assumption is that the seals are bad and the level in the tranny is basically below the seals so the leakage has stopped.

 

I'm reluctant to run the tractor much without putting some more fluid in it.

 

I'd like to put some fluid in (maybe a cup or so)and see how it responds (checking for leaks at the seals). If I see leaks I'll stop and drain the tranny/change the filter and seals and then fill it again with fresh oil.

 

Is that a good plan?

 

Oh and my push valve is stuck. I've been working on it with penetrant and a small pipe wrench. It is the slotted round shaft variety. 

 

Also, I have a wallowed out hub that someone has done some work on. It is loose on the axle but I can't get it off because the 1/2" bolt they installed broke off in the hub. More on that later.

 

Any advise on how to approach the low fluid issue?

 

Thanks

 

Bentoolong

 

 

 

 

 

Edited August 10, 2021 by Bentoolong

[daveoman1966 3,586]

All you can do is fill up with 10-30oil and run it till the pump/motor are warmed up.  Then, see if it has good fwd/rev power without fading out.  If it fades out, that's a good sign of internal wear...which can be remedied without too much effort and expense.  As for the broken set-screw bolt in the hub...I can only suggest to center drill it, then use an easy-out to try and remove it.  

 

[Bentoolong 94]

"All you can do is fill up with 10-30oil and run it till the pump/motor are warmed up"

 

Thanks daveoman1966,

I thought I'd put a little lube in and then see if I get any seepage past the seals. I figure what ever I put in it now will come out soon anyway. I know these things take a bunch of lube. How much?

 

Any recommendations on the 10W-30 brand?

 

I may just put some cheap stuff in there initially and then replace it with some good stuff later along with the filter.

[daveoman1966 3,586]

b-4 you fillerup with 10-30, wipe off any of the suspect seepage places...seals mostly.  After runninng it for a while, park it on a clean dry floor---or cardboard---and wee where it drips.  

 

[ZXT 2,394]

How does the oil look? If it's dirty, I'd go ahead and drain out whats in it and refill with new. Then run it, and after you get it warmed up, drop it again and refill. Can never have too clean of fluid in a hydro. 

 

Change the filter while you're at it. Wix 51410, and Napa 1410. Axle seals is my guess as to where the fluid went. SKF 11124 for the axle seals. 

[ZXT 2,394]

16 minutes ago, Bentoolong said:

Any recommendations on the 10W-30 brand?

 

I may just put some cheap stuff in there initially and then replace it with some good stuff later along with the filter.

I wouldn't be too worried about the brand. More so about keeping clean fluid in it and changing the filter fairly regularly. 

[Bentoolong 94]

14 hours ago, ZXT said:

How does the oil look? If it's dirty, I'd go ahead and drain out whats in it and refill with new. Then run it, and after you get it warmed up, drop it again and refill. Can never have too clean of fluid in a hydro. 

 

 

The oil looks clean...just not much of it. I'm gonna add some once I get the thing running.

Edited August 10, 2021 by Bentoolong

[Bentoolong 94]

Is there anything to tighten/lube/adjust in this area. Things work well in my mind but then this is my first WH hydro.

 

Thanks.

 

BTL

[Jeff R. 35]

I have read to not lube this area at all, but others will chime in that know more than I do.  You can adjust the tension of the hydro control, but I would look at the manual that is available on this site which will explain the process in great detail.  I would not make any adjustments until you have it running and you get a feel for the control to see if it is too loose or too tight.

 

As far as your push valve, this is a very common problem.  You have the right approach with the penetrating oil.  What I did was use lots of penetrating oil, then took an air chisel and gave it two short hits on the side of the shaft.  I clamped my vice grips on it and it broke free.  Now since I have it free, I turn it in and then back out once a year so it does not freeze up again.

 

Good luck.

[daveoman1966 3,586]

This 'Friction Control Motion Lever' only needs to be kept free of dirt and any debris.  By definition, it's design works on FRICITION and any lubricant defeats the purpose.  Accordingly, don't lube anything in this apparatus.  The friction adjustment is accomplished by the locking nut (#11) in my pic. Don't lube the NYLON cam either...  

[Bentoolong 94]

Thanks,

Just what I needed.

 

Bentoolong

[Bentoolong 94]

I'm adding some 10W-30 to the trans and after pouring the lube in I realized that the tranny is a closed system and I just plugged the vent. I got oil in a few places that I don't need it.

Is there a bolt I could loosen somewhere to allow air to escape some place other than the filler tube?

 

Thanks,

BenTooLong

[pfrederi 17,129]

Run a piece of wire down the filler tube alongside you funnel and pour slowly!!! The four seat support bolts in the top of the tranny are not drilled through

[daveoman1966 3,586]

Easy fill...No spill.

[rmaynard 14,864]

1 hour ago, daveoman1966 said:

Easy fill...No spill.

I've done this and I'll add one thing. Make sure that the bottom of the straw remains above the level of the fluid in the tranny.