90-1136 rebuild

[gt14rider 765]

Here is a rebuild of a 90- 1136, before I get started I would like to thank @daveoman1966, @pfrederi and @Darby 1964 for helping me get the parts and knowledge I needed to get the job done. 

 

I have a list of all o-rings, seals, snap rings, bearings, gaskets, and some internal parts. And where to purchase them, I'm not very good at typing so bear with me, if I make a mistake let me know and I can make it right.

 

Remove four socket head bolts holding pump housing on.  With pump assembly held horizontally carefully remove the finned aluminum housing together with the input shaft.  NOTE:  Make sure the cylinder block and piston assembly does not drop off the input shaft.  Important:  If any of the pistons slip out  return them to their original cylinder bores.  remove roll pin on motion control, mark housing left and right and swash plate left and right. Left side (motion control) swash plate has two roll pins, right has one. punch them out, remove swash plate. remove snap ring, remove shaft and bearing, remove seals, check needle bearing, (replace if worn) replace seals, install bearing and shaft, snap ring, start roll pin in swash plate, replace swash plate, install washer and c clip on end of swash shaft, install motion control. Note: Change: 2 roll pins in stub shaft on swash plate. 

Edited August 14, 2022 by gt14rider
Add info,

[daveoman1966 3,752]

Any of these Sundstrand Pump I've ever dismantled had FOUR roll pins.  Your manual sez THREE...then THREE it is.  

 

 

Edited August 14, 2022 by daveoman1966

[gt14rider 765]

This is what is in sundstrand manual, is there a updated version of this manual?

[gt14rider 765]

Thanks, @daveoman1966     for the update. It makes  sense to install 4 roll pins, please keep updating as necessary

This model does not have hydraulic lift.

Disassemble pump end cap, clean, air dry, remove all gasket materials, clean o-ring surface, clean all check valve, balls, springs. Replace o-rings. 

 

Clean and dry charge pump, inspect gerotor (internal  and external rotors) assembly for wear and scoring. Replace as required. NOTE: the gerotor set is a matched unit. If charge pump housing is worn or scored, it must be replaced. 

Check needle bearings, check pump valve plate (both sides) remove any burrs, scratches or foreign material. ( hand lapp both sides.

Note: Pump cylinder block is different than Motor cylinder block.

Cylinder block and slippers need to be disassembled and cleaned (slippers must stay in original cylinder bores)

Tool to disassemble cylinder block is made up from 3/8" X 3"long hex bolt, nut, 3/8 sae washer and a 3/8" i.d. X 15/16 o.d. washer.      Compress spring enuff to remove retaining  ring. Disassemble: note ( small washer,  spring, big washer,  retaining ring  )   Scratch and burr free, hand lapp with 200 grit, 400 grit. 

Clean and air dry,  light assembly lube assembly in reverse order 

[gt14rider 765]

Got some parts. 

On to the motor, Note: (motor housing must have the webbing up on o- ring side or motor will run backwards )

Take off 4 cap screws and remove cover, remove snap ring, remove 4 bolts on housing, tap housing loose, careful not to let cylinder block and slippers to separate. Mark slippers and block, slippers must stay in original cylinder bores.

Remove slippers, remove 2 bolts from centering ring ( output shaft side)

Place end cap on press, ( make sure cylinder block and valve plate are seated on end cap housing) use press to press off cylinder block, remove retaining clip, remove motor shaft

 

 

 

Edited August 29, 2022 by gt14rider

[gt14rider 765]

Clean things up, new bearing, cleaned slippers and block, valve plate. Replaced washer, spring, retainer and retaining ring. New retaining clip