looking for some insight or something... tow/push valve?
here's the story:
1973 14hp 'no-name' auto w/ sundstrand.
this has been driving me mad for the past month. In new england, the last big storm we had where it dropped 12"+ of snow through most of north central mass. the wheel horse died in front of my neighbor's car and would not restart that day no matter what. I opened the push/tow valve and pulled it backwards with my truck (about 40ft) slowly, I'd say walking speed or slower to a spot where it can be for some time, if needed.
the next day, I get it started and start plowing again and the tractor develops a really weak reverse after a few minutes but still some decent forward power. consult with a friend who does tractor repair for a living and he suggested draining all the oil from the hydro and putting in fresh oil and making sure the linkage/chassis bolts were all tight.... 10w-30w is what was in it and what was refilled with and the hydro filter is changed every year and all the bolts were tight - did this on a saturday. After refilling, I turned the pulley on the pump over by hand with the trans in neutral.
Tested it out an hour later and it now had a weak reverse even when cold. Let the tractor sit until the following tuesday morning and it was back with full power in reverse and forward.
I don't remember if I opened and closed the push/tow valve at that time.*scratch head*
talking to a couple more friends -one a wheel-horse fanatic- suggested maybe an internal gasket getting ready to let go or it was a sticking valve.
I then let it sit due to 'rainy/wet/cold/mud season' new england spring weather for the past couple weeks. Last week I freshened up the engine with new piston/rings/gaskets. I pulled the engine off yesterday to double check something but had to move the tractor chassis so I opened the push/tow valve to push the tractor 4-5ft put the engine back on and this morning the tractor acted up with a weak reverse again after a few minutes. which makes me think something is wonky in regards to the push/tow valve - either a piece of crud/varnish or I-don't-know.
I've read through various wheel horse/sundstrand manuals but I have no actual repair/rebuild experience what-so-ever with the hydros.
I'm at a loss as to the how/why. anyone care to offer any ideas/insights as to the how/why or what I can try to rememdy this problem.