B6200 HST- hydraulic issues

[Weimsnks]

I have a 1982 B6200 HST 1200 hrs, 4wd, power steering,Loader,bush hog, that has two issues I can't figure out.

1. The crankcase keeps filling up. I thought the hydraulic pump shaft seal was bad allowing oil to leak by so I replaced the seal... no change.

2. This winter I went to push snow and when I went to part the tractor, I had hyd. oil pouring from underneath the seat. It looked like it was coming from a plate that was held in place by 4 bolts. I checked the bolts and they were tight. I have no idea what is under this plate.

I am fairly mechanical guy but I don't know the inner workings of the hydraulic system and I don't know where to find a schematic or the like.

Any ideas would be greatly appreciated,

Jeff

[Service Dept Vic]

Hi Jeff,

That plate with the 4 bolts is the cover for the hydraulic pressure cylinder. The piston that supplies the lift for the 3 point is under that cover.

Also on that cover is a valve handle that can be turned to divert hydraulic pressure to an aux port, or for another function, like a log splitter.

Make sure that it is situated "horizontal" position.

The cover has a couple of o rings under it, that may have popped out of it's packing gland, giving you the oil geiser.

It's safe to remove with the tractor off and 3 point down.

Hydraulic oil will pressure into the oil galley at the point where the two systems share space. The injection pump/hydraulic oil pump area is spot on for this type of infraction.

How certain are you that the seal you replaced was not nicked or damaged on the way back in? Was the hydraulic oil pump impeller shaft smooth as silk and shiny as a new dime, or was it rough and nicked, was there a groove on the shaft it when the new seal was slid onto it?

[Weimsnks]

Vic,
Thanks for the ideas.

The Impeller or the input shaft of the hyd. pump, did have a small depression where the seal would ride. It has been a couple of years ago when I did this but I do remember noting this in my head. I imagine this is the problem.


I am pretty sure the seal was not harmed when it was changed. My background is such that this repair was routine for me.

I will be sure to look for the diverter valve handle position. It is very possible it was turned and I didn't notice it.

Jeff

[Pat Pending]

Let's see... if the crankcase is filling up, the next question is, "with what?"

I'd start by checking for reduced fluid levels elsewhere.

Is is possible that the injector pump is leaking diesel into the crankcase?

[Weimsnks]

Let's see... if the crankcase is filling up, the next question is, "with what?"

I'd start by checking for reduced fluid levels elsewhere.

Is is possible that the injector pump is leaking diesel into the crankcase?


I don't think it is diesel. When I changed the oil, it did not smell like raw fuel had been introduced into the oil nor was it watery. If fuel were to get into the oil, I would expect it to be very thin.

BTW, the hyd oil level does drop off. That is what led me to my original diagnosis.

Thanks for the input. Can't have to much help.

[Service Dept Vic]

If that shaft had a groove, then the new seal would not be able to seal against that area of damage. Cleaning it up with fine sandpaper may leave the impeller shaft smooth, but under sized.

Before you replace the pump because of that worn shaft, see if a machine shop is able to source a Speedi-Sleeve that will fit.

[Weimsnks]

If that shaft had a groove, then the new seal would not be able to seal against that area of damage. Cleaning it up with fine sandpaper may leave the impeller shaft smooth, but under sized.

Before you replace the pump because of that worn shaft, see if a machine shop is able to source a Speedi-Sleeve that will fit.


Vic,
Would you have the nominal OD of the shaft when it was new?
There is a product that is a hard chrome finish. It has a Rc of 78 and when it is applied it only adds .0002" to the diameter. This stuff is used a lot on gun parts due to its wearability and slickness.

I also like your idea about having the shaft sleeved. I just happen to work in a high end machine shop that could do what you are suggesting.

Thanks for the advice and I will let you know how it turns out.

Jeff