125 Hydro Issue
 

Why would my hydro work at low rpms, but when I have the engine speed up for mowing it doesn't want to move? Last week when I was mowing I was having a similar problem, if not the same, so I took the relief valves out to make sure they weren't half open, and they're fine and seem to be working properly. The filter doesn't even have 100hrs on it.

How is the fluid level? 100 hours, how many years since both the fluid and filter have been changed? What are you running for oil and filter make and number?:bigthink:

Make sure roll pins are intact in driveshaft

Both Sam and Grandpa have the right ideas to start. Are you leaking any fluid at all?

The fluid level is good. The filter was changed either late last season or early this season. The fluid was changed a year or two ago with Hytran

That was the first thing I checked and they seemed to be fine

Nope, not leaking anything

Filter make & part #

I would change the filter and then cut and inspect the old one for any signs of parts or materials that don't belong.It sounds like you have done the most common parts to fail. Good luck,I also have and enjoy my 125

The spirol pins (what should be installed there, and not split roll pins) may look good and still be visible on either or even both sides of the coupler but still be broken internally, with one or both ends you may be able to see still stuck in the coupler.

I suggest you hold the coupler tight w/pliers and and try to spin the driveshaft while doing so with another pair of pliers or vise grips.

I have seen this issue before an 882 diesel which are hard on pins.
Both ends still in the coupler but the hydro input shaft not turning.
And when driving the old pin out, what's left of it comes out in pieces.
It may be tough lining up the coupler with the hole in the driveshaft when installing a new spirol pin, use a short length of 1/4" bolt shank to line the holes up and drive the new pin in while pushing the piece of bolt out the other side.

Good luck!

NOTE TO SELF: replace the pins in the 882 BEFORE heading to Bluneirs plow day in October!!