311-3500 Hydro Gear

[bgsengine]

Anyway drained oil and it looked like new.

Meaningless - since there is no combustion or fire going on, oil isn't gonna burn or collect carbon (which is what turns engine oil black)

No slivers in it of any kind. Magnet picked up nothing.

also means nothing - much of these are *aluminum* which will score and wear quicker than the steel motor blocks

Only thing I found was a piece of stuff that looked like gasket sealer that oozed out somewhere.

could have been. they're generally sealed with something like Loctite Ultra Grey RTV sealant

Refilled with 20W50 and put back in.

I suspect that will turn out to be a mistake - you can't tell if the unit is damaged without tearing it down and going over the motor block surfaces and inspecting the aluminum valve body blocks they run on - there are slots/holes for the oil passages and even a "hairline" score between holes will cause the problem you are having with the unit. - Both motor blocks should have been removed and their mating surfaces with the valve bodies inspected.

I'm going out to try to purge it and get it going in a minute or so. I'll let you know how it turns out. I can't see it being any better just by changing the oil but as easy as it is to remove I figured I'd try it.

Paul

Good luck, but if the problem is what I think it is, you probably missed it by making assumptions based on the oil quality and lack of visible debris.

[madmantrapper]

bgsengine, your points are well taken. I agree with them for the most part. The only thing I can say for sure is the 20W50 I put in is definitely thicker then what I took out. I purged it the way described in the manual. I could tell the difference in the unit instantly. Thinking it was my imagination looking for positive results, I got the grandson that uses it the most and he agreed there is a world of difference. Even the reverse that was sluggish brand new is much better. I can't imagine the thing having the wrong oil in it from the get-go. It would have never lasted this long I don't think. If it don't rain tonight, I am going to hook up the plow tomorrow and try it in the garden, plowing is where the problem showed.

[BLES]

Curious to know the outcome of this.?

A neighbor just asked me to look at his Craftsman lawn tractor (944.607940) that has a slipping drive system. Belt seems tight and everything right back to the pulley/fan/shaft going into the transaxle is turning even when the drive stalls out on a hill. I'm thinking the "hydro" is going. Likely not worth replacing on a high use, cheap machine.?

BLES

[madmantrapper]

Its been a couple years since this issue. The thing is still working like a charm, I don't know why. I don't use it for anything but cutting grass anymore.