Hydro Questions

Hey guys, so my main mower seems like it wants to be done. It has a pulley swapped hydro in it which is starting to act up. Anyway...

Before I really started abusing it every time I drove it underwater it would just quit. So I know that's some kind of a problem, could it be a busted seal? Anyway, I was reading a thread on here, and decided to purge it. It helped a bit for that day only. And then I started driving it at least a mile a day, up the 1/4 mile driveway to get the mail, back down at high speed, and somewhere in there down to the creek. Now it's acting up. So I hit the gas, start to go, and once I get about half way, It starts to lose power. Could it be an oil change? Water in the system? A dead hydro pump? I let it warm up first thing before I drive it. But I also drove it a little while without a hydro fan so do you think that hurt anything? Anyway I just need to know if it's trying to tell me that it wants to go out in a blaze of glory or if it just needs some maintenance.

BTW this is one of those el cheapo trannys that your not supposed to do self-maintenance on.

Hydrostatic transaxles are super sensitve to dirt/water, that's for sure. So I'm guessing that, plus the fact that it has been overdriven, was run without any source of cooling, and is probably covered in dirt has really done a number on it. It's most likely overheating and causing issues.

I've put a make-shift fan on it and cleaned it when it was out back in December. But it really started acting up when I thrashed it in the creek. So I agree. It's really a horrible tranny but it's been good to me considering how hard I beat it. I'll be putting a 5 speed in it soon but I need it right now so.

I also wonder if the added heat and rpm from the pulley swap is causing the oil to "foam" after a short period of use and ruining performance

Maybe. It's getting a lot worse. It barely made it up a 45 degree hill yesterday. It runs mint on a downhill but as soon as it gets under it's own power it's just dead. I've only got about a 1/4 pedal left at half throttle and I have a race against an FNR Troy Bilt coming up so it needs a bit more power to win this. Is there any way to flush this thing besides an oil change? I don't want to change the bezel or whatever it's called just to completely destroy it.

2 quirks of my hydo, querk 1, it leaks oil, if oil is low, its power is low, after amount a minute of run time. lower the ooil the less power.

quwerk 2, if i make it over heat from overworking it in the mud i start loosing power as well.

my personal plan is to put a oil cooler in the hydrolic line setup along side the oil filter.

Out of those two I'd say it's probably "quirk 1". Although mine doesn't leak oil at all, I have never checked it's level and it has probably never been checked. And like @Crazy_Carl said, Its new RPMs might be causing it to foam and/or evaporate. Just to get an idea on how hot it's getting every time I drove it in the creek you could see steam coming off of it when it was wet.

I'll try to throw some oil in it before the race and see what happens. What oil should I use?

Well, got some good news, It looks like it's fixed itself! It's faster than ever and ready for more abuse LOL!

So the Murray's hydro has been doing awesome! Especially with it's new belt and the warmer weather.

But I got a hold of another hydro, this time it came out of an LT1000. It's leaking a little bit, and when it warms up, and you try to go up a hill, it starts lagging. And if you slowly start off on a hill, it jerks pretty good, but I found a busted mounting bracket so that might be the jerking.

Also the axle was cracked and so was a brass bearing inside, and the thing on top (looks like a filter) was covered in tiny steel shards magnetized to the top.

Does anyone know what these things mean? Should I save it, or is the pump gone?

I bet your axle busted from the other page is the culprit of your lag and jerkyness.   Letting the axle spin in the wheel.

Murraymountain wrote:

If you want to try and fix, and it is not too $$.  Get a new filter, axle half, and throw it back together.  You will need to perform an air purge when you are ready to drive.  Maybe a few bushings.  Question is... is it cheaper to fix or source another trans?

Actually it was just cracked. Once I took the wheel off it fell out, so before then it was still holding the key. But besides the axle being cracked, it is also bent, just slightly, but it is. It's so badly damaged that when I take the axle out, if I drop it, I think it will split in half... I'll have to try that! It will need a new bushing... As you saw the old brass one is busted, and the axle had play in it because of that. Anyway, my main worry is that I get it all fixed up, get it back together, and it still doesn't work.

So that piece on top is the filter?

I just looked back at Rockey's answer to the Murray's hydro, and this hydro does have a leak. When it's cold and it hasn't been running it is very responsive, and when it's warm it's a lot less responsive, could it be a lack of oil?

I don't think I'll be putting this one back in... I plan on buying another LT1000 that's already been parted out, but it has a tranny, motor, frame, and a few other oddball parts. I'm just working on this one to pass the time.

So, I'm pretty much stuck with fixing up this one. The guy at the junkyard had some absurd prices, so here we go.

The pump and motor look fine, 99% of the time there's no slack in the bores. I'm gonna see about cleaning the filter out, and I still have to get the old RTV off. So the issues were: Destroyed axle and brass bearing, and an oil leak. That's all fixable, BUT, I found metal shavings all throughout the case.

So, what do the metal shavings mean?
Does anybody know where I can get the left axle half and brass bearing?
And what type of oil do these "Hydro Gear" trannies use?

Thanks!

Metal shavings mean it was used.

Okay, yet again, another hydro bit the dust. On these piece of crap Craftsman LT1000 Hydro Gear trannys, have any of you ever seen the seal burst in the back?

The tranny in the pics above had a busted seal in the back, and the old owner had been using it on some steep hills. Now the Craps-man blew the same seal in the same place.

So my main question is... Will these Hydro Gear trans. blow the seal in the back because of hills that are too steep? Will the pressure loss create loss of power?

Seal in the back???

Little vague, haha.

Haha, it's all one seal, it just likes to blow out in the back.

Like the case half gasket you mean?

Right, same seal we always replace with RTV on the MST's and whatever other type geared trans. we have.

Hey all. It's been 5 years since I've posted in this thread but I've been doing research and coming up empty handed on my current question so I figure it's time to consult some people who can come up with a pretty collective answer to a pretty specific question.

So, a fluid flush. Usually this would be as simple as draining the old fluid and adding fresh oil and if you really wanted to just draining it one more time and refill for good measure. I am faced with a new issue however. On my Husqvarna mower that had a locked up motor and rusted out deck, the hyrdo had a blown out input shaft seal. Went ahead and replaced it and was going to add fluid back to it and just decided to go ahead and change the oil. What I was met with was not comforting.



A clear indicator of water contamination plus a fair amount of metal. The metal does not concern me that much because I know there is not much I can do about that to remove it without a full rebuild and the tractor is not at all worth that. I just want to change the fluid, but I'd really like to get this contaminated fluid out of the system or at least brought to a much lesser extent. So my question is how would you go about flushing it? I thought about diesel and run the pump for a little bit with a drill motor but I feel like that just wouldn't end well. So what are your thoughts? How would you pull this off without damaging internals?

My hydro I had in Dirty Rat when it was Thor got water contaminated.  I was never able to get it out fully, even flushing new fluid through the system.  Kept coming out pepto pink.  Good luck my friend.

That's reassuring lol.


If I can't get it out it is what it is I guess. The mower really isn't in all that great of shape anyway and it drove fine before aside from being sluggish from the oil level continuing to drop from leaking.


At this point I'm thinking just some regular motor oil and run it with a drill for a while and drain and repeat maybe once or twice. From what I've read so far there's not much hope on getting it out without taking the pump itself out and everything.

The only thing I can think of is using is some sort of alcohol or methanol because it dissolves in water and is easier to get out it works on big tractors I just don't know about lawn tractors LOL

That could also be a possibility. I went ahead and went with the diesel route. I filled and flushed about 3 times and then once more with a concoction of random motor oils I had laying around. Ran the pump with a drill briefly each time. End result looks a lot better.

Here’s what I started with. Flush 1, 2 and 3 with diesel…





At this point, even though cloudy, the diesel was at least looking like diesel, so I called it there and did one flush with motor oil.



I could see through it pretty well and it didn’t change color very much so I was happy with that. Filled it to the top with 20W50 motor oil and put it back in. I got some other stuff to do before it’s drivable again, so when that’s done we’ll see how it turns out. Hopefully I didn’t just destroy a working trans lol.

Well, results so far, not good lol. I put it all back together and now I can’t get the trans out of tow mode. Feels like it might be internal. Really hoping its not. Anybody got any suggestions on how to get this out of tow mode? I couldn’t get it into tow mode when I got it. I’m assuming it went into tow mode at some point while the trans was out. It’s one of the one’s that have the lever on the side of the case.