Outdoor Power Equipment and Small Engines - hydro static drive help please????

I have a sears 17.5 riding mower with hydrostatic drive. After mowing for an hr the hydro stops working. If I shut it down and let it cool for 1/2hr I can restart and finish my lawn (1 Hr.).I have tried purging the system which seams to work, but after about a hr it happens again. This started happening after I tipped the tractor up on it's rear wheels to change blades/clean deck. Any help would be appreciated.

Thanks Tony :thinker:

How about a sears model number. Most likely will start with 917.

This is a total guess on my part without model numbers, but depending on how far you tilted it, you may have spilled some hydro fluid out of a vent on the top of the axle and now you are low on fluid.

Maybe you spilled some oil on the belt when it was tipped up, and the belt starts to slip when it get hot. That wouldn't take very much oil.

Thanks! here is my Model # 917.272220

I agree...oil will spill out the vent when you tip it. You can gain access to the top of the tranny by removing the battery box. Use 20-50 synthetic oil. Also clean the top of the tranny well. Get the dirt and grass that's caked up in the cooling fins at the top of the tranny to keep it from overheating and cavitating when it gets hot (another possible cause or contributing factor to your problem).

How about a sears model number. Most likely will start with 917.

Thanks! here is my Model # 917.272220

In addition to what Cheese recommends you may need to purge the transaxle. Here is the procedure, straight from the service manual:

PURGING PROCEDURES
Due to the effects air has on efficiency in hydrostatic drive applications, it is critical that it is purged from the system.
These purge procedures should be implemented any time a hydrostatic system has been opened to facilitate maintenance or any additional oil has been added to the system.
Air creates inefficiency because its compression
and expansion rate is higher than that of the oil approved for use in hydrostatic drive systems.
The resulting symptoms in hydrostatic systems may be:

1. Noisy operation.

2. Lack of power or drive after short term operation.

3. High operation temperature and excessive expansion of oil.

Before starting, make sure the transaxle/transmission is at the proper oil level. If it is not, fill to the specifications outlined on Page 9, Figure 4. The following procedures should be performed with the vehicle drive wheels off the ground, then repeated under normal operating conditions.

1. With the bypass valve open and the engine running, slowly move the directional control in both forward and reverse directions (5 or 6 times), as air is purged from the unit, the oil level will drop.

2. With the bypass valve closed and the engine running, slowly move the directional control in both forward and reverse directions (5 to 6 times). Check the oil level, and add oil as required after stopping the engine.

3. It may be necessary to repeat Steps 1 and 2 until all the air is completely purged from the system. When the transaxle moves forward and reverse at normal speed purging is complete.

Thanks Airman,Cheese. It's gotta be low on oil because I've purged a few times. My transaxle is located under my gas tank which is under my seat not under my battery......:thumbup:

Oops...

Most of them have the battery under the seat. With the gas tank there, it will be a bit more tricky to get to the tranny.

Oops...

Most of them have the battery under the seat. With the gas tank there, it will be a bit more tricky to get to the tranny..


Took back plate off. Tranny was right there. Fluid level was fine. I think vent was plugged. Now the mower only goes in reverse no matter if i have the lever forward or back any Idea's?

Check the linkage from the control to the transmission, could be loose, generally if it will go in reverse it should work in forward.

Considering your problem only began after you tipped the mower I feel the problem is caused by something simple.

When a unit only operates in one direction, the service manual says the problem may be:
1. Control linkage bent or out of adjustment
2. Drive belt slipping or pulley damaged

Download these two manuals. There is some information concerning your transaxle in each of these manuals
.
http://www.gardening-tools-direct.co.uk/content/husqwm248_hwen2001_177868.pdf

http://www.gardening-tools-direct.co.uk/content/husqwm247_hwen2000_173750.pdf

The transaxle in your mower is a Hydro-Gear 314-0510. I do not think your problem is internal to the transaxle. If it comes to that and you feel you are capable of the inspection/repair, PM me with an email address and I will send you a document you will need.