Electric Log Splitter oil seal failure

I have an electric, 7 ton, firewood splitter I purchased from Sears mail order January 2015, 5 years ago. It is a Powerhouse model LS7T-52 Log Splitter.



Problem –

The splitting hammer stopped advancing and then oil began seeping from the motor on/off switch that is located on the side of the motor.



Solution –

I disassembled the hydraulic pump from the motor and observed the seal in the pump that seals the hydraulic fluid in the pump failed, allowing fluid to seep between the motor shaft and the seal into the motor and then into the on/off switch box and from there to the floor.



The parts breakdown diagram in the Operation Manual did not show this seal. I was able to read some numbers on the seal, although I did not recognize the numbers as a part number for a time. The seal was 1.024 in outside diameter and the motor shaft diameter was 0.432 inches. On the seal were the numbers 11 at the 9 o’clock position, then 26 at the 6 o’clock position and 7 at the 3 o’clock position. I now know these values are the metric millimeter measurements of the seal. 11 millimeters is the shaft diameter, 26 millimeters is the outside measurement and 7 millimeters is the width of the seal. 



I was able to order this sized from ebay for $5.99 that includes shipping cost and was able to get the seal in 3 days.



I replaced the seal and reassemble the hardware but the motor would not start until I hand spun the motor several turns. Something had to seat apparently as the shaft turned easily after the couple of turns. Then the motor started normally.



I also found some less viscosity hydraulic fluid which was 20 weight which is much closer to the 22 weight the operators manual calls for. (It is possible the fluid I added before was 30 weight which could have contributed to the failure, I suppose. However the reason I had needed to add fluid was likely because the seal was seeping.)