I have an '89 1840 with a Sundstran-Sauer M91-46 pump that is leaking. The pump works normally but it is leaking from the gasket that attaches to the rear of the pump engine side. It leaks without pressure and is no worse under pressure. I have rebuild other types of pumps and transmissions but not this one. My question is, anyone have experience with these and are there any common failure issues? Any special tools or info I might need to fix this or is this something I shouldn't do myself?
Most likely cause is a worn seal on the input shaft and possibly a damaged shaft. With the experience you say you have it won't be a problem, they're a simple pump.
Thanks for the input. I have a manual coming Monday. I didn’t think it was anything special just want to make sure. Thanks again.