defed 0 #1 Posted December 13, 2009 is there any benefit to opening the tow valve when starting a D? i noticed that it TRIES to start pretty easily, but takes alot of 'almost' starts before it will finally STAY running. it's like the engine would start unloaded, but the heavy load of the pump kills it. just not sure how the pump moves (or doesn't move) the oil when in tow mode. seems that in tow mode it would just bypass the oil inside the pump instead of moving it thru the system. i know on the belt drive hydros, you can disengage the belt to let the engine get running before you start pumping oil. Share this post Link to post Share on other sites
wh500special 2,267 #2 Posted December 13, 2009 I think any help opening the tow valve would offer would be minimal. The bypass loop created by the valve is actually on the motor side of the system (even though the pump and motor are divorced on the D) and you'd gain little b y having it open. When the pump is turning, the charge pump inside the pump portion of the hydro is trying to ciculate fluid within the hydro pump section. The hydro pump itself when in neutral shouldn't be moving ANY fluid around. So the resistance comes almost exclusively from the charge pump. I think you're stuck. But you might get some benefits from doing a complete tuneup and carburator overhaul of the tractor's engine. Putting it in top condition might make things a little easier on you. Also might be a good time to give it a transaxle fluid and filter change. If you continue to run into trouble, you might try placing a magnetic heater on the differential housing and perhaps even on the pump itself. I never had any trouble starting my D's in the winter, but I understand how a stubborn, stumbling, cold engine might labor to stay running with the hydraulic load applied. Steve Share this post Link to post Share on other sites
