My friend has a JD315D loader backhoe that was being used and the motor stopped. It was thought it may be a fuel problem with the lift pump being the problem. The fuel system had frequently needed air bleeding and as fuel level dropped the motor would stutter. After sitting for a few days cranking the motor was difficult, ie very slow crank. Batteries were charged but motor would not crank quick enough to start. It was accidentally noticed that if the loader control was operated during cranking the cranking speed increased substantially. Eventually the motor was started using this method the machine was driven into the nearby shed. The motor however was labouring. When the motor was shut down it stopped turning abruptly. Motor will not start without operating a hydraulic function. It felt like there was a hydraulic pump lock up problem. Has anyone had a similar problem or a suggestion as to where to look for the problem.
some have a solenoid on the hyd pump make sure it is working it unloads the pump older ones had a manual valve that you can turn in pump may be bypassing and need rebuilt. most JD owners rock the steering wheel back and forth wile cranking to relief pressure
Dave, are you referring to the closed center, radial piston pump that JD used in lots of equipment? Most of us being Americans, a 315 does not bring a backhoe to mind. This looks like a British version of a 310 with a gear pump system. That would be less likely to load up the engine at idle but possible. I don't know where the steering and brake oil comes from on those. Any of the other drives off the engine could be causing this, from the torque converter to the alternator bearings. Best way to find it is turn the engine by hand, if it's tight, then find it. Remove the belt, remove the hydraulic pump drive, that leaves the torque converter and the engine itself. If the hydraulics load it up as clearly as it seems, the steering and brakes, or the divide between loader and backhoe is where I'd start.
I have seen a stabilizer control sticking in the stabilizer up position.
Yes Dave I am aware of the JD closed centre system used on the JD400A and most agi tractors of the era. However the 315D although build in USA uses a gear pump with an open center system so this doesn't apply.
Interested to hear about the stabilizer valve sticking. How was this rectified? It seems to me that one circuit is in operation and the pump is under pressure causing the starting problem.
I have seen it a couple of times ,one of the stabilizer control valve spools had a slight nick in it so the spool would stick in the stabilizer up position. The customers didn’t want to spend the money so would just nudge the control lever to center the spool manually.
Problem solved. It appears that when the loader backhoe stalled due to lift pump problems the owners son must have placed something hanging on the extender hoe lever. Hence the reason for slow cranking as the hoe was fully extended. When the owner returned from a trip to Melbourne he thought a battery was faulty and he went and purchased 2 new batteries. That didn't help until he saw the item hanging on the extender hoe lever. Removed that and everything works perfectly. An expensive lesson to not let other people use your machines. Thanks for the responses.
That will do it
FYI the Deere 310D and 315D are same except for mainframe with side shift for the 315D. It incorporates mounting for side shift frame assembly for swing frame to enable it to be shifted right or left. Has heavier built stabilizer towers etc. The frame part number is AT170594 if anyone wants to view on Deere parts page. I have seen about 3 of these in my years repairing Deere equipment. Must be still some demand because they offer a 315SL.