I have a John Deere 310SE Loader backhoe it will not move forward. When you first start the machine it will move forward. It will go in reverse on problem
Welcome to HEF herkjohn ! First thing I would check out if reverse works fine is the FNR switch. If it is sending the necessary voltage to the transmission then pressure checks would be next. Serial number?
Thank you. Serial number 876580. I check the FNR swith it was working. How would I pressure check it.
Is your transmission a sychroshuttle (4 soeed on the floor) or a powershift (speeds on the FNR lever). Your serial indicates synchroshuttle. Did you check it with a voltmeter by carefully backprobing the FNR connector? Did you check voltage at the transmission connector to make sure the voltage is getting to the shift solenoids? Before moving to pressures, are you handy with a multimeter? Remove the 10 amp FNR/Brake fuse and put an amp meter in it's place. Make sure your red lead goes to the fuse's power side, black lead to the load side. Check the amps in neutral park brake on, neutral park brake off, then in forward, then reverse and report.
Sychroshuttle 4 speed on the floor. Yes checked FNR connector. I will check everthing else today thank you very much and have good Memorial Day
Sorry I had go out of town. I Checked neutral solenoid on was 2.42 off was 2.00, forward solenoid move FNR into forward position .60, reverse solenoid move FNR move into reverse position .75, park brake solenoid park switch on .44 then switch off 2.44. Anything else thank you.
Those numbers look about right. Do you have gauges? Now you need to check system pressure and forward clutch pressure. On the transmission control valve there are ports for testing. One labelled "PS" would be for system pressure and "PF" would be for the forward clutch. They both need to be measured with the trans warm, engine at 1600 rpm and checked both in neutral and forward with the floor shifter in neutral. Pressure spec is 230-275 psi. Just so you know, the test ports are metric thread (I use Parker PD357 diagnostic couplers).
No I don't have a the Parker PD357Y do I need two. And two gauges I will have order them I see Ebay has them. Thank you
No you don't. You can check the pressures one at a time. Two would make it easier though.
System Pressure 240, and Forward cluth 0 no pressure
Next check the pressure at port "PM". Measure at 1500 rpm in neutral. With the 4 speed shifter in neutral and machine raised off the ground (for safety), Shift into Forward. Pay close attention to what the gauge does at the moment of the shift and record what the pressure does Does it go from approx 40 psi to 0 then then come up? Does it drop to 0 and stay there? Come back to 40? Not move at all? Do the same with reverse so you know what it is supposed to do since reverse works. Post results.
I cann't get into the PM port to take a test the floor shifter in the way not enough room. Do you now were I can get 45 dergee elbow. I look everywere Thanks
Sorry, forgot about the shifter interference. You will need (1) Parker No. 4M10C80MX elbow and (1) Parker No. PD348 Diagnostic Coupler.
The Parker 4M10C80MX elbow and the Parker PD348 not available.
A general internet search shows me this one is available. It is a 90* elbow with (-4 male JIC) X (M10 X 1) metric thread on the other end. Can be had at most descent hydraulic shops if need be. Hmmmm. When I get to work I'll check the part number on mine. Maybe the manual has a misprint.
I called parker on both so I found a PD342 but not the elbow. Thanks
My coupler has a different number. What I have is in the link below. https://ph.parker.com/us/en/test-port-couplings-diagnostic-up-to-6000-psi-pd-series-nipples/pd34btx
I will order it. Now I just have find and elbow
Still I haven found a elbow that will work.
https://www.parker.com/portal/site/...N&searchbox=4M10C80MX&selectCategory=products
Order the elbow thinks I looked at that one it had Flare end ? Thanks all your help Mike
I haven't received the elbow yet. I call them twice they said it on it way? Is there anything else I can do. You probably have a idea of the problem.
I think on that machine you can put the shifter in neutral and then remove the 2 bolts attaching the shifter from the transmission and then you can install the straight fitting in the test port. You should be able to tell just looking at it if that would work. I just want to confirm the shift solenoids are working properly (post #11) from the PM pressure. Also perform this test while plugged into the forward pack. I know you said "zero psi" but I would like to know if it shows pressure at all during the shift from neutral. I suspect you have a forward clutch piston issue. Also remove and cut open the filter. Is it full of clutch material.
I tried the shifter all ready it don't move enough. The PM pressure never moved of zero psi during the shift from neutral. The forward clutch piston I would have to pull the transmission ? On filter I will give one more day to see if the elbow show up then I will pull the filter and cut it open. Thanks Mike
PM pressure should have been something like 40 psi in neutral. You should see a neutral pressure of 39 to 43 psi at 1500 rpm. When you shift in either direction, the neutral pressure may drop by about 5 psi momentarily and then the modulation and pack pressure should ramp up quickly to 232 to 260 psi. This all should be accomplished in about 2 seconds after the shift is made. So it was zero in neutral and did not move when shifting into either F or R? Or 40 in neutral and dropped to zero when shifting into forward? Reverse? Yes the trans has to come out for clutch repair.
I cut open filter and not bad at all very little shaving and the fluid looked good? the elbow will be here July 19
PM pressure in neutral at 3 psi go to forward 3psi stays the same. Go to reverse 250 psi about 1.5 seconds.
I'm concerned at the 3 psi neutral reading. It is supposed to be 39-43 psi (@ 1500 rpm). When a shift is made that pressure should drop about 5 psi then ramp up to system pressure. If it drops to something less than 39 psi in one direction and not the other and stays low then that indicates clutch pack leakage in the pack it didn't rise in. It can also tell you if the control valve is working electrically. If you have 40 psi in neutral and shift, even with a bad clutch pack, the modulation pressure dropping (any psi) indicates that the solenoids activated and shifted the spools. What psi gauge did you use? If in fact all you have in neutral is 3 psi you may have more than one issue. Low neutral PM pressure is usually an orifice (C2 orifice) that came loose within the control valve allowing excessive leakage to the return circuit keeping the PM neutral pressure low and can sometimes make shifts take a long time. If reverse always shifts within the 2 seconds then the orifice is most likely in place.
This the psi gauge that I have been using. what should I do next I would like talk to on the phone
With those backhoes, I am still skeptical of the electrical function (even though I don't like the PM neutral pressure). That has been 90% of the time the reason for a loss of one clutch issue with those units. Did you test the FNR with a voltmeter? Run a jumper from 12 volts to the forward wire at the FNR to bypass the FNR? One last pressure test. Tee into your transmission oil cooler line (doesn't matter which) behind the grille with a 0-100 psi gauge. You may have to get creative to make the connection because there are no fitting numbers I can give you. You may have to follow the lines from the transmission to the cooler to know which cooler to tee into. Run the machine at idle and at 1500 rpm. Record the cooler pressure in neutral, forward and reverse at both rpm's.
I did the test on FNR forward run the jumper wire nothing. So I checked reverse it worked just to make sure. I will do the cooler today I need one more fitting. Going to check power again to the forward solenoid
No power going to transmission in forward or neutral x54 engine harness to transmission directional control only reverse
So you do not have 12 volts to pin 2 of the X54 connector when in forward? Neutral (pin 3 of X54) only sees 12 volts when the park brake switch is off.
No power to pin 1 of the X54 connector when in forward. No power to pin 3 when park brake switch is off. Power to to pin 2 reverse good.
Check the wiring where it runs over the top (right side) of the transmission control valve. The wires have a nasty habit of laying on the top of the transmission control valve cover bolt and rubbing thru either shorting (which you don't have because the fuse did not blow) or breaking the wires. Also check the connectors X23, pins 9 and 10 as well as connector X25, pins 15 and 16.
Thanks for all your help I find the problem. There were four burned wires they were on the hydraulic line it was hard to get to but its running good. Thanks again Mike