JD 650 utility tractor starting problems

[maichip]

As stated above, I have a JD 650 utility tractor that fails to start. A little background first: New battery, starter recently rebuilt. The tractor will run perfectly when push started.

When I attempt to start sometimes I get a slight clicking sound at the starter other times, no sound, no start. I have been through unit thoroughly. I attempted to start via disconnecting the neutral, start, main shift switch, and still no go. I do have power to the starter. There is not a whole lot to the electrical system on this unit but I cannot seem to break the code. Is there something I am missing or do you think I may have a short in one of the wires within the harness?:confused2:

Any ideas would be greatly appreciated.

 

[jd110]

Welcome to the forum! Most likely you are having too much voltage drop in the harness to engage the starter solenoid. I have run into this on quite a few of these "50" series tractors(650,750,850,950,1050). Small amounts of corrosion develops at all the connections in the harness from the battery to the fuse panel, keyswitch, neutral switch and starter. The easiest solution is to add a relay in the starter energizing circuit to ensure a full 12 volts gets to the solenoid on the starter. This is much cheaper and easier than replacing the wiring harness.

 

[kebo]

^^^ What he said. There are already several threads on adding the extra relay. I had a JD 750 with the same issue as yours, and after I added the extra relay, it cranked right up after that, EVERY TIME.

Try this for the heck of it..... Keep a small hammer handy. Next time you crank it, and it just clicks, take the hammer and tap the starter a few times going from end to end with the ignition key in the crank position. If it suddenly spins over and cranks up, then you probably need the relay. The relay helps overcome all the voltage drops in the wiring (which is slightly undersized to start with) and the resistance developed over the years from all the connection points (slight amounts of corrosion and oxidation). All that resistance adds up and limits the heavy inrush current needed to make the plunger inside the starter "slam" in real hard to engage the starter motor.

I might see if I can dig up one of those older threads on this.

 

[Brimstone10x]

john deere has a start relay kit ,its made for some of the older lawn tractors but is commonly installed on many tractors , like your 650. dont use a hammer on the starter they cost like 700.$ just use a jumper from the battery cable to the start terminal , if it cranks the stater is good also the battery and cables are good.

 

[maichip]

Thank You for your help. It looks like I will get a relay from my local JD dealer (hope they still have them) and see if that works. I might get a new wiring harness as well, the one in the unit has been cut and spliced so may times over the years, it certainly couldn't hurt to replace it.

Thank TBN for your help:thumbsup:

 

[RoyJackson]

Thank You for your help. It looks like I will get a relay from my local JD dealer (hope they still have them) and see if that works. I might get a new wiring harness as well, the one in the unit has been cut and spliced so may times over the years, it certainly couldn't hurt to replace it.

Thank TBN for your help:thumbsup:

Wiring harness can be an expensive proposition!
While your at the dealer, see if he can get you a service manual (with the wiring schematic).
The 650 is a pretty old machine...good luck!

 

[kebo]

Thank You for your help. It looks like I will get a relay from my local JD dealer (hope they still have them) and see if that works. I might get a new wiring harness as well, the one in the unit has been cut and spliced so may times over the years, it certainly couldn't hurt to replace it.

Thank TBN for your help:thumbsup:

The relay doesn't necessarily have to come from $JD$. There are a lot of 12VDC relays available that will work just as well, it just needs to have at least one NO (normally open) contact with a sufficient current rating.

The relay I used on my old 750 did not come from JD, I got it from an alternator/starter shop. The guy there is actually where I learned about this "trick", and he told me how to wire it up too.

I imagine if you check a local alternator/starter shop, they will know what you're talking about. If not, find another shop!!!

 

[murphy1244]

The hammer trick was a ford starter trick for a bad brush. Don't do that on yours.

 

[Tx Jim]

Here's one for a JD 4020 that will work that you can get from JD dealer. RE170320 KIT, STARTER CIRCUIT RELAY ADD 27.55 USD

 

[California]

Isn't that thing built from Yanmar components of the same era? My YM240 needed minor renovation when I bought it. One item was to replace the key switch (ignition switch) which had become unreliable, intermittent, in the 'Start' position. (I also replaced the clutch safety switch which the previous owner had botched up badly while mis-diagnosing his problem).

You could test for a bad key switch using a jumper direct from the large 12V terminal on the starter to the smaller Start terminal near it, to bypass the ignition switch. Think safety - shifter in neutral and throttle at zero.

If this works then try jumping across the terminals on the back of the ignition switch to see if the intermittent circuit is in your wiring or inside the switch.

I bought a clone replacement switch from hoyetractor.com. When I cut open the old switch I found it stuffed with dead pillbugs.

I don't think Yanmar ever used a relay between the key/ clutch safety switch / pto safety switch / starter - just heavy gauge wire.

Here's the wiring diagram for a Yanmar built around the same time. Its pretty simple. It should give you some idea of what you are looking at.