John Deere 2640 - Starter Relay Location?

[Almonzo]

Anyone else have a JD 2640 and know where the starter relay is actually located? I have the tech manual, but the one pic it has for this is grainy and has an arrow pointing to (upper corner under the right cowl) what I've confirmed is actually the voltage regulator (which is square -- the relay is round). I've looked all around under both left and right cowls, under the gauge panel, around the battery area, etc., and just do not see it.

I'm suspecting the starter relay needs replaced, because I get no panel lights, no sound, when turning the key in the ignition. Even if the starter relay is not at fault, locating it would provide a helpful place to connect my volt meter, to troubleshoot what is happening.

Should mention: battery is good, has new ignition switch, have tried gear selector in both park and neutral (no gear) positions. In hindsight, i have seen this issue a few other times, but it seemed to resolve itself eventually.

Appreciate any ideas or info.

 

[Tx Jim]

JD 2640 didn't come from factory with a starter relay. If your tractor has a starter relay it was labeled by JD as field installed. My 1st suggestion is to relocate factory installed battery ground cable from ""rusty battery box"" to starter mounting bolt or at least attach to engine block. Next I would recommend checking operation of neutral start switch although inoperable NS switch would not cause dash(panel) lights to not illuminate.

I served as a JD dealer service manger for 13 yrs when your tractor was brand new.

 

[Almonzo]

Thank you -- had no idea starter relay was optional (another item I wish were mentioned in the service manual)

I confirmed the negative batter cable is running to the engine block. I will check the neutral start switch, though may not be until this weekend.

There also is a circuit breaker, which I believe is self-resetting. The rotary switch for lighting options (headlights, flashers, etc., looks like seen better days (the white coil of wire across two terminals which I believe is a resistor looks pretty fragile).

> I served as a JD dealer service manger for 13 yrs when your tractor was brand new.
That's great -- that's about how old I was when that tractor was new.

 

[Tx Jim]

I've witnessed battery cables that appeared good but had corrosion under insulation. This corrosion limited good amperage conductivity. I suggest to check volts when attempting to start engine

 

[rScotty]

Anyone else have a JD 2640 and know where the starter relay is actually located? I have the tech manual, but the one pic it has for this is grainy and has an arrow pointing to (upper corner under the right cowl) what I've confirmed is actually the voltage regulator (which is square -- the relay is round). I've looked all around under both left and right cowls, under the gauge panel, around the battery area, etc., and just do not see it.

I'm suspecting the starter relay needs replaced, because I get no panel lights, no sound, when turning the key in the ignition. Even if the starter relay is not at fault, locating it would provide a helpful place to connect my volt meter, to troubleshoot what is happening.

Should mention: battery is good, has new ignition switch, have tried gear selector in both park and neutral (no gear) positions. In hindsight, i have seen this issue a few other times, but it seemed to resolve itself eventually.

Appreciate any ideas or info.

Very few machines of any kind now have a remote starter relay. That went out of use decades ago. A remote relay closes by switched trigger current or sometimes manually to provide high amp current to the starter motor. Most cars, trucks, and tractors since the mid 1950s have the starter relay built into a small cannister bolted to the side of the starter motor where the combination of starter relay and starter pinion yoke is now called the "starter solenoid"

How it works is the ignition switch feeds power to the starter solenoid which is an electromagent pulling on a plunger. You should hear the clack as it actuates. When it actuates it does two things at once. It closes the high current path to the starter motor so that it can begin to turn, and it releases or forces the starter motor pinion gear to engage with the flywheel so that the spinning starter motor can turn the main engine.

Back to what Jim said, there were a few MANUAL starter assemblies on machinery 50 years ago. On some of those, instead of an ignition switch powering an electromagnet they had a long rod which the operator moved via a lever. He pushed that lever which closed the circuit and engaged the pinion gear. But that was a long time ago and far away....... and in a land where they also had a remote starter relay that was often on the floor and looked like a dimmer switch.... Your JD 2540 is more modern.

If your starter solenoid is making a clacking sound when you try to start but nothing more happens - and you KNOW that the battery and connections are good - you should be able to bypass the solenoid with a jumper cable from the hot side of the battery and cause the starter to turn. If the starter turns, either the solenoid or ignition switch or fuse is bad.
But it is usually the battery or cables & connectors. I've also seen internally corroded battery cables.
Goodluck,
rScotty

 

[Zebrafive]

I would start at the circuit breaker and see if you have power to it, then through it.
The resister on the light switch is for less voltage to the headlights when in low beam.

 

[Tx Jim]

Very few machines of any kind now have a remote starter relay.


rScotty

I beg to differ with you. A lot of tractors have starter relays even a JD310SG. JD began installing starter relays in 1969 on 3020 & 4020's

& I think you'll perform some research you'll determine tractors built today have starter relays

 

[Almonzo]

I've witnessed battery cables that appeared good but had corrosion under insulation. This corrosion limited good amperage conductivity. I suggest to check volts when attempting to start engine

Thanks -- I don't get any activity though prior to starting attempt either. So glow plugs light never comes on, nor any other panel lights. Yet battery voltage is 13+ (good idea though to monitor voltage the whole time -- I'll give that a try).

 

[Almonzo]

I would start at the circuit breaker and see if you have power to it, then through it.
The resister on the light switch is for less voltage to the headlights when in low beam.

Will do, and resistor makes sense on low beam. Thanks!

 

[Almonzo]

Very few machines of any kind now have a remote starter relay. That went out of use decades ago. A remote relay closes by switched trigger current or sometimes manually to provide high amp current to the starter motor. Most cars, trucks, and tractors since the mid 1950s have the starter relay built into a small cannister bolted to the side of the starter motor where the combination of starter relay and starter pinion yoke is now called the "starter solenoid"

How it works is the ignition switch feeds power to the starter solenoid which is an electromagent pulling on a plunger. You should hear the clack as it actuates. When it actuates it does two things at once. It closes the high current path to the starter motor so that it can begin to turn, and it releases or forces the starter motor pinion gear to engage with the flywheel so that the spinning starter motor can turn the main engine.

Back to what Jim said, there were a few MANUAL starter assemblies on machinery 50 years ago. On some of those, instead of an ignition switch powering an electromagnet they had a long rod which the operator moved via a lever. He pushed that lever which closed the circuit and engaged the pinion gear. But that was a long time ago and far away....... and in a land where they also had a remote starter relay that was often on the floor and looked like a dimmer switch.... Your JD 2540 is more modern.

If your starter solenoid is making a clacking sound when you try to start but nothing more happens - and you KNOW that the battery and connections are good - you should be able to bypass the solenoid with a jumper cable from the hot side of the battery and cause the starter to turn. If the starter turns, either the solenoid or ignition switch or fuse is bad.
But it is usually the battery or cables & connectors. I've also seen internally corroded battery cables.
Goodluck,
rScotty

I do know my 2640 has a solenoid mounted on the starter motor (just above it) -- was going to bypass it except the + side had a shield which required partial dismantling to access.