Where is the solenoid on a MF245 Diesel ?

Where is the solenoid on a Massey Ferguson 245 Diesel ?

I'm having trouble starting the tractor.

When you turn the ignition, you hear two clicks and the engine will not crank. The battery tests good.

The solenoid should be mounted on top of the starter. Have you checked everything discussed, and the things you checked, last time it wouldn't start? From you post back then it sounds like you wiggled wires and it started. Did you find the cause of that issue and fix it, or has it worked since without doing anything more to it? Just trying to get the whole of the info and conditions on the table.

Jim.ME,

Thanks for the photo.

The two wires attached to the solenoid were removed and cleaned.

That didn't solve the problem.

Turning the ignition switch results in two thunk clicks.

I can't tell if the solenoid or starter is bad.

Some of this is likely overkill and I'm sure others will have different ideas but here is something to start diagnosing with. Please answer questions to avoid guessing or having to ask again. When doing voltage checks report the voltage you read so people can see what you have and offer suggestions. You may need a helper for some of these checks.

This is a diesel, correct? Do you have the correct MF service manual with electrical schematics? Do you have a volt/ohm meter for doing diagnostic checks? How familiar you you with doing electrical trouble shooting? You have had problems before, correct? Have you had the battery tested? What is the battery voltage? Have you ever had the starter tested/rebuilt? Make sure the tractor is in neutral during testing. If you use a booster cable, or other heavy jumper between the big posts on the starter solenoid does the starter spin? Try engaging the switch to start and jumping the big solenoid posts at the same time. If that work to crank the engine over, I would replace the solenoid and see if that solves the problem.

If it doesn t work, start with basics. Regardless of how they look, clean the battery terminals and cable clamps. Next clean the ground connection and cable lug of the negative battery cable. Is it ground to a chassis casting or sheet metal? If connected to sheet metal, move it to a casting. Likewise clean the positive battery cable lug at the starter and check the connector lead going to the starter from the solenoid. At least loosen and tighten the starter solenoid mounting screws and the starter mounting bolts to be sure that path to ground is good, you could remove the starter and clean the mounting surfaces, block and starter, to ensure the ground.

Once all are clean check voltage across the battery posts, then check at the battery terminal of the starter solenoid, ideally it will be very close to the battery voltage if not the same. Check voltage on the battery terminal of the starter solenoid when trying to crank the engine. Voltage should drop some if the starter turns. If it drops and the starter doesn't turn try connecting a good heavy booster cable in parallel between the battery positive and battery terminal on the solenoid. If that works likely the positive cable is bad internally. Try a booster cable in parallel with the battery negative cable to ground to see if that cable is good. Check voltage from the switch when in start position to the neutral start switch. Check for voltage out of the neutral switch when key is in start. Check voltage at the solenoid terminal from the neutral start switch with start switch engaged. Check voltage to the solenoid start terminal to the starter when trying to start it.

Jim.ME,

Thanks for the detailed help.

This is a 1976 MF 245 Diesel and was purchased used so the age of the starter or solenoid are unknown.

I have the operator's manual.

https://agmanuals.com/products/mf-245-tractor

The battery tests over 12v, was successfully charged with a trickle charger and the battery cables and terminals were brushed and cleaned.

I'll trying jumping the solenoid posts and checking voltages today.

The operator's manual has good info on regular maintenance, care of and operating your tractor. For electrical diagrams and more in depth info, diagnostics and repair info the service manual is the one you need. According to AGCO publications the part number for the 245 service manual packet (All the pages, you put them in you own binder) is 1448778M1. It is available assembled but the assembly is over twice the cost. This site's store many have manuals as well.

http://www.agcopubs.com/massey_ferguson/service_manual/english/1448778m1/245_tractor_packet_

You can use the AGCO parts books on line at https://apb.agcocorp.com/

When the two solenoid posts are jumped, there's a spark, but the same "thunk-thunk" sound occurs and the starter does not engage.

The starter might have locked.with the ring gear. Try this, with the key the off position put it in high gear. Grab a rear tire and rock it back and forth a few times. If the starter was stuck it may come free. Put it in neutral and try starting it. Another method is to back the starter mounting bolts out until the starter is loose and can be pulled back a bit, wiggle it around then tighten it up and try it.

Jim.ME,

Thanks for your detailed help.

Replacing the starter was the solution.

The failed starter must be old, because the new replacement model is about 1/3 the weight, less than 1/2 the size, shorter and easier to install.

The engine now cranks on the first try every time.