Jinma 284 will not turn over

First, a diesel doesn't need electricity to start, the switch only energizes the other electrical devices. Compression is what fires the engine off. 

If you jump across the two large solenoid terminals all your doing is making the starter motor rotate. To engage the bendix into the flywheel so the starter motor turns the engine you have to jump a hot wire to the small terminal on the solenoid. If the starter doesn't engage the flywheel and spin the engine your starter is defective.

Since you said when you jumped the terminals and the starter motor spun then that part is working. If when you jump a hot wire to the small stud on the starter solenoid and the starter doesn't turn the engine over and doesn't even spin the starter then you probably have a defective starter solenoid.  

What Carl says is true.

Also, using the correct terminology will help too. There is no ignition system on a diesel engine, hence no ignition switch. It's a key switch.

Make sure all of your electrical connections are good, including the battery posts and chassis ground connection. Make sure the transmission is in neutral, key switch is turned on, and then jump between the large and small terminals on the solenoid. Engine should start.

The reason for the key switch to be on is that there will be field current going to the alternator so it lessens the risk of damaging the voltage regulator.

As an aside, make certain you have the clutch pushed in all the way when you are using the starter switch (there is a safety switch engaged when the clutch is pushed in all the way).  If you using a jumper wire to engage the starter solenoid, make certain you have the transmission in neutral. 

You can remove the solenoid and take it apart. The plunger in the solenoid may be dirty or rusty. Clean the bore and the plunger and put a very thin film of high temp wheel bearing grease on the plunger and in the bore. By thin film I mean it should just feel greasy not look greasy. All you want it for it to move freely and not get corroded or stuck again.

I took my starter apart and cleaned and lubed it shortly after I bought it. The starter was dirty and dry, no lube at all. Yours probably needs the same thing done to it. 

This is where Carl and I disagree.

I say do not use any type of oil or grease in the solenoid motor (yes, that's the technical term for the coil and plunger) for two reasons:

1) Grease, when cold, adds high current draw to the coil because the plunger doesn't move easily

2) We all know that grease and oil attract dust and dirt like a magnet – the last thing you want in your starter

Instead, lubricate the solenoid motor with a graphite solution such as Lock-Eez or any good graphite spray. Your starter will thank you.

There is a small bolt or machine screw on each side holding the “ears” to the starter motor. Remove those after disconnecting the battery cable at the battery post, and disconnect the battery cable at the solenoid along with the small wire. There will be a link and a clevis pin with a cotter pin at the end of the solenoid – remove them and then lift off the solenoid, remove the rubber boot and the motor plunger will come out.

You can also remove the bakelite end by removing all of the nuts on the copper studs to check the relay contacts.

If you are interested, send me a PM with your Email address and I can send you a couple of PDF files.  One is the Starter disassembly and the other is the Solenoid.

My suggestion is that you do both.

RonJ

you might want to review some of the posts on the electrical issues causing starter motor problems.sometimes what you would think is mech. is electrical.

Files have been sent to your Email account.

RonJ

No ignition system on a diesel ? then how does the fuel ignite to operate the engine, you know make the pistons go up and down to create torque and horsepower to get your work done with the tractor.

Compression.

Chichi wrote:

“No ignition system on a diesel ? then how does the fuel ignite to operate the engine, you know make the pistons go up and down to create torque and horsepower to get your work done with the tractor.”

Ahem,

Do you see any spark plugs? Spark plug wires? Distributor? Coil? Carburetor?

It's a compression-ignition engine not a spark-ignition engine.

Time to hit the books and do some Googleing.

Start with Rudolf Diesel.

And George Washington Carver. The early American diesels ran off peanut oil.

I saw a program that said the first diesel engine adolph diesel made ran on coal dust has anyone else saw or read this? I think they showed a picture of it and it was fairly large stationary type single cyl.

That makes sense.  I'm sure that went away for the same reason you don't see anyone using grain dust!

Hey Ron I am not sure how to send a PM to you, but could you send me the starter/solenoid pdf please.  Email is below

Thanks

wvb2020@aol.com