450c won't turn off

[Rincon]

Thanks for your guidance Jim. By eliminating the regulator is it disconnected or does it simply mean that it takes over? On your second paragraph about solenoid, is this the fuel solenoid?. So I have three wires coming into the alternator. A green spade terminal which is 12v when ignition is on not started. A larger red wire which is not hot when ignition is on, I was assuming this should be hot going to the b+. And a little bit smaller wire that went to the d+ on old alternator. On the alternator i was going to replace have on now has 3 connectors , a spade W, B+ and a D+. When I ordered it was supposed match for a 450c. So hooked up, the alternator puts out like 30 volts on the b+ and a little less on the d+. Could this be a 24 volt alternator they sold me?. I'm thinking it is. This could be my problem not shutting off? After I put IT on I never voltage checked it. Paid 115 for it eBay. Jensales has a OEM replacement for 450c 12v Motorola 225$ your thoughts. I will be out for a week before I get back on it. I will keep you posted. Thanks.

[Jim B]

When installing a Delco type (I say type as many "Delco 10SI alternators" sold now are aftermarket copies, not true Delco Remy products. And Delco never made a 1-wire alternator, those are all aftermarket products.) Eliminate means the old external regulator goes away. All the wiring related to it can go away as well and run new wires.

The fuel pump solenoid is inside the injection pump and controls the fuel supply to run or stop the engine depending on the ignition switch position.

I don't have a wiring diagram for your 450C and won't speculate on wire colors and the function those wires carry.

Likewise on the alternator you received. Without info like brand and part number, I can only speculate. Maybe it is 24 volts, I can't say. I doubt even if it was that would keep it from shutting off, I would quicker think it would have burnt the fuel solenoid, up from over voltage, and cause it to fail and the engine to stop.

The correct replacement Motorola alternator should be a plug and play as far as the wires go, if they were in the correct places to begin with. At least they were on any I replaced. I see the JD parts catalog shows a serial number break and two different alternators, and regulators, based on that break. Did you use the alternator numbers on your old alternator to order the new one? Serial number 343540 and before calls out one alternator, 343541 and after is another. Without more digging I cannot say they won't both end up as the same replacement in the aftermarket.

If I get some time I will see if I can relate the wires on one of our tractors, with a Motorola still on it, to what you posted.

[Rincon]

Turns out it was a 24 volt alternator. Re replaced with the Motorola. All good for now. Yes plug and play like 24volt alternator I got the first time. Lol. I think I will also need to change regulator someway somehow in the near future.