L48 ignition bypassing glow plug

[ejayb9]

When it turns over in the first position, what happens when you turn the key to second or start position?

My thought on why it will not start is the fuel cut off solenoid is not energized. That normally takes place when key is in start position.

There is no change when I turn it the second position (start position). At least, I can't audibly hear any change. It continues to try to turn over the same as in the first (run) position. And when I flip it back to run- same thing. No audible change or change in firing.

It's a brand new starter. But I did go ahead and order a new one just in case. It will be here Friday. If that doesn't fix it, then I'll have to call someone.

 

[ejayb9]

Just noticed you're in VA - an L48 should start with no help from the glow system - sounds like fuel isn't flowing when it just cranks

Agree with K5lwq - the stop solenoid (part 190 on attached) has to be powered and working for fuel to flow. Try feeling the stop solenoid while somebody turns the key on-off - should be able to detect the click. (stop solenoid withdraws at key-on)

Just ordered a new 190. 1A021-60015. It arrives friday. I'll replace it and the starter on Saturday. Hopefully one of those fixes the problem.

 

[pmmully]

so what happened?

The system appears pretty simple, RUN engages the fuel solenoid to open and the glow plug circuit. Same on my Cummins 210 in the boat. The bit about the starter turning in RUN is the biggest issue to me, that could engage the starter into the flywheel when the engine is running. I think you are lucky that it did not start.

A test light on the leads would sort this out in a hurry, RUN should have power to the fuel solenoid and glow plug relay, but NO power to the starter solenoid. You should be able to hear an audible click when the fuel solenoid engages. When in the START position, there should be power to the starter solenoid and the fuel solenoid while the key is in START mode only, and the power to the starter should stop after releasing the key.

A wiring harness can be hard to diagnose, as a simple jiggle can change the outcome and drive you crazy.

 

[sea2summit]

Have you inspected all the wires between the harness and the glow plugs and starter? Sounds like you could have a rat problem to me. They got my truck bad last year AND I WAS DRIVING IT EVERY DAY!

 

[ejayb9]

Wow! I can't believe after months of not starting it finally started! I went outside and did the regular routine. Key in, clutch in, and turn key to first position. Ignition tries to start. I do my standard yelling and screaming, jump out and walk away. Came back an hour later and looked at the wires coming out of part 190 (stop solenoid). The harness sits lower in the engine in relation to the wire connector on the 190. So, I thought maybe over time, the wires inside might be stressed or the connector might not have a strong hold. So I held up the harness and the thing started normally!

Now I just have to figure out how to rebuild the harness. I saw a price online for a new one was over $600. That's crazy for a few wires and a connector.

Thank you k5lwq and rbargeron for pointing me to the stop solenoid. Never would have figured out it was a bad connection there. Feels good to have figured it out.