Starter contacts continuity (1 Viewer)

[Vlex]

Hi all!

I'm rebuilding my starter with new contacts & plunger because of an intermittent no start.
I've changed both contacts per FSM and the plunger.

But when bench testing, it doesn't do anything...

I'm testing with a victron charger set to 12V 15A power supply. PLUS on the battery-terminal on the starter. MINUS on the starter-body. Then checking with a jumper-wire between the small connector on the starter and the PLUS power supply. There is a little spark when testing, but no click or something better.

I double checked all the contacts / insulators and everything looks in order.

When I check the positive terminal on the starer it's properly isolated from the starter-body. But when I check the terminal on the other side (to the starter-motor wire) it has continuity to the starter body? Is this correct?
The continuity comes from the little wire inside the solenoid housing, which is connected with the flat-terminal between the contact and the insulator.

My next step would be to test it on a battery, but first I would like to check that there isn't a short inside the starter.

Hope someone could point me in the right direction. Thanks!

 

[fjbj40]

Use your battery

 

[robnicko]

as above, you need CCA from a battery to trigger the solenoid
also, use a multimeter to check for possible shorts beforehand - no risk that way

 

[Vlex]

as above, you need CCA from a battery to trigger the solenoid
also, use a multimeter to check for possible shorts beforehand - no risk that way

Thanks! Sounds logical.
But I've used a multimeter to check and that's when I found that (strange?) continuity between the starter-motor wire and the starter-body. Or is this normal because its connected to the body through the motor? (but then the insulators wouldn't be needed right?) Can't wrap my brain around this...

In short, is it ok to have continuity between these parts?:

 

[Malleus]

IIRC, you're missing a ground. The solenoid is grounded through the starter motor case. I tried the same thing the first time I rebuilt a starter and never could get the thing to work, separately from the starter motor. As soon as I bolted them together, it worked. I never went back to find out what I needed to do to bench test just the solenoid. I was so frustrated by that time that after it worked I installed it and went on with life.

If I get a chance today, I'll pull a unit I have on my shelf awaiting rebuild and see if I can replicate the circuit for you.

You should be able to get the solenoid to operate with a power supply. The motor needs high amperage to turn the engine; but the service manual test specifies using a battery. I found that odd, since the manuals were written for dealer shops, and they should have power supplies, but whatever.

 

[TheBussman]

normal, if it was open your starter wouldn't do anything. Insulators are needed so that it doesn't short out.

 

[fjbj40]

That’s normal. Remember your consuming power so the - and + have to kiss.

You tried your battery charger with no ill effects, as unit didn’t pop its breaker or smoke, correct?

 

[Vlex]

Allright, thanks everyone!
As some of you have suggested, just test it with a battery and don't overthink it. I've had it tested at the local mechanic, just to be sure, and it works flawlessly. My battery charger probably wasn't strong enough.
Now to get it back into the truck. Thanks again!

 

[Vlex]

It’s back in the truck and all good!

Still strange that I couldn’t trigger the solenoid with a 15A power supply. Ah well!