Shorted SOMETHING out on Mark 58ae

[threedeesmax]

I've been working on my motor for about two weeks on and off, and at this point I'm about an inch away from torching the &#^$ thing.

I've kitted and refurbed just about everything on the old motor. Today I had it ready to start.

I didn't have anybody helping me, and I wanted to use the choke. Unfortunately, the choke button on my controls doesn't work, and I couldn't be back at the motor and up at the controls at the same time.

So I looked around for something to hold the choke closed. I had the cowl off of the motor. I found a small crescent wrench and adjusted it to hold the choke closed, and then went forward to the controls to turn the key to 'start.'

Great %&^ idea. The motor cranked over a couple of times, and then the crescent wrench fell over against one of the terminals on the solenoid - the one that goes from the solenoid to the starter.

As soon as the wrench touched the solenoid terminal, the starter came to an abrupt stop. It won't crank over now.

How the $%$% do I figure out what I did to it? I have NO electrical knowledge or test equipment - I'm doing this on a shoestring budget.

Where's that charcoal lighter fluid...

 

[emckelvy]

Re: Shorted SOMETHING out on Mark 58ae

Sears has an autoranging digital meter for $14.99 on sale, I'd highly recommend picking up this very basic piece of test gear. Ain't nuttin' on your Mark electrical that couldn't be tested with that meter!

Your solenoid has 2 small terminals; one is +12V and the other goes to ground. Check all the wiring to the solenoid to ensure the connections are tight. Lots of times when you have a high-current situation, a loose/poor connection will arc and lose its electrical continuity.

Very typical for this to happen on the battery posts so it might not be a bad idea to check those, too.

With the battery connected, you should have a constant +12V to ground on the battery side main terminal of the solenoid. Placing the ign switch to "START" supplies voltage to the solenoid coil to make it operate and close the main contacts, energizing the starter.

If you can't make the solenoid "click" when you apply 12V to the small terminal, it's shot and needs replacing. You can even use a battery charger to do this; neg lead of the charger to the small ground terminal on the solenoid and pos lead to the small +12V terminal.

If you can make the solenoid click, with a voltmeter or test lite connected to the starter-side of the solenoid, place the ign to "START" and check for power to the starter. If you're getting power and the starter won't run, problem's inside and likely a brush.

You can also "jump" the solenoid or hook a battery directly to the starter with jumper cables, just watch out for the pesky sparks!

More likely I bet you've got a wire loose/burnt so check all connections and see what happens. BTW you can pick up a test lite real cheap at just about any auto parts store, and that too will work for diagnosing this problem.

Check out a wiring diagram for your motor here:

http://www.maxrules.com/oldmercs/Wiring/0_1965a/4.pdf

HTH & G'luck........ed

 

[threedeesmax]

Re: Shorted SOMETHING out on Mark 58ae

Thank you, and I'll buy that piece of equipment. Sounds ideal for what I need to do.

I'll check all connections in the morning. I just needed to vent, and to get away from the motor for awhile.

 

[Scaaty]

Re: Shorted SOMETHING out on Mark 58ae

Don't give up..have a beer..Ed (above advise) is a wizz with those old Mercs, and that 58 is a classic gem. No high class black boxes we are dealing with here. Calm down and do a complete check of solid (like in not burnt) wires..(and don't ask me about where crescent wrenches belong.. )​

 

[threedeesmax]

Success!

Success!

After sleeping on it, I went out and checked all the wiring connections, and tightened them up. Success! It cranks just fine, again. Thanks to all for your assistance. Hopefully I can get it to start today.

 

[Scaaty]

Re: Shorted SOMETHING out on Mark 58ae

See...!! Good luck with it..