What in the world did I do?
The Merc is a 1951 stock 6 volt pos ground.Last year I pushed the button and it started and I drove it 200 feet.
To make things better I "bright and shined" all the connections and replaced both battery cables,starter cable,and bonded the engine block to the firewall.The 6 volt relay was new 10 years ago and only used a few times.
I switched the leads on the relay and it still cranks over.
I've got the white ammeter wire on the same relay terminal as the neg battery cable.
I never turned on the ignition switch as I didn't want it to start.
Can the relay be stuck closed?Do I hit it with a wrench?
Any and all opinions would be greatly apperciated in helping sort this out.This rookie is at a loss.
Cheers to all!

 

Could be several things. Bad ignition switch, bad button, or bad solenoid. Or, something is mis-wired. You'll just have to work backward until you find the problem. Best to do it with an ohmeter rather than the starter. Be careful you don't hurt something.

 

The first thing that came to mind is your starter button is stuck and it is wired hot.

 

I could start with ohming the relay.I would think it would be normally open.If it's closed would that indicate the relay is faulty?
The starter button would be the next ohm check.I "seems" to be working OK.
How do I know if my ignition switch is wired hot?
I'm convinced after triple checking-twice-that I reconected everything the way it was and like the manual says.

 

Sounds like the solenoid to me

 

the simple relay test would be to disconnect the wire from the small terminal of the solenoid leaving it empty and touch the cables to the battery. If it cranks over, bad solenoid. If it does not crank over with the battery connected, there is a short to ground in the starter wire or button.

 

The first thing that you need to do is to disconnect the cable to the starter. With that done you can now energize the system and go through it systematically to isolate the problem without worrying about the engine turning over. Get a voltmeter on the starter cable and verify that there is voltage present. Go back to the solenoid and check the two wires that actuate the solenoid. If there is voltage present then you will have to go a bit further down the circuit; however, if there is no voltage on the terminals and you can remove the leads without causing the voltage to drop on the starter cable, then you know that the solenoid is stuck. Good luck...

 

The Stock solenoid on these old trucks is a 3 terminal (2 large, 1 small) setup. after about '56, they are the 4 terminal (2 large, 2 small) type, and the starter circuit is totally different. the starter circuit does not go thru the ignition switch on these old trucks thru '55 or '56. The wire from the small terminal of the solenoid runs to the starter button, and from there to ground. You are grounding the small terminal of the solenoid to send juice to the starter. This wire is always live. Again, it goes nowhere near the ignition switch. All the ignition switch does is give power to the accessories, and to the coil.

 

Thanks Everyone,
The DW has me busy for the day.
I'll post what I find out.
Thanks again

 

I ohmed this and ohmed that,checked all the issues that were suggested and all looked ok.
Reconnected everything as it was and all appears ok!!!
It does not try to start when battery is connected!
I did wiggle the cable to the starter.It's new.Is there a fibre washer on the starter stud that may be at fault?

 

I hate it when that happens! But it does sound like you have a sticky solenoid...

 

This diagram has the -6vdc from the battery connected to the positive (+) terminal on the coil through the ignition switch. Can that be correct? I have seen other diagrams that have that terminal on the ignition switch connected to the negative (-) terminal on the coil. Which is correct?

 

JRJ, you are correct. It is not correct in the starter button area either, at least for '52-'54, which used a two-wire button.

 

It's all "Julie's" fault. S/He created and posted that diagram. never noticed the coil being reversed, but with a 2 lead starter button, unless you have the 4 terminal Solenoid the second wire from the starter button will go to ground anywho.

 

I'm surprised that "Julius" didn't catch the error in this recent post.