Starter Solenoid difference

Kdancy

Thought I'd post this for others info. I was having trouble with a new starter solenoid working. When I applied power to the center post nothing would happen. I ran across this post and tested the solenoid as described and found that I needed a "ground" style switch and not a "hot" style switch.

Starter Solenoids

 the two common 6v types with the single post on the front.
it is easy to tell with an ohm meter or powered test light.

(1)         Continuity between the center post and one of the side terminals is the Ford type that uses a ground for the starter button.

 2)  Continuity between the center post and the mounting bracket uses a HOT starter button. (this is what Hudson used, so I just re-wired the push button switch for "ground" operation by running the center post wire to one side of the switch and a ground wire to the other side. It works fine now.)

Kdancy

more explanation-

Starter Solenoids Two types switched

I was just referring to the two common 6v types with the single post on the front.
Vic, it is easy to tell with an ohm meter or powered test light.

(1)      Continuity between the center post and one of the side terminals is the Ford type that uses a ground for the starter button.

(solenoid center post wire to push button start switch, then out of switch to ground)

 (2)  Continuity between the center post and the mounting bracket uses a HOT starter button. 

(Hot wire from key switch “key on source” to solenoid center post )  or in the case of using a separate start button like pre 52 stepdown, run from “key on” wire to starter button, then to starter solenoid center post.

Jon B

You may have supplied the answer to the question I recently posted, asking why the 1940 8-cylinder starter and solenoid was not interchangeable with any other Hudson starters (in the Hudson interchange manual).

From what you say, the 1940 starter solenoid was possibly of the "hot" style, and all the other years (1937 through 1947, for example) were of the "ground" style? 

I know that on my 1937, the starter switch (when depressed) sends current to the top terminal on the starter solenoid.  In contrast, are you saying that the 1940 starter button merely grounded the starting circuit when depressed?

Nowhere can I find a 1940 wiring diagram to verify this.  The one in the online library's 1940 shop manual, is missing part of the image where the starter switch should be, so I cannot tell if the starter switch is grounded.

Could I merely install my old 1937 solenoid on the 1940 starter?  The 1937 solenoid would be activated by current coming from the starter switch (as it is, now).  And presumably it would direct power to the starter.

In other words, it would appear that it's only the solenoid that's different for 1940.  The 1940 starter itself works just like a '37, '38, '39, and '41 - '47 starter.

Am I correctly understanding that, from what you say?

Kdancy

Im not sure about the years difference. A test on the solenoid like the one described, will show which version you have. It helped me with the 51 pacemaker I am working on. The factory set up was the "hot" type, as shown in the factory wiring diagram and that is how I had it wired, but the new solenoid, when tested, showed that it is the "ground" version. These are easier to get as many Fords and tractors used them. I just re-run the switch wiring for "ground" circuit and it now works.

Jon B

I think you're saying that it all depends upon whether you have a "ground-type" or a "hot-type" solenoid in your hands.  If I read you correctly, you can install either type.  Then, depending upon which type it is, you either wire the circuit at the starter switch 1). so that it goes to ground when pushed, or 2). supplies current to the solenoid when pushed.  

(Again, if I understand this correctly) the starter itself isn't a consideration.  Either type of solenoid can be used.  Whether the starter "starts" depends only upon matching the solenoid to the method of wiring the starter button.

Kdancy

Yes, you have assumed correctly!