new life for old solenoid

Southern Ray

Well-known Member
The solenoid on my M gave out. It did a lot of clicking but no power to the starter. I priced a new one at O-Reiley over $40.00, and made in China.
I remember old timers talk of taking it apart and turning over the copper disk.
I decided to try it. Found the copper disk in good condition, but the two contacts were badly worn down. I turned them over and with a little JB Weld put them back in.
It works!
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Good for you. That looks an awful lot like the solenoids that Ford used for decades on their cars and trucks back in the 60's and at least 70's. Used to be two models that looked very similar. Both had hot in from battery, hot out to starter drive. One had only one post for a wire to engage the solenoid, but the other had a second post, although I don't recall what it was or for. I remember working in an auto parts store back in the 70's, they used to go for about $5.00. Times have changed?

Anyway, good for you that got working. Where there is a will, they say there is always a way.

Mark
 
second post delivered primary voltage to ignition while cranking...theres actually another type for tractors only that engages when the small post is grounded.
 
Thank you or clearing that up.

His solenoid looks just like one of the two that Ford used back then. From battery in, to starter out, then switched to the small post to engage the plunger. My guess is that he is still using 6 volt system? Possibly 12 volt? I'm curious as to whether or not six volts would work to engage the plunger on one rated at 12 volt? GM used spring loaded solenoids. Never opened a Ford solenoid. Don't know what if anything is under that plunger. But curious as to whether or not 6 volts would work. The mechanics are the same, but what engages the plunger? Spring?

Mark
 
Congrats, its neat when you can fix something yourself and save 40 bucks. Yep often on solenoids or mechanical push start switches the contact washer or contact end posts themselves get burned and pitted and carboned up which wire brushing and/or filing smooth and/or turning over or around will cure.

I agree that looks similar to what I call Ford type solenoids but with ONLY the small S activation coil terminal. The Fords had 2 small terminals S for Solenoid activation and I for ignition which was hot ONLY while cranking which could by pass a ballast resistor. Of course that could still be used on a tractor that didnt have any ballast or by pass by ignoring that I terminal.

best wishes

John T
 
Since its simply passage of current through the coil that creates a magnetic field to pull that plunger down, 6 volts will likely still create a strong enough field to engage it BUT I CANT GUARANTEE THAT it depends on the return spring pressure etc etc. Likewise, if its a 6 volt solenoid and you apply 12 volts you can bet that will engage the plunger and so long as the time period is brief I doubt the extra current will overheat or burn up the coil windings BUT AGAIN NO GUARANTEE. I'm talkin basic theory here and without specific detailed specs and data one just cant say EXACTLY how long or how well these variations will work/last. Its the kind of thing Ive done for years on the farm with no problem but I dont want to be blamed if farmer Billy Bob does it and burns up a solenoid. Being both an engineer and lawyer is a curse sometimes lol lol

Best wishes

John T
 
BTDT too. Just drill out the rivets and when finished put in small screws and nuts. Worked for me and like you felt good to fix it.

Years ago I was stationed in England and I had a friend with a Morris Minor. He said that the switches in the car were like that....you just disassembled them, made the repair and reassembled. Sounds like a plan. But today it's buy cheap and throw away.....I know the solenoid you mentioned isn't cheap but the philosophy is the same.

Mark
 
Typically a 6 volt solenoid, or starter, will work nearly as long, if not longer, than a 12 volt will, when used on a 12 volt system. My go to guy at our local rebuild shop told me this years ago when we had the starter on Dad's 440IC Deere rebuilt. We had taken the starter in to get the start switch replaced and asked him to check out the starter (ie change the brushes, replace the bearings, etc) while he had it. When we picked it up he asked wether we were running it on 12V or 6V as the starter was wound for 6V. At the time Dad had had the machine for nearly 10 years, and it had been converted to 12V long before we got it.

What he told us was the insulation on the 6V windings was heavier than what was on the 12V. As a result it could withstand the lower amperage necessary when running on 12V where a 12V starter didn't have the necessary insulation to handle the higher amperages necessary to run on 6V.

Like I said we were told that probably 10 years ago and Dad had had the machine for several years already at that time. So, right or wrong, a 6 volt starter had worked just fine for us for over 10 years with absolutely no problems, and I'd have to assume that the coil on a solenoid would do just the same. The only thing is that with 12V to a 6V widning, it would tend to pull in harder, which may or may not shorten it's life.
 
Similar, Ive ran 6 volt starters at 12 volts on plenty tractors over the years (farmer and tractor dealer) and never had any problems either. It can be a bit tough on starter drives and teeth etc since it does kick in pretty hard. Its one application where perhaps you dont want the big heavy honkin battery and cables which can help with the above potential problem as it always turns over plenty fast anwway.... Another problem is if its a magneto ignition with 12 on a 6 volt starter she may spin so fast the mags impulse assembly becomes disabled n shes trying to start at the advanced run timing woooooooo hoooooooo that may be 25 BTDC versus the typical TDC used at cranking/starting speeds lol

Ive never had solenoid problems either but dont want to be responsible if farmer Billy Bob burns something up grrrrrrrrr

Fun chat

John T
 
Appreciate the kind remarks.
It's just a simple solenoid that one of the previous owners installed. It's not original equipment.
I am running 12 volts through it. The small terminal is for the coil. The back side of the coil is grounded.
 
Thanks fellas for the info.

I have an old AC-B that I use for mowing, 6 volt. I've been wanting to convert to 12 volt, but the only thing that I've been concerned with was the starter. Needing to get the coils around the armature rewound for 12 volt, but sounds like a non-issue.

Mark
 

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