solenoid help

[kenbob]

My 300 has been converted to 12v . Previous owner says both starter and generator, but who knows for sure on the starter. I know the gen is 12v pos. Solenoid had a stripped terminal. I ordered a 3 pole online, and put it in. After starting it a couple times, today the solenoid kept the starter engaged while the tractor was running. My tractor is a bit loud and I had noise suppressors on so I couldn't tell it had not disengaged. Tractor died because I think it wore the battery down. The starter and solenoid were blazing hot. I charged the battery, took the starter off to bench test, put it all together and the same thing happened. I only have a 3 pole solenoid so no possibility of messing up the small wire. I thought the big posts were omni-directional as there is no marking for + -. Am I right on this. IS there any other thing I could be doing wrong except for a bad solenoid right out of the box? IF the starter is still 6v and I put a 12v solenoid on it, would that be the problem. Thanks all in advance. It is still pos ground if it matters.

 

[nick831]

First off yes, you need to have the right voltage solenoid. Six volt solenoid in a 12 volt system will over heat and weld together or just quit working 12 v solenoid on 6 v system will not have enough voltage and will not pull in all the time or only partially in, again burnt contacts or failure. 3 pole solenoid is fine, I prefer a 100 percent duty solenoid as they can handle loads for long periods. They also must be bolted down and grounded well as the body of the solenoid is how it grounds with a three terminal solenoid. It sounds like your solenoid is welded together making contact all the time or stuck. You can check it with an ohms meter across the two large terminals. One from battery the other to the starter. There should be no voltage except when you apply voltage to the small center terminal. Make sure the body of the solenoid is grounded with whatever source you will be using as a bench test. essentially if you pull the solenoid off and just use an ohms meter across the two large terminals there should be no voltage. If there is, bad solenoid. Hope this helps. Nick

 

[used red MN]

Your problem is cheaply built replacement parts. I have heard of this a few times lately on the forum that people have replaced a solenoid only to have it malfunction almost immediately in this way. Some how the contact material is such that it ..welds.. the contacts together keeping the starter engaged. It ..used to be.. that NAPA sold a little higher quality of parts, which you also paid for. I would recommend trying the one in the link to see if it works.
NAPA starter solenoid

 

[kenbob]

Thanks, all. I have a Napa Eschlin one to put in now. I hope this will do better than the last one.

 

[DKase]

100% duty cycle solenoid on a starter will not work. I use them for cab relays so the entire tractor is dead when the key is off. The heaviest I have been able to find is 50 amp. A starter pulls hundreds of amps and will weld the 100% duty cycle solenoid together.

 

[nick831]

Hmm. I have used 300amp continuous duty solenoids used in commercial applications and golf carts. Have always worked great for me.

 

[nick831]

Dkase you are correct in the 50 amp. Since I found the high amp 300s they have worked flawlessly. I actually stumbled across them repairing a floor scrubber and a golf cart for a friend. I have had terrible luck with starter relays from some auto parts, they are cheap and made overseas This has seemed to fit the bill for me. I appreciate your info. If it wasn't for you long time Case guys my 830 would not be working as well as it is now or maybe not at all. Thanks

 

[r.w.b.]

you must use a solinoid thats correct voltage.
get a heavy duty 1 too