ataboy9026

My shut off wont open on its own. I cleaned my terminals at battery and that worked for a few days, now I have to "help" it up with my key on to start my truck. I have a new contact kit for my starter from Fix-in-rams but I was wondering if I could just wire up a switch temporary and use it for a couple days. I could just switch it on with full 12 volt power ( I assume it isn't getting enough thru starter contacts) to open solenoid and then shut off while driving and then truck will shut off like normal with key. I have driven it a few times but its a pain to get out and "help" up the plunger every time. Any thoughts?

infidel

Don't see why not. I would use a momentary contact switch so you don't forget and leave the switch on.
This is what burns up solenoids.

kandgo

Good advice from Bill, also not a bad idea to put the momentary switch out of sight and use it as a theft preventive??? Goodluck,,Rick

kerryneb

The fuel shut off solenoid has 2 sets of coils... pull in, and hold in. The pull in coil is activated by a relay when the key is in the crank position. There's a (blue i think) wire coming from the battery which has a fusible link that supplys power for the pull in circuit via the power distribution center. The terminal on mine was corroded at the battery. I also had to 'help' the solenoid until i discovered the problem.

redramnc

The pull-in relay may be bad - the starter contacts can cause the same problem but check the relay first. If you have power to the feed side of the relay then the fusible link is good. Check to see if there is power getting to the relay energize wire from the starter when it is engaged. I used a short jumper to activate the pull-in solenoid across the unplugged connector while I was troubleshooting mine last time. The relays will eventually fail regardless of the condition of the starter contacts.

infidel

A problem many run into when trying to diagnose shutdown solenoid problems is a voltmeter or test light will often give you the wrong answer. Voltage may read normal but poor connections/relay contacts don't allow enough current to get though. The lift up coil draws a lot of juice. This is one reason the solenoid often gets replaced needlessly, people see correct voltage right at the solenoid but no lift up and figure the solenoid is toast when in fact it is perfectly fine.

Good comparison is the sprinkler in my yard won't turn but there is water coming out. Replaced the sprinkler only to find the real problem was a kink in the hose.

redramnc

Good point, Bill.

Bad contacts can cause alot of head scratching unless you look for voltage drop or actual amperes going through the connection. A jumper wire (I made mine from a short piece of 10ga solid house wire) from the supply wire to the solenoid wire at the relay connector will diagnose the solenoid. If there is voltage being supplied to turn on the relay coming from the starter circuit and the solenoid pulls up when jumpered then it leaves the relay as the culprit.

I have seen a few relay plugs (not on our trucks yet) where the plastic connector body was melted from a high resistance (corroded) connection but still pulled enough current to work properly. Those are the easy ones to find and fix.

It also helps to have multiple DMMs hooked up looking at volts and amps simultaneously when necessary, too.

durasmack

Semi-off topic, but does white smoke coming out of the solenoid body typically mean one of the coils burnt up? This happened to me last night.... once the solenoid cooled off enough that i could push it open, it would hold, but will not open on its own. I will not buy a new solenoid for it if its bad, but if there is anything else to check first i will..... also, are these solenoids rebuildable? i havent pulled it apart yet to look at it, i just know the solenoid was spewing white smoke and internals last night ...

Also guessing maybe relay is bad, caused pull coil to stay hot too long, overheat, and burn out?

Just a note: problem first occured on while attempting to turn the truck off.... it ran without key in for a few minutes then eventually shut itself off....

-Trey

infidel

If smoke came out of it the solenoid is probably finished.
Your starter contacts are likely shot also and are what caused the lift up coil of the solenoid to stay on and overheat.
If I ever had to replace a solenoid I'd just forget it entirely and install a choke type cable shutdown.

durasmack

Solenoid gone, stop cable installed. works fine as of right now.

-Trey

infidel

Good!
Now replace your starter contacts ASAP before you burn up wiring when the starter sticks on again.