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Discussion Starter · #1 ·
Hi,

I need help determining if my solenoid (or starter relay) has gone bad. It is only about 1 1/2 years old. As some of you know I recently upgraded to a 2bbl carburetor on my I6. The engine ran fine before the upgrade, the day of the upgrade and it ran the next morning. By the afternoon the engine would not start. I determined that the carburetor was getting fuel and the battery was replaced when the solenoid was so it should be fine. Several times, while attempting to start the engine the starter became stuck and would not disengage. The engine would not shut off unless I disconnected the negative battery cable from the terminal. Several VMFers said it was probably the solenoid or the ignition switch. I just tested the battery and solenoid with a multimeter and they both tested around 12.47 volts. A good ("good" as in "functional") battery usually measures around 12.5 volts, correct? What voltage does a good solenoid measure? Is my fairly new solenoid dead? ::

Thank you,

Justin ;)
 

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Sounds like the solenoid is bad. Not that expensive
at the auto parts house.

G/L, sparky!!!
 

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Do you hear a click like the solenoid is trying to pick up
when you try start? Then the solenoid may be good but your starter is beginning to give up. If you get no sound at start up( like a dead battery) then its your solenoid and yes new ones can have infant mortality.
 

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By the afternoon the engine would not start
Describe "would not start". Does it turn over, but won't fire, or it doesn't even turn over.

If it turns over, there's probably nothing wrong with the selonoid. If it won't even turn over, I'd check first that the selonoid is well grounded before replacing it. They must be grounded to work.
 

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I would replace the solenoid - the runaway starter is a classic symptom of a bad solenoid. 1.5 years is pretty good for some of the newer stuff. If you get a better solenoid from NAPA (as opposed to the $6 Autozone model) it may last longer.
 

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your solenoid is just a relay that pulls up by 12 Vs from ign switch when put in "START" position. this ties 12vS from battery cable to starter cable at solenoid. that solenoid sometimes sticks and leaves the 12 Vs to starter and grinds away - a rap with hammer usually unsticks it but its hard on starter/flywheel teeth. also it gets sticky and doesn't pull up. to test solenoid take a clip lead (piece of wire) and touch "S" term (one with red/blue) wire on it to battery + term - leave trans in park or neutral and ign switch "OFF". engine should crank. this eliminates ign switch and NS switch if auto, and wiring. i would guess your solenoid is bad and is cheap to replace if you don't want to toy with it. solenoid also puts higher Vs (9 to 10Vs )to coil as long as you have ign switch in "START" to give higher coil voltage - starter drags coil voltage (6 to 9 Vs) down. solenoid voltages are battery voltage on battery side with big cable and starter not engaged, battery voltage less starter drag down (usually 9 to 10 VS) with starter turning) on starter cable, "S" term has 0 Vs until ign key goes to "S" then it goes to battery term voltage (usually 9 to 10 Vs), and "I" term going to coil is 9 to 10 Vs while cranking and then to 7 to 10 Vs aftr engine running (thru ballast or "pink wire" resistor). PM me if question.
 

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Discussion Starter · #8 ·
Describe "would not start". Does it turn over, but won't fire, or it doesn't even turn over.

If it turns over, there's probably nothing wrong with the selonoid. If it won't even turn over, I'd check first that the selonoid is well grounded before replacing it. They must be grounded to work.
Sorry, I should have explained this in more detail. The engine will turn over but it will not fire up. It will just crank indefinitely. I bought a new solenoid from NAPA. I will test the current solenoid tomorrow using BillScott's method. I got some aluminum today and I am going to try to fabricate an air cleaner adapter for the new carburetor. Thanks for the help everyone. ;)
 
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