24V Starter Solenoid Won't Activate

24 Volts starter solenoids will draw heavy currents to operate.

The 24 Volts Power source should have adequate AH (if Battery)capacity to operate the Solenoid.

Is there a loose connection somewhere in the circuit - enough of a connection to register 24VDC on a high-input-resistance device like a multimeter, yet forming a blockage to high currents?

yes, if you are measuring across the coil it sounds like an open circuit within the coil, you measure the potential at across it but no current flows, on the other hand if you are measuring between ground and the +'ve supply then the open circuit would be to ground. It is always difficult to diagnose without full information, or a picture, or knowing what supply you are using or what the application is (a truck starter motor solenoid) or is this a 24V contactor in an industrial control circuit and you have used one with a 240V coil, I've seen that before. This is the best I can do from this end.

BTW what does barely working mean, what are the symptoms, noises, smells etc.

Buzzzzzzzzzzzzzz, engk, buzzzzzzzzzzzzzzzzzzzzzzzzz

In what manner and location are the power cables +/- attached? Is there adequate ground?

Automotive starter solenoids are typically activated by grounding the switch lead that connects the solenoid to the starter switch. The "hot" terminal of the solenoid remains connected to the battery at all times. You probably have a defective or ungrounded starter switch, a loose connection, or a broken wire.

You will also want to verify wether or not it is a 24VAC or 24VDC coil. A 24VAC coil will not work properly if fed with 24VDC.

Shawn

Use a jumper cable from + battery post to + terminal on starter and see if it spins. (be careful)

This will help to know if the problem is else where.

Older starters/solenoids sometimes have lubricant that dries or gets gunky enough to prevent the solenoid from slamming home the bar across the two contacts between the battery and the starter motor windings. Recommend a disassembly, cleaning and lubrication of the solenoid. Check the condition of the shorting bar and the contacts for excessive pitting, corrosion, etc.

ummm, you did check continuity on the coil, right?

Check the ground. Its not jut about the positive. Agree with other posts, check the continuity of the coil.

regards,

Satan

Regards to all !

<< I have a 24v starter solenoid that wont activate....it has consistant 24v at the terminal but no juice. My guess, not enough amps to build a strong enough magnetic field. >>

I assume that:

If the setup is open:

---------------------

1. Guest has direct wires connected between Battery & starter solenoid through a switch or making manually.

2. Has measured voltage with a multimeter; not assumed to be there.

Then the only thing he is ignoring is to check the continuity of the Soleniod.

It should have a small values.

See #1 #3 #10

If the setup is in a vehicle.

-----------------------------

Above points also apply

See #6, #2 & #8 for simple check of automobile wiring.