Solenoid Valve Coil

FridayParts stocks replacement solenoid valve coils for the hydraulic valves on skid steers, excavators, tractors, telehandlers, scissor lifts, and boom lifts. We carry 10–24 V DC coils with spade, pin, and lead-wire connections, in 1/2" and 5/8" bores. The fastest way to find a match is to use the part number on your old coil.

What It Does, and Why It Fails First

A coil is an electromagnet. When it's energized, it pulls the plunger and shifts the solenoid valve. The coil usually fails before the valve does, for one of three reasons:

Heat. A coil that stays energized in a hot engine bay runs close to the limit of its insulation.
Water. Moisture gets in through a cracked or perished connector seal.
Contamination. A plunger or spool stuck in dirty oil won't shift, however good the coil is. The coil gets blamed and replaced, and the new one doesn't fix the problem either. Clean or replace the cartridge before you condemn the coil.

What Has to Match

Voltage. 12 V and 24 V coils aren't interchangeable. Some 12 V machines use 10 V coils, so the valve still shifts when system voltage sags. Replace like with like.
Wattage. This sets the force available and the current the controller expects.
On/off or proportional. Proportional coils are driven by the controller's PWM output and matched to it. They won't swap with on/off coils, even when they fit the stem.
Connection. DIN 43650, Deutsch DT04-2P, Weatherpack, Metri-Pack, dual spade, dual lead wires or single lead.
Bore. The coil slides over the stem tube, so its bore must match the valve.
Coil size or series. Each valve maker sizes its coils to its own cartridge range. Check the maker's coil code or part number, not just the bore.

Coils on mobile equipment run on 12 V or 24 V DC, powered by the machine's own electrical system. AC coils are used on stationary industrial equipment, not on machines like these.

Part numbers change. Some valve makers have renumbered their coils. HydraForce coils, for example, now also carry Bosch Rexroth numbers. Your old coil may show either number, so search for both.

FAQ

Can I replace only the coil and keep the valve body?

Yes — as long as voltage, wattage, connection, bore, and stem series all match. If the valve body shifts freely by hand and the coil is electrically dead, the body usually doesn't need replacing. Check the wiring harness for cracked insulation or corroded pins first — a bad harness can mimic a dead coil.

How do I tell a 12 V coil from a 24 V coil?

The rating is moulded or printed on the coil body. If it's worn off, measure resistance: at the same wattage, doubling the voltage gives you roughly four times the resistance.

Does polarity matter on a DC coil?

On a two-wire coil without a diode or LED, no. Coils with a diode, indicator, or suppression circuit are polarity sensitive — wire them as marked.

The coil measures correct resistance, but the valve doesn't work. Why?

Could be a stuck plunger, voltage collapsing under load, or a controller that isn't commanding the output. Check the voltage at the connector under load before blaming the coil.