How to Wire a 4-Terminal Solenoid That Replaced a 3-Terminal Solenoid

Updated 08/13/2020 | Published 04/29/2019

Question:

On a four post solenoid as a replacement for a three post one I hooked my starter wire to the one marked with S and nothing to the I side and the battery wire to the right side and the starter wire to the left post, this on an old Ford tractor I was assured this would work. Have I missed something, it did not do anything. it had a good ground

asked by: Kenneth B

Expert Reply:

A 4-terminal starter solenoid like the Pollak # PK5230701 needs to be wired so that the 12V power in/out is connected to the two larger terminals while the two smaller terminals are connected to ground and an ignition source. A 3-terminal solenoid grounds through the hardware so if you didn't run a wire for ground to the 4-terminal solenoid then that is your issue.

If this doesn't fix your problem let me know what solenoid you are using and if we carry it I can reach out to the manufacturer for any other recommendations.

expert reply by: Jon G