Catalina 30 TRBS #2889 "Northern Light"

5411 diesel glow solenoid

The rest of the modifications.

I modified the glow plug wiring so that my glow plug only needs to be on for 5-6 seconds before cranking. Essentially what I did is to mount a small starter solenoid (the type that is used in garden tractors and available at auto parts stores) right at the engine so that the heavy glow plug current was now switched by the solenoid rather than through 20 feet of small gauge wire to the engine control panel. So, the switch at the control panel activates the solenoid, and the solenoid supplies current to the glow plugs.

The solenoid gets a good source of current because it is connected directly to the 12V stud on the starter.

The solenoid has a black cap that covers the two studs at the top. These studs get the thick (#10) green wires with ring lugs at the ends. The green wire on the right goes from the solenoid down to the large 12V starter lug. The green wire on the left goes from the other solenoid stud to the glow plug (when then has a jumper to the second plug.) The tan coiled wire is the wire that originally went from the glow switch directly to the glow it goes only to the small coil screw on the solenoid. The solenoid metal mounting bracket must be grounded to the engine because that's the other coil connection.

The starter circuits doesn't have a fuses or breaker. It's the same case as is found in automotive wiring. The protection, therefore, is to keep the cabling short and mechanically protected. Since the solenoid circuit is an extension of the starter cable it's therefore good to keep it similarly short and protected.

Note: an issue with certain makes of these solenoids pertains to the internal coil wiring. One coil wire connects to the small threaded stud. The other coil wire connects to the metal mounting plate. It seems that some manufacturers solder that wire to the metal plate while other manufacturers simply crimp that wire under a folded section of the plate. That crimp failed (corroded) on my solenoid a couple of years ago and I had to replace the solenoid.