A lot of our members may be aware of this information but some will probably find it new to them. Every scrap of info is a plus to know when you have a 20+ year coach.

While investigating my alternator problems, I noticed on the wiring schematics that all of the solenoids had a number beside them which I recognized as being a Cole Hersee part number. There are three solenoids using two part numbers both of which are readily still available and have been used since at least the 1980's. Cole Hersee is very good quality - nothing less should be substituted.

The info is as follows:

Start solenoid- Cole Hersee #24037- intermittent duty unit designed for starter applications- located near starter- location may vary due to engine type.

Master Relay- Cole Hersee #24106- 85 amp, continuous duty unit, located in forward compartment driver side.

Rear Accessory Relay- Cole Hersee #24106- 85 amp continuous duty unit, located on engine compartment firewall, location may vary due to engine type or rad location.

It should be noted that the Master relay is controlled by the ignition key and the Rear accessory relay is controlled, in turn , by the master relay via a circuit breaker feed. No master relay operation then no rear accessory relay operation. If the master unit works and the rear accessory unit fails, all the forward power will function but the engine will not start due to the Rear Accessory Relay controlling the engine fuel solenoid via a circuit breaker feed.

Although the master relay appears to be the one that fails most often, the rear unit is equally important. Both of these units are operated every minute the key is on- they take a beating.

I intend to change all of mine out for new as well as parallel a second unit for the Master and rear accessory units. I would recommend, at the minimum, all old units be replaced immediately and keep the removals as spares. Reliability is the name of the game when you are out in the boonies or ready to leave a major event and you have a no start.

The #24037 is $33 on Amazon and the #24106 is $24- very reasonable- or shop around at your favorite supplier.

An update on my solenoid information. Went to order a #24037 this morning and found that there is a replacement number - #24071. There may still be some #24037 inventory left around with suppliers. Similar pricing prevails.

excellent. thank you.