Spark Plug Rainhats
We’ve had trouble with the rubber insulator caps that fit over the sparkplugs on the older ¼-ton 4×4’s. The top of the cap deteriorates with age and causes the lower part to crack. We haven’t been able to get replacements, so we’ve hit upon this idea for lengthening the life of the caps.
Put a small, flat washer on the top and bottom of the cap (see Fig.). Press the edges of the crack together and tighten the top of the sparkplug down against the washers. Of course, this can only be done on the older models, since the newer ones don’t have sparkplugs with removable caps, and the sparkplug-wire terminal Cpl H. F. Eaton
Troop A, 29th Cav.
(Ed. Note — The reason you can’t get replacements is because spark- plug insulator caps have never been stocked.)
From the Army Motors Vol 4, Page 84.
BobN – While these items were apparently not available during WW2 Army supply channels, they are generally available today as replicas.