There are two special fittings in the M38 Underwater Ventilation System.
1. The first special fitting is found on all M38s. It is located in the vacuum supply of the distributor ventilation system at the Wiper Tee fitting.
The special fitting is Connector, 7348568, WO-802665. It is a brass inverted flare fitting; 3/16" tube, 1/8" pipe Male Connector. What makes it special is the center hole is a .040" orifice.
End view and side view. The drill and needle show hole size on each end.
This fitting can be easily fabricated from a
standard Male Connector (Weatherhead #202x3) by filling the center hole
and drilling it out with a .040" drill bit.
2. The next special fitting is only used after Engine #74419. This is the late style venting system. On these vehicles the bellhousing is sealed and a vent line connects the bellhousing to the center section of the fuel pump. This special fitting is a ball check valve located at the elbow near the fuel pump.
This special fitting is Connector, 7375063, WO-8000347. It is an SAE 45° Flare fitting Male Ball Check Connector 3/16" tube, 1/8" pipe.
This special fitting is still available from Fairview fittings. It is a brass ball check, part number 43-3A. This special fitting could be replaced by a standard SAE 45° Flare fitting Male Connector 3/16" tube, 1/8" pipe (Weatherhead #48x3). The lack of a check valve will not make a significant difference in operation.