Bill, I'll send you these Service Bulletin(s) but here's what it says-
"M-113A
Prior to March, 1951 it was necessary to disassemble the mechanism to service the check valve. Figure 1 shows the old design, which requires removal of the diaphragm to service the check valve. (See Service Bulletin M-81A).
Since March, 1951, the check valve has been located as shown in Figure 2. Of course, it is first necessary to remove the mechanism from the housing. (See Service Bulletin M-82).
The orifice plug shown in Figure 2 is made of stainless steel and normally should not require replacement. However, if exceptionally bad operating conditions make replacement necessary, the orifice plug can be extracted as indicated in Figure 2. Then, invert the diaphragm cover and properly align the new orifice plug with the receiving hole in the casting, so as to avoid damaging the orifice plug when driving it into place.
CAUTION: The orifice plug should be driven in as far as possible against its shoulder, employing a BRASS rod so as not to damage the seat on the plug. NOTE: In case a new diaphragm cover is ordered, the orifice plug will already be installed in the casting."
Ron Scobie
c/o Ron Scobie Enterprises
7676 - 120th Street North
Hugo, MN 55038-9426
Phone - (651) 653-6503
Email - rscobie@gaspump.com
Website -
http://www.gaspump.com
