Johnson Service Bulletin #903 - Clamping Cutout Switch Hose

Figure 1, arrow "A" illustrates the hose clamp which has recently been added to the 1962 - 40 h.p. model RD series engines to help prevent the possibility of the cutout switch hose being cut on the flash line of the cylinder block, arrow "B".

Since this hose is a vacuum line from the intake manifold, a break or cut in it may cause the following malfunctions:

1. The cutout switch may become either partially or completely inoperative, depending upon the severity of the break, because the necessary degree of vacuum no longer exists, at idle in neutral gear, to control the diaphragm in the cutout switch.
2. If the engine runs at all, it will run erratically because some air can then by-pass the carburetor and cause a lean fuel/air ratio.

Figure 2 illustrates the clamp, lockwasher and long screw required to modify the first 1962 - 40 h.p. RD(L)-24M engines. With installation of the hose clamp and lockwasher, a slightly longer screw, part #306778, is required to insure sufficient thread engagement, and therefore replaces screw 308077.

Although figure 1 does not illustrate the clamp bent in toward the powerhead, this must be done after tightening to relieve pressure of the hose against the control lever at the point indicated by arrow "C", figure 1.

All parts must be purchased from your parts distributor. Prices are as listed in the Master Parts Price List which are subject to the standard parts discount.