Re: OMC Shift Adjustment - Stuart's Article
The 7-5/8" came from an image out of an OMC Service Manual (page 11-16) that Stuart has linked in his Cobra doc (tcable1.jpg I think). But I think it must be earlier than the '89 OMC manual (which is what I've got) because Stuart's image specifies to set the bellcrank angle by aligning the lower edge of the shift cable guide tab flush with the pivot housing gasket surface. My '89 manual (and I assume later versions ) specify to set the bellcrank angle using the special OMC alignment plate.<br /><br />Here's what the tcable1.jpeg image on Stuart's site says:<br />_________________________________________________<br />82 1. Position swivel retainer C at end of threads. Move shift cable guide D in or out until lower vertical edge of guide tab is flush with pivot housing gasket surface. <br /><br />83 2. Slide casing guide F at engine end of cable in or out to set a 7-5/8" +- 1/32" dimension G as measured from the center of the shift pin hole H to the edge of the cable crimp I.<br />_________________________________________________<br /><br />The newer (I assume) manuals state that you must use the special OMC alignment plate to set the bellcrank angle, and then set the shift cable dimension at 7-9/16 inches at the engine end.<br /><br />Interesting to note is the discrepancy on Stuart's annotated document OMC SERVICE TRAINING, <br />SHIFT SYSTEM ADJUSTMENTS for "KW-RG" (1986-1991)<br />CLUTCH DOG MODELS.<br /><br />The OMC document states:<br />C. Perform the transom bracket shift cable adjustment. Use only the 914017 alignment plate to hold the bellcrank at the 90 degree position. Always use the new 915271-M tool to hold the 7-9/16" dimension. "PW" (1990) and newer models may have a collared retainer nut on the aft end of the shift cable core wire, leave it off! <br /><br />Stuart's annotation states:<br /> Note from Stuart: OMC demands that this adjustment be made using two of their special tools (see Recommended Tools for adjusting the Cobra shift linkage (76k JPEG)). I found the previously OMC-recommended procedure in the OMC Cobra Service Manual: see 11-16 (290k JPEG) and 11-17 (288k JPEG). This "obsolete procedure" requires only a straightedge, ruler, and some wrenches, although it would go faster if you have a helper. When I last performed this adjustment, I had to climb into and out of the boat five or six times; I've decided that's O.K. since I'm only adjusting one boat. If I worked at a marina, I might feel otherwise. <br /><br />The intent here is to adjust the distance between the hole in the cable end and the cable jacket. The adjustment is simple if you have the sterndrive off. Examine picture #83 in 11-16 (290k JPEG); if your dimension "D" is 7 5/8 inches (+/- 1/32 inch!) when in Neutral, you need adjust nothing. Of course, if you have just replaced your transom shift cable, you already have the sterndrive off, and you can adjust this yourself easily. <br /><br />Note that the first OMC intructions, using the alignment plate state 7-9/16". The annotated, alternate intructions (also from an OMC manual), aligning the shift cable guide tab, states 7-5/8". I wonder if the difference in length is related to a change in OMC setup specs or to the different methods of setting the bellcrank angle (lining up the shift cable guide tab with the pivot housing gasket surface vs. using the alignment plate to set the bellcrank at 90 degrees)?<br /><br />Ah, the intracacies and mysteries of the Cobra shift adjustment!!
