Friends, thanks for all your prompt advice of late. I have read all the info that I can find on this forum concerning the "oil flow diverter plug" (not sure what it is called). It is the movable plug just above the oil filter line outlet at the bottom of the block which allows the oiling system on a 261 to be either a full-flow or partial flow. One stovebolter on a previous post was dead sure that the plug "driven in" was the correct position for full flow, another poster was equally sure that the "out or flush" position was for full flow. As you know, I have recently disassembled two 261s, one with the plug driven in, the other in the out or flush position, yet, both allowed for bypass oil flow. Upon closer inspection of the one with the plug driven in, it appears that a previous owner had drilled through the plug via the oil pump input hole, thus converting the full flow back to a partial flow (can't imagine why he did that). To verify this, I drove the other plug in all the way and am now "dead sure" that it is in the full flow position. I am posting this, subject to any corrections, in case others were confused by previous posts. Thanks again for your invaluable help...Ron B


Ron B