Center Main Bearing Block-Valve Problem

Rebuilding 1997 Yamaha 150HP 2 stroke S150TXRV powerhead.<br />( Click here to view updated blog with new pictures )<br /><br />Inspecting the crank side of the block found that for the lower center bearing, the valve that connects back to cylinder 3 is missing the piece inside the "fingers" so that there is two-way flow instead of one-way flow through that valve.<br />(I assume this valve is for lubing the main bearing).<br /><br />How to correct this? I don't see any easy way to remove the valve from the block. Should I pry open one or more fingers, and insert the same floating piece from one of my old puddle valves, then close the fingers? Or are we talking drilling this SOB out...and then of course I must ask the obvious:<br />What about just leaving it as is...how much of an impact will this have on my compression?<br />(Please don't hollar at me rodbolt).

Re: Center Main Bearing Block-Valve Problem

exactly where is this valve located. I am having trouble picturing it. look on the yamaha parts website and give me the reference number or part number.\

Re: Center Main Bearing Block-Valve Problem

3 624-11379-00-00 VALVE,CHECK 2<br /><br />I can get you a picture if you want...<br /><br /><br />...here's a picture<br /> Click here for pic <br /><br /> Click here for closeup

Re: Center Main Bearing Block-Valve Problem

What do you think RB, is this fixable?

Re: Center Main Bearing Block-Valve Problem

yamaha part # 624-11379-00-00<br />its very easily removed. its actually a very flimsy piece and easily pliable. i used to have a small pick i modified to make it easy.<br />its on the first and second page of the yamaha online parts list under "cylinder/crankcase"

Re: Center Main Bearing Block-Valve Problem

I am with BenC they pop out easily are are cheap, check the recirc check valves while your checking valves.