Steve in fl
New Member
Hey all, new here - I need help!
I have aquired a clean 86 vmax. It had spun #2 rod bearing, then been rebuilt by a professional yamaha mechanic. It has 50 EASY miles on it, and spun #2 rod bearing again. the crank, rods, bearings had all been replaced.
I'm an automotive engine builder, so I studied the parts as I dissassembled. here's what I found :
the oil galley pipe that provides the pressurized oil to the main bearings has a restriction in the bottom of the #2 supply pipe. It's right where the 1/4" pipe is welded to the larger diameter pipe, and appears to be about 1/16" hole drilled into the main oil pipe. the other supply pipes to the other mains don't have it.
It seems NON coincidental that the main with the restricted oil flow keeps wasting the rod it feeds.
My Question is 1) is this restriction normal? if so, why?
2) can the restriction be drilled out to provide full oil flow without any other adverse effects in the engine?
Thanks in advance - Steve
I have aquired a clean 86 vmax. It had spun #2 rod bearing, then been rebuilt by a professional yamaha mechanic. It has 50 EASY miles on it, and spun #2 rod bearing again. the crank, rods, bearings had all been replaced.
I'm an automotive engine builder, so I studied the parts as I dissassembled. here's what I found :
the oil galley pipe that provides the pressurized oil to the main bearings has a restriction in the bottom of the #2 supply pipe. It's right where the 1/4" pipe is welded to the larger diameter pipe, and appears to be about 1/16" hole drilled into the main oil pipe. the other supply pipes to the other mains don't have it.
It seems NON coincidental that the main with the restricted oil flow keeps wasting the rod it feeds.
My Question is 1) is this restriction normal? if so, why?
2) can the restriction be drilled out to provide full oil flow without any other adverse effects in the engine?
Thanks in advance - Steve
