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Fuel pumpVRO lengthy thread

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pd_ho

New member
"I have had my 92 70Hp Evinrud

"I have had my 92 70Hp Evinrude completely rebuilt, we rebored cylinders (30thou) new pistons etc.. gaskets all around, pulled and cleaned carbs ( blew out every orifice) with no adjustments upon rebuild, removed vro and installed fuel pump (failed vro burned up my motor) we are running pre-mix now, Basically a new motor. I went through the 1st 10 hours of break in period with no issues( idle to 3 thou with lots of variation of speed) and last weekend I pushed the RPM's up . When I did that the motor would quickly go to 5000-5500 no problem and then bog down and speed up. I backed it down to 2-3 thou and problem gone, back up pass 3500 problem is back. If someone continued to pump fuel bulb we could maintain 4000-4500 without pulsing but not higher. We put the old vro unit back on and plugged the oil inlet and problem was the same, check for air leaks, we pulled the carbs and found nothing unusual, and checked the stator for continuity-- the only thing we can think of is if the "computer" on the VRO sensor with the VRO pump not plugged in could cause the motor to do this. I can tell its starving for fuel but I don't think its the carbs, fuel pump-- we did nothing to the high speed jets thou.

Thanks
Pete"
 
"Make sure all of the lines go

"Make sure all of the lines going to the fuel pump, especially the one from the pulse fitting to the pump, are secure and tight with no air leaks. Did you use new lines and use a new fitting on the pulse port? Nothing in the VRO wiring can shut the engine down when it is disconnected, outside of a wire shorting out. What number pump replacement did you use? If you can pump the primer bulb and she picks up, you have a pump supply problem somewhere down the line.."
 
We did replace lines but not t

We did replace lines but not the pulse port fitting (we did pull it and blow thru it to make sure its clear). And we ruled out the pump because we put the old one (vro) back on and the problem was the same. The only reason why we pulled the old was due to the oil injector going out. I don't recall the pump number but the tech guy sold it to me knowing what it was for. Should I replace the pulse fitting? I will also triple check fuel lines for air leaks again.
 
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