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2004 Johnson 50HP VRO to Mixed fuel pump conversion

BlackPinapple

BlackPinapple

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I recently swapped out my defective VRO pump for a straight mixed fuel pump on my engine. I mounted the new pump using the crankcase pulse hole and through a cap over the pulse limiter and the pulse line in port on the new pump. After running the engine for about 30 seconds I heard two loud pops and noticed the two caps i put over the ports have blown right off. My question is do i need to remove and plug the pulse limiter and the pulse port on the new fuel pump or can i just throw a hose on connecting the two even though the fuel pump is running off the pulse hole in the crankcase? Thanks in advance!
 
Part # of your new pump ?------Did you mount the new pump using 2 screws and a gasket on the side of the top cylinder ?-----The pulse limiter is a " flow fuse " for the VRO.-----That pulse limiter is not needed on a conventional pump !-----Normally you would remove the pulse limiter and install a pipe plug there.-----More details needed here.
 
racerone said:
Part # of your new pump ?------Did you mount the new pump using 2 screws and a gasket on the side of the top cylinder ?-----The pulse limiter is a " flow fuse " for the VRO.-----That pulse limiter is not needed on a conventional pump !-----Normally you would remove the pulse limiter and install a pipe plug there.-----More details needed here.
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I used this pump ordered off Amazon 438559 Karbay Fuel Pump 385784 433390 438559 For Johnson Evinrude 25 35 50 65 70 75 85 88 90 100 105 115 125 135 140 HP

And yes I attached it directly to the block with the gasket but as you can see there's a secondary pulse line in on the pump. Would it be harmful to just reattach a line between that pulse inlet and the limiter pulse outlet?
 
I would not use the 438559 pump on a 50 HP !!-----Pumps operate with PRESSURE from the crankcase.-----The long hose is NOT NEEDED with a proper installation over the pulse port on the side of the #1 cylinder.-----The pulse limiter is NOT needed with the conventional pumps !!-----Online listing are not always " spot on " with applications either !!
 
racerone said:
I would not use the 438559 pump on a 50 HP !!-----Pumps operate with PRESSURE from the crankcase.-----The long hose is NOT NEEDED with a proper installation over the pulse port on the side of the #1 cylinder.-----The pulse limiter is NOT needed with the conventional pumps !!-----Online listing are not always " spot on " with applications either !!
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Oh geeze, so which pump should I be using? Why wouldn't I use the pump I used?

Thanks!

Ah just saw your other post about the pump for this conversion.
 
Note-----I own more than 1 of these 2 cylinder motors ( bought 4 last year alone ) for rebuild / parts.-----As clearly stated in post #3 the 438556 is the correct one that I would use !!!
 
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