Hose routing for new fuel pump - 1999 Johnson 50 hp

kenmiller476

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Aug 23, 2008
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I have now replaced the powerhead and removed the VRO system. I have searched and searched the forum and YouTube for directions on how to route the hoses from the new fuel pump without success. I am guessing that the hose from the pulse nipple of the new fuel pump should be attached to the pulse limiter behind the starter, but just having spent $1,000 for the replacement powerhead I am a bit gunshy abut assuming anything. Also, I am not clear how to plumb the manifold in the new setup. Any guidance would be gratefully accepted and appreciated.
 

racerone

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The pulse limiter is a flow fuse for the VRO.------It is to be removed and a pipe plug is installed.----The proper fuel pump for your motor mounts right over the pulse port in the side of the top cylinder !------You remove the plug there and install the pump with 2 screws and a gasket.------Fuel goes in the pump filter cover.-----Fuel comes out of the other nipple.
 
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How did you have it set up? were you trying to use a v6 pump to work with the pulse line? but do what racer said.. to the right of the starter bracket up top a few inches below the flywheel you will see 3 holes in a row... one capped with a screw. i have made up a bunch of fuel manifolds with the correct size t fittings, fuel hose and primer hose if you want one for $15 plis $3 for shipping
 

kenmiller476

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Aug 23, 2008
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The fuel pump that was supplied to me by the vendor, but not mounted to the powerhead has a sticker that identifies it as pert # 438557. Is this not the correct fuel pump? You can see why I am a bit confused.
 

kenmiller476

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Aug 23, 2008
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I probably should have added that this fuel pump has three nipples and I would like to use it if possible because I already own it. Thanks.
 

racerone

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Some vendors just do not know the proper pump or the way to mount the pump on the 2 cylinder model !!!-----Yes you can use the 438557 but that is actually for the 3 cylinder models.----Yes it will work on your motor.-----A good dealer would have sold you the proper pump !!
 

racerone

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---Follow this procedure.------Blow into the nipple on the filter cover.-----One of the other nipples will have air coming out.----So now you fuel in and fuel out.----That leaves the other nipple for the PRESSURE pulse.------Remove the pulse limiter and install a nipple ( 1/8-NPT ) to fit the pulse hose.
 
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Racer can't you use the (blue) pulse nipple on the block and just plumb it into his 3 cyl fuel pump? I did think the 3cyl-v6 fuel pumps don't work properly at idle set up that way?
 

racerone

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ct1762----Do you know the purpose of the pulse limiter ( blue nipple ) ----Yes or not sure ?
 

guy48065

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Aug 31, 2008
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ct1762----Do you know the purpose of the pulse limiter ( blue nipple ) ----Yes or not sure ?

You may educate me if you like.
Before I put my pontoon in the lake for the season (early May) I decided to bypass the VRO & use pre-mix. I did as I've read elsewhere and capped the oil line into the OB, unplugged the warning harness, flushed the hose & primer bulb with premix, plugged it in and away I went.
Since then I've been wondering if I should replace the VRO pump with the standard fuel pump. The OB does have the proper mounting bosses so it looks simple enough. Just seems possible that by plugging the oil side of the VRO pump the fuel side might struggle since they share a common linkage between the diaphragms. I've never read anything to that effect, though...
 
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