Converting from the compression to a pump!!

[rTagster]

Is there anything wrong with hooking up an in line pump to one of those old compression style Johnson motors. I've seen alot of posts about converting them over to a pump that seems like a lot of work. Which involves a vacuum style Mukumi pump.

I would rather get an Inline 12 Volt Low Pressure pump and just hook it up. Seems alot easier. And still cheap.

Anything thoughts or concerns?

 

[rTagster]

Re: Converting from the compression to a pump!!

is there any reason this would not work?

 

[JB]

Re: Converting from the compression to a pump!!

Your language is confusing, Ricky.

What is a "compression style" Johnson??

What sort of pump are you talking about? A FUEL pump??

If you are talking about putting an electric FUEL pump on an old JohnnyRude that used a pressurized tank so that you can use a modern, vented fuel tank, that would probably work after you have converted the fuel tank, supply lines and connectors and added a battery to the system.

You realize, of course, that you probably won't be able to charge your battery from the old style JohnnyRude, depending on year and model.

It seems to me that updating to a pulsed fuel pump would be a lot simpler and simpler to use.

 

[rTagster]

Re: Converting from the compression to a pump!!

Sorry if my language is confusing to you. I did mean the pressurized fuel tank when i said compression. And yes i was talking about the fuel pump.

The inline low pressure fuel pumps run off of 12v batteries which are rechargeable. so i dont need to worry about the motor recharging it. Its alot easier to go off a system like this rather than using a pulsed fuel pump.

 

[tx1961whaler]

Re: Converting from the compression to a pump!!

Except that you have no way to automatically shut off the pump if the motor stalls......which makes it a fire hazard. The conversion to the pulsed pump is very easy and a heck of a lot safer.

 

[tashasdaddy]

Re: Converting from the compression to a pump!!

i believe you are talking about the 2 line pressure tank motors. if so, that Mukumi has to be installed perfectly.
electric pumps are extreme fire hazards and to be avoid at all cost.

 

[Silvertip]

Re: Converting from the compression to a pump!!

Amen on the electric fuel pump. Unless they are configured so they shut off if the engine dies they can make your engine a bomb. Modern EFI/DFI engines use the ECU to kill the pump should the engine lose oil pressure (4-strokes) or should the engine die. This prevents the pump from filling the engine with fuel and going KABOOM should you try to restart it. Very bad idea and totally unnecessary.

 

[rTagster]

Re: Converting from the compression to a pump!!

So you all convinced me that i should use the mikuni pump. i got it already. and am planning on starting that conversion today.

however before i start that i was wondering if anyone knew why i would have residue coming out of the air line that sends the air to the gas tank?
This morning i sprayed some carb cleaner into the air intake to just see how the engine was doing, i've had it sitting for a few days, and the carb cleaner i just sprayed in was spraying out this air line. is that normal? do i have a broken seal somewhere?

thanks

 

[rTagster]

Re: Converting from the compression to a pump!!

also looking at the instructions on the website:

http://www.outboard-boat-motor-repair.com/Johnson/Pressureized Fuel Tanks.htm

it says i need a vacuum line cap? what is that and where can i get one?

 

[tashasdaddy]

Re: Converting from the compression to a pump!!

no idea, that is why we say stay with the old tank.

 

[rTagster]

Re: Converting from the compression to a pump!!

my tank wasnt holding pressure, so i figure i might as well convert it for 30 bucks rather than pay 20 to fix up the old tank.

 

[Chinewalker]

Re: Converting from the compression to a pump!!

You're getting residue out the air line because it draws air pressure from the crankcase. If you get stuff (unburned fuel, carb cleaner, etc.) in the crankcase, it'll come out the air line. Nothing unusual about that.

 

[rTagster]

Re: Converting from the compression to a pump!!

ok perfect. what about the vacuum line cap?

 

[rTagster]

Re: Converting from the compression to a pump!!

anybody know what that vacuum line cap does?

 

[ondarvr]

Re: Converting from the compression to a pump!!

anybody know what that vacuum line cap does?

It says vacuum line plug, it plugs the vacuum line you're not using, an auto parts store should have them.

 

[JimS123]

Re: Converting from the compression to a pump!!

my tank wasnt holding pressure, so i figure i might as well convert it for 30 bucks rather than pay 20 to fix up the old tank.

You still have to convert the tank to a single hose. That'll cost as much or more than the gasket and o-rings to seal it up. If you opt to use a newer tank, then you still have to replace the connector on the motor.

 

[rTagster]

Re: Converting from the compression to a pump!!

yes i would have to get the new connector unless i hooked the line right up to the pump till i find a cheap connector.

where does the line that sends the vacuum pulse go than? it goes from the pump to where? it doesnt seem very clear to me in the directions on that website.

 

[ondarvr]

Re: Converting from the compression to a pump!!

The directions say there are two holes, plug one with the vacuum line plug then put the cover back on. The pulse line connects to the intake manifold, its shown in two pics and then goes to the pump..

Although most of the information on converting it is there, it is a little tough to follow in some places.

 

[rTagster]

Re: Converting from the compression to a pump!!

sorry i am a complete newb with these boat motors. where does it hook on exactly? i've been staring at those pictures forever and just cant seem to make sense of whats going on there.

thanks for taking the time to help me figure it out, but where does the vacuum line hook onto the intake manifold?

oh wait now i see it i think. is that just the old air line that sends air or pressure to the tank?

 

[rTagster]

Re: Converting from the compression to a pump!!

so does no one really not know where that vacuum line goes?