25hp johnson manuel primer

does the engine rely on the Manuel primer at idol for fuel.

Re: 25hp johnson manuel primer

or is its sole purpose for prestart

Re: 25hp johnson manuel primer

manual prime is only to fill the carb bowl(s) prior to the motor running. After that, the fuel pump takes care of the same job. The fuel pump is driven by pressure changes from the motor, so as long as the motor is running and the fuel pump diaphragm doesn't have a hole/leak, fuel is pumping to fill the carb. Of course, fuel still has to flow through the priming bulb, since its on the connection from the tank to the motor.

-E

Re: 25hp johnson manuel primer

thank's for the info but im not talking about the primer bulb, mine has a primer bulb in the fuel line, but it also has a Manuel primer that you pull an it squirts fuel in to the carb an intake. maybe i should be calling it a mechanical primer [not electric]

Re: 25hp johnson manuel primer

outlaw241 said:

or is its sole purpose for prestart

Click to expand...

Yes, used for prestart. Here's an excerpt from the outboard starting procedure (http://forums.iboats.com/showthread.php?t=225510)...

Manual Primer

The manual primer operates as both a fuel injector and an enriching device. The fuel injector operates w/o air being drawn through the motor. The enriching device is an alternate path from the carburetor to draw fuel through the primer and add more fuel during cold-start.

1. Put motor in neutral
2. Place the throttle in the start position.
3. Cycle through one or two full pull-push operations on the primer knob. This will squirts fuel into the intake manifold.
4. Pull out primer knob one half-to full out. This will engage the cold-start enricher circuit.
5. Pull the starter rope, or press start button until the engine starts.
6. As the engine begins to run, slowly slide the primer knob in. The rate of choke disengagement will vary greatly with each individual outboard. Some require immediate disengagement, others require slow disengagement. Know your outboard.
7. Visually inspect tell-tale for solid stream indicating proper cooling.
8. As the choke is disengaged and the motor warms up, slowly back the throttle off from start to the shift position.

Re: 25hp johnson manuel primer

my problem is when at idol if i push the Manuel primer all the way in it will stall my engine, is this normal or do i have something blocking the slow speed jet?

Re: 25hp johnson manuel primer

bump

Re: 25hp johnson manuel primer

I would think that the primer should be all the way in for normal operations. I will see if I can locate a manual tonight and double check it for you.