fuel problem 70hp johnson outboard

loyal dragon

Hi guys im new to this forum.
I have a problem with my johnson outboard 70hp.
I was comming back into the bay and the engine felt like it was running out of fuel, the engine stopped and i primed the hand pump(globe) and the engine will run again.
I have checked my fuel and the lines and they are ok.
can anyone help and also there seems to be a fuel pump like device on the side of the block, does that run of a pusle?
regards Basil

starcrafttom · Posted: Fri Jul 24, 2009 2:25 am Post subject:

I would say that you have a air leak in your fuel line some where. You will never see it but it the bulb is going flat and you can pump it up and the motor runs for while and it happens again I would replaces the bulb if not the whole line.

loyal dragon · Posted: Fri Jul 24, 2009 2:33 am Post subject:

Jack in Alaska · Posted: Fri Jul 24, 2009 4:01 am Post subject:

I would also check the fuel quick connections. Those Johnson quick connects have an "O" ring in the fuel hole and they deteriorate causing it to suck in air which will cause your motor to do exactly as your motor is doing. Replace them along with the bulb and fuel line.
I always carry a complete new fuel line set-up that will connect directly to the tank and then the motor thereby eliminating all of the other fuel lines/connections/filters etc.

Good luck.

Sea Wolf · Posted: Fri Jul 24, 2009 6:28 am Post subject:

Once you've eliminated

1) the supply line and the gaskets check out:

2) the pick-up tube in the tank,

3) the check valve in the primer bulb,

4) an in-line external filter, if present, (such as the Racor type used on later 4-stroke engines), sometimes added to older set-ups

5) a small cylinderical in-line filter under the motor shroud, if present,

6) the fuel pump itself, on the side of the powerhead, which has a filter screen in it and is operated by crankcase pressure- (the screen must be clean, of course, and the Neoprene diaphram must be intact, and the whole pump sealed up tightly enough that air doesn't enter,

7) the carburetor needle valve(s) and jets,

Pumping the primer bulb can force fuel through a partially clogged part in the system or past an air leak. Either one can stop the fuel flow.

Joe. Teeth

C-Otter · Posted: Fri Jul 24, 2009 12:52 pm Post subject:

Is the tank vent open? Rolling Eyes

C-Otter

Jimbo · Posted: Fri Jul 24, 2009 7:33 pm Post subject:

Not sure what kind of tanks you have but as was just stated, check to make sure your vent is open. For some reason on one of my tanks I have had to crack the actual filler cap open to get enough air into the tank.
Jimbo

loyal dragon · Posted: Wed Jul 29, 2009 7:56 pm Post subject:

cheers guys, all tips are great especially sea woff Beer

yes i found the o ring on the quick connector fauly, I have replaced the whole line and it is now holding presure, I ran the motor with the muffs on for 15 mins seems fine but will need to check it on the water, will take tools and parts with ofcourse Beer

loyal dragon · Posted: Wed Aug 26, 2009 3:38 am Post subject:

well you wouldnt know it, I finaly found my problem, the pick up tube was the exact lenth of the tank, it was sucking in the bottom of the tank and starving itself of fuel