Where is the vent on 1970's 6 Gallon Johnson Tank

[rfields109]

Shouldn't there be a vent on this standard old 6 gallon tank so the fuel pump can pull the fuel up to the motor?

 

[Chinewalker]

Re: Where is the vent on 1970's 6 Gallon Johnson Tank

If it is a standard OMC single line fuel tank, then the vent is built into the fuel fitting on the tank. Those little pins on the face of the connector get pushed in to vent the tank. They help keep the tank from venting when the hose isn't plugged in, as well as keep fuel from backing up out the vent...

 

[rfields109]

Re: Where is the vent on 1970's 6 Gallon Johnson Tank

Do they ever get clogged up on a tank that has sat unused for a long time??
How do you clean it?

Plus the aftermarket hose ends I bought do not seem to be very good and leave about 1/4" space between the fuel line fittings. I can only assume that this is a problem.

 

[F_R]

Re: Where is the vent on 1970's 6 Gallon Johnson Tank

Do they ever get clogged up on a tank that has sat unused for a long time??
How do you clean it?

Plus the aftermarket hose ends I bought do not seem to be very good and leave about 1/4" space between the fuel line fittings. I can only assume that this is a problem.

1/4" is way too much. Are you sure they are OMC hose ends and not Yamaha or some other look-alike? The pins don't stick out anywhere near that much. The vent itself is a large circular device coming up from the bottom of the outlet housing. The pins only open a passageway to it. It is a one-way vent, allowing air to come in but not fuel to blow out. And it also includes a pressure relief in case it builds up too high.

I've seen a bazillion of them slop gas out around the pins, but have never seen a problem with the vent valve itself. In fact I don't know that I've ever even disassembled one.

 

[samo_ott]

Re: Where is the vent on 1970's 6 Gallon Johnson Tank

This is interesting. Yesterday I tried a new to me old metal single line tank on my '63 Viking 25hp. It ran great for 5 min or so and then stopped. I tried to take the cap off the tank and the vacuum was so strong it was hard to open. When I did open it up and pump it up again it ran fine again (I left the cap cracked a tad). So I was assuming it was the same thing, a plugged vent. But if it never/rarely happens, then that's odd. And I was also wondering where the actual vent was as I want to check it also. Now i know.

 

[paraboater]

Re: Where is the vent on 1970's 6 Gallon Johnson Tank

I have a old 6 gal tank and it builds pressure inside (not sure it lets any out)and Im wondering if there is a easy way to check the vent to make sure it works? I have read that it is a one way and only allows air in, how can I verify that is is working?