vented gas tank

[Brento311]

Hi, earlier I posted about having a piece of junk elgin 7.5 HP because it kept cutting out on me. Well, a friend of mine told me it might be because I didn't have a vented gas tank. I got home and looked at the 40 year old tank, and it doesn't have a vent at all! What do I do, just take the cap to the tank off? Any suggestions would be very helpful!

 

[captsara]

Re: vented gas tank

what is your tank made of?

 

[Fouled Plug]

Re: vented gas tank

Brent, I'm 99.9% sure you have a metal tank. It may have a vent built into the cap that is malfunctioning, or no vent at all. If your Elgin has a fuel pump and draws from it, you will need some sort of air intake to prevent a vacuum. Either a vented cap, or a dedicated vent in the tank. You can test your friend's theory by running with the cap cracked, or waiting till the motor starts to stall and opening the cap.

 

[Rock Man]

Re: vented gas tank

Ya I would try to cracking the cap on the tank for a little air flow, but is this possible for the motor to shut down for not having appropiate venting???

 

[petryshyn]

Re: vented gas tank

Ditto on Fouled plug<br /><br /><br />Yes rock man<br />if a tank that requires venting has no venting, it'll slow the engine down alright. Nothing allowed in means nothing allowed out. It'll slow you down(runs lean) according to how bad a restriction. Total restriction = engine dies.<br /><br />Brent311<br />How many hoses going to tank? One round hose? Two hoses side by side?<br /><br />>one round hose = needs venting (has fuel pump)try "Fouled plug's" test<br /><br />>two hoses = needs to be sealed, cap must be tight (has no fuel pump, relies on crankcase pressure)<br /><br />hope this helps somewhat...

 

[Brento311]

Re: vented gas tank

hey, thanks for the advice. The tank has a single round hose going to the motor. It is an old metal tank, and I believe it is a 2 gallon. There is no vent that I can see on it, and i don't think the cap is vented.

 

[Fouled Plug]

Re: vented gas tank

You may be able to find a vented cap at your local boating supply place that will fit the tank. It may be less hassle to just get a new plastic tank with a vent, though. Try running the motor again with the cap cracked, and see if the old Elgin likes that better before you go shopping.

 

[Brento311]

Re: vented gas tank

This afternoon, I looked even closer at the old Elgin fuel tank and noticed that there is an air vent next to where the hose goes in...it's just a little screw next to the hose. What do I do to vent air in, just unscrew it all the way? Thanks

 

[PurpleDragon]

Re: vented gas tank

That should do it!<br /><br />Rex S.

 

[Fouled Plug]

Re: vented gas tank

You don't even have to back it out all the way, Brent. Just a couple turns from seated shoud do it. Let us know how your next trip turns out!