Fuel tank problem?

I just bought my first boat and motor. The motor is a 1989 Johnson 30 horse. The fuel tank is a metal 6 gal. OMC tank. There is no vent on the cap of this tank and I am wondering if I need a vented cap. I have had some problems starting the motor at times and keeping it running at other times. I am a complete novice and think it might be operator error also.

I thank everyone for the replies and advice. I was leaving the fuel line hooked to the tank and the engine when I put the boat in my garage. The next day I found a puddle of gas under the motor. Gas was leaking out of the exhaust on the engine. I thought, if it is vented somewhere in the fuel line connections, why is the fuel being forced out the exhaust.

Which is why I say I liked cracking the tank cap or getting a vented cap better. Where the vent is......is where they want to "bleed." If the vent is above the liquid level like a vented cap or by just cracking the cap, no leaky leaky.

More than once I had the expanding gasses "venting" there and either filling up the back of the boat or coating the lake with a nice oily sheen and dripping all over the motor and transom, or both.

Perhaps I had a worn part or something and that's why it leaked there. But it did, so I wound up getting a special cap with a vent.

Haven't you taken a gas can out of a rowboat or whatever and left it capped tight and had a pool of gasoline in your garage?

hi, the tank is vented by the hosse connection. if you look at the fitting fron the motor to the tank you will notice 2 prongs coming fron the tank 1 is for gas and the other is the vent. no screw on cover. omc tanks have been this way ever since the 60s. i right now am running a omc tank on my merc. got sick of opening the valve on the cover and the tank not venting right. omc tank works good. tight lilnes ducore

If I remember right my old evinrude the gas tank vented when the gas hose was snapped on the tank. I do know there was no vent on the gas cap. Mine also had the twin hose so Irhink that was how it vented

I believe those are meant to be cracked but not open. We had a 1989 vintage gas can that my dad bought that year with a 6hp OMC motor. Same deal, no vent. Just cracked the tank cap.

My advice would be to leave it that way or next time you park that thing in the sun the gas tank will swell like a balloon. Something bad's going to happen because those gasses are going to expand no matter what. Either its going to force back into your engine, or find some other place to relieve its own pressure. This can be a mess.

Vented caps don't do this. Sure seems like you could pick up a vented cap. If it becomes a problem, I just picked up a 3 gal tank for like $24 at FF, plastic. I know they had 6 gal ones.

And also remember if you open the cap....no smoking.....

Smoker....

Back in the 60's, we had the same metal tank. We would just pop the gas cap loose a little to get started and keep running. Just remember to position the tank in the boat with the gas cap end of tank towards the front of the boat so as to not leek gas out of tank on take-off.

Theres always been a vent on all remote tanks that i have had. Needed for proper operation. Spinman