Moeller Tempo Manual Vent Gas Cap, Black (621501-10)

I wish I would have found out that I needed this cap years ago! I have an old 2 cycle 9.5 hp Johnson outboard on my Jon boat. I have a 3 gal plastic Attwood gas tank. The motor has been flooding out and leaving us stranded on the lake 4 times in a row! I kept taking it in for repairs and spent @ $400! Having carburetor work done, impeller replaced, spark plugs changed, and fuel line and bulb replaced. All that money and hassle and it turned out to be something simple. The gas can was the newer type where it was not vented for EPA requirements. The plastic gas tank would swell in the sun and heat, and this would force gas back up the fuel line and flood out the carburetor. It would also cause gas to come out the exhaust and spill out in the lake! The boat motor would run great in the morning, but in the afternoon heat it would flood and never start back up! This would leave us stranded over a mile from the boat ramp! The vented gas cap fit perfectly on the 3 gallon Attwood tank. And now the motor never floods or leaves us stranded after putting this vented gas cap on. I feel ridiculous for not finding out about this easy fix sooner! The newer non vented plastic gas tanks are a stupid idea in my opinion! The may prevent gas fumes from escaping, but they cause flooded outboard motors and tons of gas and 2 cycle oil being dumped into lakes and waterways causing major pollilution and damage to the natural ecosystem!

Looked smaller than the original but fit perfectly and works great

I have been frustrated with my new "eco-safe" gas tanks. With the cap provided, it seems gas is forced into the motor due to the pressure in the can. This Moeller Tempo Manual Vent Gas Cap fits the tank perfectly and instantly solved my problem. I am so happy, I have ordered a second one. Good product.

The current EPA mandated vented fuel tank caps do not release pressure until it gets very high. This results in the tank ballooning, extra fuel being forced into your outboard, and fuel leaking from fittings and connections that are not perfectly sealed. This cap solves that problem by simply venting the tank vapor to the atmosphere whenever the vent is open. My pontoon boats sits in the water all summer and I leave the vent open all the time, no problems, no leaks, and the cap prevents rain or water from getting in. It just works.

I was a little hesitant on buying a gas cap online but it fit perfectly and appears to have a rubber seal where the cap snugs up to the throat of my tank which is an older plastic 6 gallon Dura-Tank. Believe it or not it even fits my lawnmower tractor's gas tank! The cap was a little pricey but it looks like it's worth the money. Much cheaper than buying a whole new gas tank. Thanks for a quality product.

My gas tank was causing problems because of the lack of venting. On a hot day, the gas would expand and push gas into the engine and flood the motor. Also, the gas tank would become extremely distorted to the point where the pickup tube was no longer at the bottom of the tank so I basically was running out of gas even though I still had at least 1/4 tank (and the only reason I was that low on gas is because gas was being pushed into the engine and then out into the water). Instead of venting some gasses into the environment, I spilled a lot of gas into the lake. Great job environmental law! At any rate, this gas cap is the solution. When the boat is being used, I turn the dial to vent the tank. When in storage, I keep ti closed. This solved the problem. Note that these caps seem to fit any standard tank. I bought an extra one of these gas caps just in case they aren't available in the future. Who knows if some environmentalists outlaws them.

If you have purchased the 6 gallon attwood marine gas tank get this cap!!! At 70 degrees F that tank will at least double in size producing enough pressure to force gas all the way thru the primer bulb and lines and then floods out the carbs and pours out on the ground. I was blown away lol. But This 3D printed cap solved all that

Perfect fit on an older tank with a Kelch style cap. Simple and functional. Mine is an older “Honda” branded tank, which was probably made by Moeller anyway. Fits great and doesn’t leak, even tipped upside down.