Fuel system vent

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JMichael

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I'm having a problem with my fuel system. When you first connect the fuel line and start to prime it. As the fuel flows from tank to carb, the air has to vent. Is the carb bowl vent the only place that happens, or is there another vent somewhere?
 
New fuel tanks...no vent....how stupid is that! Thanks EPA. You should add a fuel demand valve in the fuel line. It is almost necessary to keep from flooding your engine all of the time.

This only applies to the new EPA tanks. I've heard of some people finding old fuel tank vented caps and putting them on the new EPA monstrosities, too.

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https://www.walmart.com/ip/Attwood-Corporation-Fuel-Demand-Valve/23619765?wmlspartner=wlpa&selectedSellerId=0&adid=22222222227017153063&wl0=&wl1=g&wl2=c&wl3=40969022792&wl4=pla-78911849912&wl5=9027643&wl6=&wl7=&wl8=&wl9=pla&wl10=8175035&wl11=online&wl12=23619765&wl13=&veh=sem
 
Pappy, of course, you are correct.

The lack of an ...EXIT... vent causes the new tanks to blow up like large semi-round balls. The sides are now made of stronger and thicker plastic to handle the pressures.

What a plan!!! Wait until one of the new inflated tanks spawns a pin hole leak and gasoline sprays out all over the stern hold. I hope no modern day fisherman smokes or uses cigars or a pipe!

I think my new tank in the 1652 G3 takes up more room when it is inflated, which is often. Gee, where did I put that old vented cap from the former plastic tank?

richg99
 
richg99 said:
Pappy, of course, you are correct.

The lack of an ...EXIT... vent causes the new tanks to blow up like large semi-round balls. The sides are now made of stronger and thicker plastic to handle the pressures.

What a plan!!! Wait until one of the new inflated tanks spawns a pin hole leak and gasoline sprays out all over the stern hold. I hope no modern day fisherman smokes or uses cigars or a pipe!

I think my new tank in the 1652 G3 takes up more room when it is inflated, which is often. Gee, where did I put that old vented cap from the former plastic tank?

richg99
Im a modern day fisherman and I smoke a pipe and cigars both. But I have older tanks with vented caps. Cigars and fishing & cigars and golf. Retirement is good.
 
Pappy said:
New tanks do have vents but they only vent in.....not out. With no vent eventually any engine would starve for fuel.

I found that out the hard way yesterday. Out on the lake I noticed my tank was collapsing in on itself. Happened because I had shut the vent off the previous day and forgot to reopen it. When I opened the vent you could hear it sucking in air.
 
richg99 said:
Pappy, of course, you are correct.

The lack of an ...EXIT... vent causes the new tanks to blow up like large semi-round balls. The sides are now made of stronger and thicker plastic to handle the pressures.

What a plan!!! Wait until one of the new inflated tanks spawns a pin hole leak and gasoline sprays out all over the stern hold. I hope no modern day fisherman smokes or uses cigars or a pipe!

I think my new tank in the 1652 G3 takes up more room when it is inflated, which is often. Gee, where did I put that old vented cap from the former plastic tank?

richg99

I'm not 100% sure but for some reason thought the new tanks are designed to vent out after 5 psi. That apparently is enough to cause the flooding problems you mention and for our tanks to look like miniature versions of the Hindenburg.
 
re 5 psi. you may be totally correct.

Your analogy of the Hindenburg made we think that....

The Hindenburg was only full of Hydrogen. I'd guess that Gasoline fumes might be even more explosive. One way or the other, I don't want to find out.

richg99
 
I have a few of the newer plastic tanks....and they stay on the shelf for the most part. Think I used one a couple years ago and remembered why I do not like them (think plastic football).
I prefer the older steel tanks. They work, do not distort, and have proper vents.
 
On my plastic tanks I take a soldering iron to the threads on the cap. In one spot towards the beginning of the threads in the cap I use the iron to distort it enough to drag on the tank, to hold position. I crack the cap just enough for a vent and the drag of the threads will hold the cap where I put it.
 

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