Fuel tank vent hose

[pickupman]

I was reading Zaggnutt's thread about the tank removal and I had a question about the vent hose is pictured coming off the top of the tank. For both tanks, the hose is cracked where that cap on the end goes, and thus the cap will barely stay on. I noticed this the other week when working on the fuel system.
Is the purpose of this cap to keep things from getting in the hose, but still allow it to vent? I was thinking of just cutting off the section of the hose where it's cracked and then put the cap on again, but I wasn't sure what the cap is for and I am was wondering if this cap can keep the tank from venting property?

 

[dunk]

The cap keeps crud from blocking the hose. The actual vent size of that hose is about pin sized as it necks down real small in the rollover valve. When filling, venting is through the filler neck hose in a hose design. If you don't have difficulty filling just cut the hose back a bit and put the cap back on. If you can't fill at normal speeds consider doing the vent mod, basically drilling out the rollover valve and using 1/2" or 5/8" hose to vent to the filler neck and T off with a small vent and cap to vent to atmosphere.

 

[Zaggnutt]

Hey, didn't mean to make too big of a deal of the various vents on truck! I just wanted to point out that these vents have been there for 20 years and while we're face to face with them we can take a second and blow through them and make sure they are doing their job.

dunk is on top of it.

 

[pickupman]

Hey, didn't mean to make too big of a deal of the various vents on truck! I just wanted to point out that these vents have been there for 20 years and while we're face to face with them we can take a second and blow through them and make sure they are doing their job.

dunk is on top of it.

I wasn't too worried about it, I just thought to ask about it while we were on the subject. Your write up on the tank removal was very helpful btw, thanks for doing that.

 

[opusd2]

Like any of the other vent lines, the higher the better. Take for instance filling up your truck tank in summer. If you fill the tank to the top when the weather was pretty cool out and you have a pretty warm day out the next day, the fuel will expand and want to go somewhere. Put the vent line up high enough and you don't mark your territory like my old Harley does.

 

[Zaggnutt]

I wasn't too worried about it, I just thought to ask about it while we were on the subject. Your write up on the tank removal was very helpful btw, thanks for doing that.

I'm glad it was helpful! Good luck!