Fuel system sealed or vented?

[geusterman]

I just made an aluminum cap with O ring seal for my flatbed tank filler and it dawned on me that maybe the OE cap was vented. Am I creating a vacuum that will pull down my lift pump or such? George

 

[nickleinonen]

on the tank, i believe the service manual states that one of the aux. nipples on the tank is a vacuum relief valve so you should be safe. .

 

[geusterman]

Thanks Nick. Unfortunately that is the "nipple" I demo'd for my second vent hose for faster fueling. Hmmm. I wonder if there is another check valve in the system? Anybody? George

 

[jacqnbill]

I have my tank on the ground doing the vent mod and there are two nipples, one on front and one on the rear top of the tank. I would guess both are vents.

 

[geusterman]

Jacnbill... but ARE they? Can you look close for me? Mucho gracias. George

 

[jacqnbill]

Jacnbill... but ARE they? Can you look close for me? Mucho gracias. George

I have the tank installed already. Sorry. I did look at both of the vents or whatever they are. They are both identical. I stuck a 3hree inch nain into one and it went all the way into the tab. There is a lot of discussion in the thread on the vent kit and most believe they are vents that only pass air out under pressure only.



Sorry,,



Bill Davis