Dking76

How do you vent your fuel system? Do you use one of ports clamped with a rubber hose out the back of the tank?

Olds64

DKing, I moved your post to a new thread. You'll get better responses this way.

You originally posted in a thread on a 68 98. Is that what kind of Olds you have? There were different ways that fuel tanks were vented depending on year and model.

Dking76

It’s a 1967 Oldsmobile 98. Looking for the best way to vent the gas tank with a 2 line fuel sending unit. Thank you.

2blu442

I know the Cutlass and Toronado in 1967 had the breather hose ending behind the license plate with a plug & small hole in it or filter. I can take a picture of the Cutlass setup if that would help.

Dking76

That would be great. Is that hose coming from the back port from the fuel tank?

oldcutlass

There are 2 hoses that come out just behind the license plate and run to a plastic filter stuffed with cotton, attached to a clip above.

Pictures for illustration only

2blu442

Eric, I know the 1968-72 used the plastic filter on the two hoses. I don't have that on my 1967 Cutlass 4 door. Attached is a picture of what I have on the 4 door that I got with 47,000 original miles. I know the Toronado had a plastic plug with a hole in one hose. I believe these just have some kind of filter material pushed into the hoses. Two hoses above and to the left of the gas cap.

Dking76

Are these hoses coming out the back of your gas tank?

oldcutlass

The pictures are what was on mine when I got it, whether it belonged there who knows.

dfoelker

@Dking76 The 1967 98 has 2 vent ports in the front corner of the tank. The hoses from theses ports just end near the upper shock mount.



I hated my 67 98 always smelling like gas so I added the vent tube filter from a 68+ Cutlass (shown in a post above) to combine the two hoses to one:


I ran the combined hose into a fuel filter housing (with the filter removed) filled with charcoal filter material.



This worked great for a while, but I must have filled the tank too full at some point and gas worked its way through the vent hoses into the filter housing, saturating the charcoal filter material. Then it smelled like gas again. I removed the filter housing and just replaced it with a metal plug with a 1/8" hole drilled through it and mounted at the highest point I could. I made sure that the hose inclined back towards the tank, so if gas made ever its way into the vent again, it would flow back to the tank. This has been working well so far.

Dking76

Thank you for your feedback and pictures. This will help me out greatly.