Gas smell

[dave`12]

I finally moved and have a garage. Of course the C-10 lives in there and my DD is outside

Anyway, I never noticed because it sat outside, but man, the gas smell in the garage is overpowering.

I have the 1967, but I think a PO must have replaced the tank, I think it may be a couple years newer.

I have a vented cap. There is another vent that was coming off the tank. I ran a hose from that out under the vehicle.

Anyone know how I can get rid of the smell? Are there filters or something that should be on the end of the hose I put under the vehicle. Should I get a vented cap? I'm sure they didn't smell like this from the factory!

Thanx

[dmjlambert]

Originally Posted by dave`12

I have the 1967, but I think a PO must have replaced the tank, I think it may be a couple years newer.

I have a vented cap. There is another vent that was coming off the tank. I ran a hose from that out under the vehicle.

I'm thinking the vented cap should be enough, and the other vent coming off the tank needs to be plugged. Vented caps don't let out a lot of fumes unless there is pressure build up from the sun shining on the truck after you park it. The vented cap's function is mostly to let air into the tank as you use up the gas.

[68 P.O.S.]

Replacing the gasket for the sending unit in the tank often helps with this.

[sick472]

The newer systems would have a vent line coming off the the tank that snakes up the hollow area of the cab on the passenger side then back down and out the floor (this acts like a trap in a sink drain to keep fuel from coming through the line)...then snakes up to the engine bay and be connected to to a charcoal canister. Theses tank systems would have a non-vented cap. All the swelling and contraction of the gas during temp changes would suck and blow through the canister (not the cap) which is supposed to take the smell out of the vapors. Here's a thread with good diagrams...

http://67-72chevytrucks.com/vboard/s...d.php?t=662158

Edit: I'm betting your garage gets hot during the day and much cooler at night causing alot of the 'sucking and blowing" of gas fumes from the tank.

[Minkota]

I had same problem on my 67, it turned out the 6 " rubber hose under truck that goes from hard tank line to to hard line that runs toward the motor was leaking due to ethanol.

[bry593]

Check your fuel pump to see if it is wet after a drive. There is a weep hole and a small crack in the diaphragm will allow gas to seep out of this weep hole.

I had this problem and it was not enough of a leak to be obvious. Didn't even leave a wet spot on the floor. But it would stink to high heaven in the garage an hour after I parked the vehicle.

[siggyfreud]

Install a charcoal/vapor canister. The fuel tank vent line runs to it, and then into the vacuum system.

Vented caps are going to do nothing but vent fumes into the atmosphere (ie your garage).
You want a close looped system that still allow tank pressure to be displaced when needed. That's what will help get rid of gas smell.

[davischevy]

My wife has been complaining for years about the gas smell in the garage. I think it comes with the truck.

[dmjlambert]

I have a 1969 truck with vented cap and park in the garage. No gas smell. I do not have "another vent that was coming off the tank". The vent in the cap is used to let air into the tank, not to let any fumes out. 1969 was not a year when they had the tank vent tube and charcoal canister, that didn't come along until later years.

[mr48chev]

Even though it is inconvenient at times it is best not to fill the tank on your truck just before you head home with it and leave some space in the tank for expansion.

With ethanol it is wise to check your fuel system over pretty regular for damaged rubber parts. Plus make sure you get new hose rated for it.

[BigBird05]

I got a van for free that had sat for 2 years after they towed it home. It pumped gas but had no pressure. The hose inside of the tank was rotted out from ethanol gas. $2.00 hose and it started up and ran well.

[mr.precision]

Originally Posted by Minkota

I had same problem on my 67, it turned out the 6 " rubber hose under truck that goes from hard tank line to to hard line that runs toward the motor was leaking due to ethanol.

Same here on my '67. An easy fix.

[68Gold/white]

I just helped a friend purchase a 71 C-10. Original California pickup. It's in no spectacular condition. Took him to look at it (I had known about it for a long time, before it came up sor sale). It started and drove, OK. 350 engine, TH350 trans...ANYhoo. It has 3 rubber lines coming from the gas tank, to the steel lines on the frame. I'm sure they were original, they were seeping gas!!! Never seen that!!! THey got changed first!!!

Some carbs come with a vent in the fuel bowel. It has a small rubber cover that keeps dirt out. The vents went away in the later 60's

[jabborabbo]

I’ve had this issue twice - first time the carb wasn’t tight on the intake manifold and also gas was seeping out between the bowl and the horn. Second time (which resulted in a much stronger smell) the fuel pump was weeping/leaking.

[dave`12]

Finally got around to replacing the cap with a non vented one. (By the way, the P/O had vented it with a drill

Anyway, the smell is much better, but still present. I have a hose coming off the top that goes under the frame. I'm afraid to plug it??

By the way, turns out that the tank must be from a later model. The cap that fit was for a 1972 C-10.

Thanx

[HO455]

I would replace any hose more than 5 years old. A hose may not leak but it can allow fumes to pass through the hose. I would suggest checking the tank sender gasket too.
One or two drops of fuel will stink up the average garage for a day or two. You can stop that from happening like I did. Just pour a cup or two of Hypoid gear lube on the floor.

[tdangle]

sniff around, could be a bad seal on the gas cap, sending unit, Double check or replace the hose under the cab joint the 2 metal lines, check the fuel pump and hoses to it.

Also do you have an open element air cleaner? I was having issues with my quadrajet (long gone now) evaporating the fuel in the bowl or maybe leaking? and the open element didn't contain the odor like a full air cleaner assembly will.

[Wrenchbender Ret]

Check around the fuel inlet at the carb. A tiny drip can produce a lot of smell when it drips on the hot engine.
George

[LEEVON]

I fixed this problem on my '50 truck, because my wife hated the garage smell. I removed the vented cap for a non-vented one. I took the vent line from the filler neck from my behind the seat tank and looped it up into the cab corner, then through the cab floor, then down the frame rail to the rear, where I put a regular fuel filter in line then a differential valve on the end. Smell went away.