Gas smell....need some help!

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ORO62

Well Known Member
Hello gents! It's been a while since I posted last and I've made some major progress on my engine. Had the carburetors rebuilt, changed spark plugs, wires, rotor, cap, and the shop did some minor tuning. I also changed the gas cap because the car was wreaking of gas while parked in our garage. The wife was furious so I ended up having to park outside for a few days prior to all this work.

Well, here we are after several thousands of dollars spent and the stench of gas is about half what it was before. It's tolerable to the point that I'm parked inside, but we have all the windows open constantly because of the smell. Shop indicated they didn't find any gas leaks, so I'm wondering what it could be. Smell is mostly coming from under the hood. Car has not been run in over a week.

I've thought about adding an evap carbon canister from the vapor outlet on the carbs. Has anyone done this? Any other ideas about what could be going on? I know that an old car is gonna stink, this is far beyond that smell. Please help!
 
wristpin

wristpin

Well Known Member
Any indicators of fuel line leaking? Line could be rusted enough that liquid wicks through the rust but not enough to drip. Check every inch of the fuel line. It could be rubber portion of fill line or vent. Have you looked down the carb to see if fuel is seeping in past fuel needle valve into carb?
 
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ORO62

Well Known Member
wristpin said:
Any indicators of fuel line leaking? Line could be rusted enough that liquid wicks through the rust but not enough to drip. Check every inch of the fuel line. It could be rubber portion of fill line or vent. Have you looked down the carb to see if fuel is seeping in past fuel needle valve into carb?
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I've checked the lines and the pump, but don't see any visible leaks. Shop said the same. I've read that something as small as a pin hole could cause this so I'm not really sure what to do on that end. I've been told that you can pump smoke into the filler neck and look for leaks in that way, but I'm not sure if that's harmful for the engine at all.

Will have a look at the carb tomorrow. Thanks!
 
409gang

409gang

Well Known Member
Supporting Member 1
My Corvette lost about a 1/2 tank of gas one year while in the garage and I never noticed a smell as it was a very small leak that was dripping on a seam in my garage floor. It wound up being the rubber hose between the frame and the fuel pump, I would check all rubber hoses or replace them as they are probably quite old and could use replacing anyway. If you think your carb is leaking down into the engine make sure you check your engine oil for gas before you start it up.
 
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427John

Well Known Member
If this car is one with the 3/8 fuel line in 3 pieces that means at least 4 short sections of rubber hose underneath the car and unless they have been replaced in the last decade or 2 then they are probably non ethanol resistant rubber fuel line,any or all of those could be leaking or seeping,another possibility could be the top of the fuel tank could be rotted with pinholes if this were the case you would get the gas vapor with no evidence of liquid leaking.My son recently had to replace the tank in his old bronco due to it started leaking,when he got the old tank out and we saw the topside it was full of pinholes.
 
59apachegail

59apachegail

Well Known Member
One of my friends had the exact same problem. After chasing his tail and spending a ton of cash he found out the problem wasn’t the car at all.

Have you considered a bathroom extraction fan for your garage? You can probably get something that moves 150 cubic feet of air for $100 or so.
 
Jayz63

Jayz63

Well Known Member
What kind of car is it. With some of my other impalas there is a rubber fuel line that connects the fuel tank sender unit to the first part of the fuel line. Then there is another rubber line that is by the rear end that attaches to the longer line that goes to the fuel pump. I believe your problem will probably be found there. Also if you haven’t checked your clamps for the filler neck those can leak due to being rubber hoses as well.
 
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ORO62

Well Known Member
409gang said:
My Corvette lost about a 1/2 tank of gas one year while in the garage and I never noticed a smell as it was a very small leak that was dripping on a seam in my garage floor. It wound up being the rubber hose between the frame and the fuel pump, I would check all rubber hoses or replace them as they are probably quite old and could use replacing anyway. If you think your carb is leaking down into the engine make sure you check your engine oil for gas before you start it up.
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That's fair advice. Most of the other hoses in the car need to be gone through so that makes sense.
 
O

ORO62

Well Known Member
427John said:
If this car is one with the 3/8 fuel line in 3 pieces that means at least 4 short sections of rubber hose underneath the car and unless they have been replaced in the last decade or 2 then they are probably non ethanol resistant rubber fuel line,any or all of those could be leaking or seeping,another possibility could be the top of the fuel tank could be rotted with pinholes if this were the case you would get the gas vapor with no evidence of liquid leaking.My son recently had to replace the tank in his old bronco due to it started leaking,when he got the old tank out and we saw the topside it was full of pinholes.
Click to expand...

That is in fact my situation with small sections of rubber hoses. Definitely going to hit those first. Thanks!
 
O

ORO62

Well Known Member
59apachegail said:
One of my friends had the exact same problem. After chasing his tail and spending a ton of cash he found out the problem wasn’t the car at all.

Have you considered a bathroom extraction fan for your garage? You can probably get something that moves 150 cubic feet of air for $100 or so.
Click to expand...

Yes this is something else I'm working on. My home was built 6 years ago so the garage isn't vented because who would buy old cars right? Sigh. Working on getting some vents installed and maybe a fan as well.
 
O

ORO62

Well Known Member
Jayz63 said:
What kind of car is it. With some of my other impalas there is a rubber fuel line that connects the fuel tank sender unit to the first part of the fuel line. Then there is another rubber line that is by the rear end that attaches to the longer line that goes to the fuel pump. I believe your problem will probably be found there. Also if you haven’t checked your clamps for the filler neck those can leak due to being rubber hoses as well.
Click to expand...

It's a 62 imapala, and yes that sounds familiar. I'm thinking of just going through and changing all the hoses out. Thanks!
 
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