Carbs and Gas Smell Options

[mmascari]

I have a 914 with a 3.0l six and PMO carbs. The gas smell is unbearable, especially when the car is in the garage. My wife is about to lose her mind. What do you carb guys do to limit this? Would running the engine with the fuel pump off, IE running out of fuel help with this situation?

[Osnabruck914]

If everything was correct, you should not be smelling gas. Find the leak and fix it.

Osnabruck914

[ClayPerrine]

Most of the carbed 914s have the charcoal canister system bypassed. Make sure it is hooked up and working.

[GregAmy]

That's not totally true; the float bowl is vented to the atmosphere. But the smell should certainly not be "unbearable".

Are you sure you don't have any leaks somewhere else? The fuel system should theoretically remain pressurized at your set point, 3-4 psi or whatever (though some fuel pumps will back-leak that pressure slowly).

Another common place for leaks - what made my D-Jet car "unbearable" in my garage - was rust holes in the tank sides where the wear carpet/felt retained moisture. I finally figured it out when fuel started seeping on my shoe soles, with a small puddle on the garage floor, any time the tank was over about 2/3-3/4 full. - GA

[ClayPerrine]

That's not totally true; the float bowl is vented to the atmosphere. But the smell should certainly not be "unbearable".

On a stock 914-6 the float bowl is vented into the air filter assembly. That is supposed to be part of the charcoal canister system, and will pull the fuel vapor into the carbs instead of venting it to the atmosphere.

This, however, does not apply to K&N water shield air filters. And I do agree, the small venting from the float bowls should not be unbearable.


And I agree with the tank rust issue. It started happening to Betty's 914 on the way home from Okteenerfest one year. Drove me absolutely bonkers trying to find the fuel leak. Ended up buying a new tank to fix it.

[mmascari]

Thanks for the replies. I will look for leaks.

[JmuRiz]

Let us know what you find, I've always found carb'd cars to smell of gas too. Mine is mostly burnt-off gas stink from driving into the garage.

My old 2.0/4 with carbs and my 356 both. The 356 you can turn the petcock off to drain the bowls...but you still have the smell of the car running until it runs out.

[dr914@autoatlanta.com]

something is leaking somewhere, maybe use a sniffer and see where

I have a 914 with a 3.0l six and PMO carbs. The gas smell is unbearable, especially when the car is in the garage. My wife is about to lose her mind. What do you carb guys do to limit this? Would running the engine with the fuel pump off, IE running out of fuel help with this situation?

[NARP74]

This also brings up the return line vs no return line debate. That pressure has to go somewhere...

[ClayPerrine]

This also brings up the return line vs no return line debate. That pressure has to go somewhere...

The factory pump for an original 914-6 looks like the one for the 914 with fuel injection, but it delivers a much lower pressure. The factory six had a return line that only came from the pump.

[rfinegan]

I had gas smell in may garage too, on a Carbed 75 914-4. I restored/ refilled the charcoal canister and the smells are controlled MUCH better. Check your gas cap for gaskets/seals too. Lots of smells and vapors in this area too
I found the gas tank produced most of the smells VS the carbs.
I hope this helps narrow your search

Is the smell stronger with a Full tank or less smell near empty?

[Root_Werks]

Don't forget carbs vent to the atmosphere, there will probably always be a little fuel smell. Best systems I've seen are factory aircleaner assemblies. Having simple K&N style filters on a six means you'll always sniff a little fuel.

As others have said, if it's that bad, you probably have a leak someplace. Probably something that is just enough to seep a little. I swear, one drop of fuel will stink up a 1,000SQFT!

(IMG:style_emoticons/default/icon8.gif)

[r_towle]

Todays fuel sadly evaporates much faster with the Ethanol component.

If storing a car, I would suggest adding a fuel shut off valve which you shut off once the car is park, yet still idling.
This will suck the remaining fuel out of the carbs.
Starting requires a bit longer, but you will take the smell away in storage.

Rich

[mlindner]

I would check all hose clamps to lines, filter, pump. My new pump and filter came together with hose and clamps....the provided clamps leaked badly. Its been two years now and no gas smells. PMO's, single fuel line, low pressure fuel pump, inline fuse.

[BillJ]

Gas cap as well. If that seal is not working right can definitely leak fumes. I had this issue once. New gas cap fixed it

[r_towle]

Fun fact.
The evaporation "system" on a stock 914 expansion tank (the tank at the filler location) is just a hose the routes down behind the tank and out onto the ground....into the atmosphere.

Its a vapor leak that can/will smell up a garage.

rich

[emerygt350]

Yeah, look around. I just pulled mine out to do some seat of the pants tuning and was thinking to myself I was running really rich. Popped the hood to check my mps and fuel pressure and low and behold, the injector rail on the passenger side was weeping. I cried a little too.

(Poorly installed clamps by the current owner)

[r_towle]

Yeah, look around. I just pulled mine out to do some seat of the pants tuning and was thinking to myself I was running really rich. Popped the hood to check my mps and fuel pressure and low and behold, the injector rail on the passenger side was weeping. I cried a little too.

be happy you found it this way versus a fire.

[930cabman]

Better get things fixed quick, or you may find yourself and your stuff at the curb.

I have had carb'd cars for years and never had the gas smell (IMG:style_emoticons/default/wacko.gif)

[nditiz1]

As stated carbs vent to the atmos,

I have PMO's on my 6 conversion - no char canister, vent goes from tank to engine compartment

I also have PMO's on my 911SC. This one smells even worse as it likes to run rich. Sometimes the fuel smell will seep into the main garage and my wife hates it. No leaks on either of my cars. Best thing I do is leave the door open a little after I pull it back in.

Agree with running the bowls empty if you really cant bear it.