T/A Six Pack Fuel odor under hood

[VillaTA]

Reposting this topic since the site went down. First time with a six pack setup. Getting fuel odor under hood during driving and after shut down. Not sure if there is something not vented or routed correctly. Not sure how much odor is normal, or too much. Also wondering where the hose nipples on the air cleaner base are supposed to connect to.

 

[70chall440]

One of those "nipples" attaches to the black filter on the drivers side valve cover.

As to the order, it is very hard to diagnose via the internet. If you are not used to classic muscle cars it could just be normal, however with a 6 pack it could be the bowl vent or perhaps a small leak some place.

 

[Daves69]

Also wondering where the hose nipples on the air cleaner base are supposed to connect to.

If your air cleaner base plate has it............

similar to a four barrel.......

The others look right for a non-vented center bowl.

 

[VillaTA]

My air cleaner has 4. One on driver side, two on the passenger side, and another at the rear on the passenger side. Seems like a lot.

 

[70chall440]

Post a picture

 

[Daves69]

Three off the bottom for drainage I do believe.........

https://nicksgarage.com/aircleaner/70_340-6_03.jpg

Mid page here............

Nick's Garage - Air Cleaner Identification

 

[VillaTA]

Pics detail the multiple nipples. I guess I should just cut a length of tube for the three “drains” and connect the upper rear to the breather on the valve cover?

 

[benguin]

PVC valve should be on the driver's side valve cover typically, with the PCV hose running around the back side of the carbs. Although this method does substantially shorten that hose.

The large breather cap then has a a short hose going to the nipple on the air cleaner on the passenger side.

Neither of those things should result in a fuel odor though. Possible the floats are set too high maybe?

 

[Tim Lynch]

Reposting this topic since the site went down. First time with a six pack setup. Getting fuel odor under hood during driving and after shut down. Not sure if there is something not vented or routed correctly. Not sure how much odor is normal, or too much. Also wondering where the hose nipples on the air cleaner base are supposed to connect to.

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View attachment 85887

How does it start ? I have three six pack setups two vented and one not vented center carb .Could be a fuel drip from center carb causing the gas odor .I sent my center carb to Holly for a rebuild and that did the trick ,my rebuild did not fix it ,they also flow test the carb .

 

[VillaTA]

It starts super easily. No issues at all.

 

[Cratos]

Check your float levels , pump connections and the weep hope on the pump.

 

[VillaTA]

Still getting this odor. Strong in the cabin tonight while driving as it was chilly when I took a ride and I had windows up. My garage smells like I spilled gas after I park the car. None visible under the hood on manifold or on carbs. I’m stumped.

 

[70chall440]

If you are smelling fuel that strongly then it is definitely leaking or coming out somewhere, pull the air cleaner and check around there. I guess its possible that its running so rich that essentially you are getting raw fuel into the exhaust.

 

[VillaTA]

If you are smelling fuel that strongly then it is definitely leaking or coming out somewhere, pull the air cleaner and check around there. I guess its possible that its running so rich that essentially you are getting raw fuel into the exhaust.

That’s what I originally presumed, however the raw odor is definitely located under the hood at the carbs. I just cannot see any fuel anywhere. Even right after i shut it down.

 

[Cratos]

did you check the float level? and your fuel psi. should be around 6 psi for street use

 

[VillaTA]

I’m no mechanic by any stretch. Any tips for how to check easily?

 

[Cratos]

you can drill and tap one of your brass t's for 1/8 NPT and put a 0-15 PSI Fuel gauge on it.

 

[70chall440]

If you have a stock or relatively stock fuel system to include a mechanical pump, you should not have excessive fuel pressure. My "bet" would be incorrectly setup and tuned carbs that are allowing far too much fuel into the engine.

All this said though, this could be a case of old car blues.... meaning that you are mistaking the fumes that car makes as designed with a fuel issue. Cars of that era did "smell" especially when compared to a modern car. I have to remind myself of this every time I deal with my (or any) vintage cars.

There is no way to diagnose this via the internet (until they invent "smellOvision"..) You need to find someone more familiar with older vehicles to give you their opinion, could be you are ok. 6 packs frequently run rich and this could be your issue.

 

[VillaTA]

The thing is, i just got it back from the shop I use and they are knowledgeable. They did some adjustments. Said that two of my vacuum lines were reversed. But the odor is the same as it was prior to sending to the shop.

 

[70chall440]

Did you ask your shop about the smell?