fuel smell from 383 engine

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Early a body

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Have an issue with my 66 charger 383 4 barrel automatic.

Haas a strong fuel smell , not from the carb but from the exhaust when running. My initial timing is set at 20 curved not to exceed 35 degrees. Carb is a newer edelbrock 650 cfm.

I am used to the older cars smelling but this one is really bad.

When I bring the initial up to 25 degrees the smell is gone but the "off the line torque" is diminished. Started begins to kick back so I know I am as far as I want to go on the initial timing.

I am curious why the off the line torque would drop off. It seems I am burring all the fuel which would help with the torque.

I cannot remember what cam is in this motor but is is a mild cam. also have 915 heads.
 
For what its worth..
I also had a brand new, out of the box Edelbrock carb on my 383. Couldn't get it to run right, had a constant backfire, seemed lean.
An old time Mopar mechanic swore the carb was no good...
Had the brand new carb rebuilt, just to show him and he was 100% correct, never ran better.
No more backfire and more power.
New doesn't always mean good.
Joe
 
Is it a raw fuel smell or too rich, black smoke exhaust smell?

Today fuel is very damaging to old rubber hoses and gasket and degrades them over time. It also has an awful skunky smell. How old is the fuel like from the pick to the line at the tank, pick up seal and filler seal?
 
Early a body said:
When I bring the initial up to 25 degrees the smell is gone but the "off the line torque" is diminished. Started begins to kick back so I know I am as far as I want to go on the initial timing.
Click to expand...
This says to me that since you have to start the fire so darned early,to burn all the fuel inside the chamber, that there is something going on in there that should not be.
I'm guessing there could be a dozen things that could cause that situation, here are some;
Cold engine, and or choke on,
rich, or very lean idle,
leaking PV or pump circuit, plugged airbleeds, or high fuel level,
poor low-powered ignition system or fouled plugs
valves not sealing, especially exhausts
big cam/low cylinder pressure/faulty cam-timing,
Ok that's fourteen already.

You're gonna have to mount a systematic campaign to figure it out.
 
dano said:
Is it a raw fuel smell or too rich, black smoke exhaust smell?

Today fuel is very damaging to old rubber hoses and gasket and degrades them over time. It also has an awful skunky smell. How old is the fuel like from the pick to the line at the tank, pick up seal and filler seal?
Click to expand...


It smells like the fuel is not all burning up in the chamber, I think I confirmed this by bringing the timing up and the smell goes away.
 
Eddie carbs are known to not run right out of the box. Only 1 in 10 is wet flowed at assembly. By a reconditioned one which is one that was returned and fixed, then wet flowed before resale. Jegs has them.
 
Another thing to check- the fuel pump! When the diaphragm starts to go bad, it may leak through a weep hole in it's housing or dump gas directly into the engine. To check- check for leak at fuel pump housing and smell your engine oil to see if there is a strong gas smell.
 
All good suggestions but no one has asked the 64 dollar question. Did it ever run good?
 
I'm probably way off base here, I have had ethanol gas that was in the tank awhile, treated with stabil, the exhaust stunk so bad you have to change your clothes!
At first I thought the air settings were the cause but I ended up right back in the same place. I rebuilt the carb with no change. I drained the tank and it smelled old. The proof came when I put it in the mower and made that stink too. Any chance you have old ethanol gas in it? I understand it only takes a few weeks to start to separate.
Good luck with the Charger.
 
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