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Guest Rich's 56

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Guest Rich's 56

Does anyone else have a strong emissions odor? I recently installed a new carb from "Larrys T-Bird" (btw this is not a paid endorsement lol.) but It really smells. I'm going pull the plugs tomorrow to get an idea of whats going on. My 2nd. question is can anyone tell me the needle valve settings for the idol screws and warm idol settings and of course the cold idol settings.
292 CI Holly 4bl 

 

Note we have always been very happy with Larry"s

Edited by Rich's 56 (see edit history)
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As far as the idle mixture screws are concerned, there is no "setting".  They are to be adjusted to where the car runs the smoothest.

 

Get the car to operating temperature and turn the screws clockwise and counterclockwise to find the smoothest point.

 

Regarding the hot and cold idle setting, do you mean RPM?

 

 

 

 

Does anyone else have a strong emissions odor? I recently installed a new carb from "Larrys T-Bird" (btw this is not a paid endorsement lol.) but It really smells. I'm going pull the plugs tomorrow to get an idea of whats going on. My 2nd. question is can anyone tell me the needle valve settings for the idol screws and warm idol settings and of course the cold idol settings.

292 CI Holly 4bl 

 

Note we have always been very happy with Larry"s

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Guest Rich's 56

I runs pretty smooth now, but it smells really rich. It smells so bad when done tinkering I have to go change clothes and shower!

 

I work on oil fired furnaces all day and don't come home smelling like fuel oil.  Thanks for the reply!

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  • 2 weeks later...

I think you speak about the Holley "tea pot"-Carb ?

I had try to fix it and read so many things from gearheads about it...

These guys, and myself mean its a faulty construction..

On my girls '54 Bird i had it ,after many Tests, change over to a 500cfm edelbrock with manual choke (because of the 6V system), with an upside down mounted adapterplate and a 10"(if i remember right) Airfilter on it.

The oem parts are now stored and the car runs great with also a much better mileage .

m2c

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I don't know what carburetor you have but I do have some experience working on carbs in different iterations on many different cars. Seems to me that your questions about setting idle screws would have nothing to do with the "smell" of your exhaust. If the mixture screws (needle & seat) are out too far it would run really rich and you would smell a lot of gas. The way I learned to do it was to turn the screws all the way in ( just snug - not tight) then back them out some certain number of turns. ( usually around 3-1/2 turns ). Start the car.to get it warm. Turn in one of the screws until you get a "lean roll" then back it out a quarter to half turn. Then do the other screw. I would do this back and forth a couple of times. I would set the low idle speed using a tachometer then set the choke. I would set the choke by rotating the cover until it just started to close then back it off just a hair so that the butterfly is not trying to close because the engine is warm and it (the butterfly) should be wide open. I would then let the car cool down and recheck the choke and idle speed (high & low) settings.

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I think you speak about the Holley "tea pot"-Carb ?

I had try to fix it and read so many things from gearheads about it...

These guys, and myself mean its a faulty construction..

On my girls '54 Bird i had it ,after many Tests, change over to a 500cfm edelbrock with manual choke (because of the 6V system), with an upside down mounted adapterplate and a 10"(if i remember right) Airfilter on it.

The oem parts are now stored and the car runs great with also a much better mileage .

m2c

 

 

Never heard of a 54 Thunderbird. 

Edited by paul2748 (see edit history)
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  • 2 weeks later...

It would be MUCH easier to offer an answer if more information were given. WHICH Holley 4-barrel??? The 1956 was originally the "haystack" design (Holley type 4000), but the design changed in 1957 to the Holley type 4150 which blew power valves about as often as a Baptist minister says grace at the table! Lots of 1956 engines retrofitted with the type 4150. The OP mentioned a new carb. I haven't seen a new 4000 in decades! But there are lots of aftermarket 4150 and 4160 carbs available new.

 

Some general observations:

 

(1) The "cold" idle mixture settings, and the "hot" idle mixture settings are the same.

(2) Idle mixture settings effect the A/F ratio significantly ONLY at idle and slightly higher.

(3) Too rich a mixture should blow black smoke

(4) Too lean a mixture will REALLY stink (like rotten eggs)!

(5) Too rich could indicate ignition issues (90 percent on most vehicles, 98 percent on 1950's Fords).

(6) Too rich could also indicate too much fuel pressure, or a blown power valve (very common issue on Holleys).

 

Diagnosis, in order:

 

(1) Compression

(2) Ignition

(3) Fuel delivery system

(4) Carburetor

 

And lastly, had we rebuilt your carburetor or sold you a new one, and you had issues; we would want you to discuss the issue with us. Have you posed the question to the vendor?

 

Jon.

Edited by carbking (see edit history)
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  • 2 weeks later...
Guest Rich's 56

Yes It is this carb. thank you all for the replies. turned out to be the smell of old fuel. Now the motor is coming out for a rebuild. there were compression issues.

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Guest Rich's 56

Yup checked the rings.. found a piston with a crack in it. looks like a previous lash problem. the valve had been replaced b-4 I bought it.. not a pretty sight.

3 pistons had compression @135 psi

2@ 110 psi

2@ 118 psi

And the last was zero with a heck of a lot of blow by..

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