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Old 08-16-2019, 07:45 AM
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Default end carb venturi dripping

Hey guys - ive been working on the my 3x2. Was having gas dripping all over the manifold from middle carb and to a lessor degree the front one, also hard starting. I adjusted the all floats, replaced the n/s, added a fuel regulator, replaced some fuel lines and the fuel block. I no longer have any gas on the manifold which is great. car idles smooth too. But all of the sudden I have a new problem - I have dripping from the front carb at the venturi. You can see here:

https://www.youtube.com/watch?v=mzxYpx4BcYw

I checked the n/s again, and got a tip from Mike W to look at the checkball under the venturi. All look good. Do you guys have any recommendations on where I should be looking to stop that drip?

I know its been said, but Mike W is a great guy. I bought kits from him a year ago, and he was very responsive in offering initial thoughts just yesterday.

  #2  
Old 08-16-2019, 07:55 AM
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One other point, there don’t seem to be any vacuum leaks, hand over carb is fine. And, I did not have this Venturi dripping prior to me opening the carb to adjust float and n/s.

  #3  
Old 08-16-2019, 10:44 AM
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Tom Vaught Tom Vaught is offline
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Check the rod position between the rear carb and the front carb (on the passenger side).

When the engine is warmed up sometimes the rod will pull the front carb blades open slightly and you will get some carb drip.

Also it sounded like your engine was at a higher rpm vs normal idle. Another sign of possibly too much idle air. What was the rpm in the video?

Tom V.

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Old 08-16-2019, 11:00 AM
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Had one doing that at one time. Whoever rebuilt for the PO didn't get one of he seats tight. With a little "snugging" of the jet into the threads and problem solved.

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Old 08-16-2019, 03:09 PM
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Kenth Kenth is offline
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My tip from restoring Tripower carbs is to use the original style and size inlet valves.
Any other style have issues with flooding and/or restricted flow.
Also check the size on seats for 1966 factory sizes .120" in center carb and .086" in the end carbs.
1965 center uses a .100" inlet valve end carbs .086" as all other 1959-66 end carbs.

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  #6  
Old 08-16-2019, 11:15 PM
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Well I put the old n/s back in and the drip has gone away. I’m going to watch some this weekend and make sure.

On a related note, as anyone ever seen smoke come out of that little choke box on passenger side manifold? One car warms up I’ve got smoke out of that box.

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Old 08-18-2019, 04:44 PM
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Smoke can only be from paint burning off under the choke thermostat.

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  #8  
Old 08-18-2019, 05:08 PM
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Thanks Dick. It is strange as I have not painted anything. Maybe it was gas that needed to be burned off when I had my manifold dripping. Its just seems odd that it would still be doing that, as I have had the car on for a total of at least an hour over the last week. hopefully it will let up soon, seems to be subsiding.

With that said, I was able to go around the block today for about 15 minutes. No more leaks anywhere, no more venturi dripping. But, now I some how have lost some performance. Step on it and its just a bit lethargic, does not feel like all the carbs are kicking in full and that wonderful tripower sound is just a bit less. I don't know if the float setting could have that impact, but both end carbs had their drop set at 1.25 instead of 1.75. As I was going through the carbs I adjusted both the latter, which is spec I believe.. I have been wondering if both being off that much was more than coincidence, perhaps something the PO did to make this car happy. Anyway, Ill do my reading to see what I should be thinking about to solve for this power loss. constantly jumping through hoops.

I ordered an A/F meter and will have a bung welded in when I go to change the mufflers in next couple weeks. I suspect my a/f is off. the gas stink from the exhaust has always been a bit crazy.

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