Dead cylinder help

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Jonathan Halpern
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Re: Dead cylinder help

#46 Post by Jonathan Halpern »

Yes, that is the plan for sure. I suspect idle circuits simply because it sat too long. It was okay when parked...

Rusty Ferrell
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Re: Dead cylinder help

#47 Post by Rusty Ferrell »

Johnathan, while she idling coke the carb by placing your hand over the Venturi the high vacuum created will sometime clear a jet.
Happy Easter to all 6ers out there
Rusty

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Jonathan Halpern
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Re: Dead cylinder help

#48 Post by Jonathan Halpern »

Hi Rusty,

I did actually try that. Makes a surprising amount of vacuum, it wanted to suck my skin off. Didn’t help unfortunately. Thanks for the tip, its a good one.

Jonathan

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James Rowe
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Re: Dead cylinder help

#49 Post by James Rowe »

Well, did you ever figure it out?

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Jonathan Halpern
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Re: Dead cylinder help

#50 Post by Jonathan Halpern »

Actually, no... sad but true. Its sitting in the garage on a tender. I was actually thinking of getting back on it this week. I’ve been distracted with other cars.

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Dennis Vogel
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Re: Dead cylinder help

#51 Post by Dennis Vogel »

David Jones wrote: Sat Sep 28, 2019 7:46 pm you could swap carbs side to side and do not worry about the linkage, just see if it will run at idle and if the problem transfers.
I want to thank David for sharing this tip. It was not obvious to me, nor the couple people I talked to, to try this. It helped me trace a "cylinder issue" to my carbs. When I swapped the carbs side to side, the issue followed the carb.
1960 356 S90 Sunroof Coupe
1970 914-6
2014 Carrera S

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Jonathan Halpern
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Re: Dead cylinder help

#52 Post by Jonathan Halpern »

Old thread but I finally got back around to it after focusing on some other cars for a long while. Drained the stale fuel, blew out the lines, opened up the Zeniths and cleaned everything as well as installing a rebuild kit. Still had the same issue. Went back into the Zeniths and finally found the issue- a blockage in the passage between the idle jet and idle air jet on cylinder 3. Some cleaner and some blasts of air and some black crud came out. Looked like a small piece of plastic. Back up and running!

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Mike Wilson
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Re: Dead cylinder help

#53 Post by Mike Wilson »

👍

Mike
Mike Wilson
Lomita, CA
'63 B coupe

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Thomas Sottile
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Re: Dead cylinder help

#54 Post by Thomas Sottile »

Hoo Ras

Dave Erickson
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Re: Dead cylinder help

#55 Post by Dave Erickson »

How old is the distributor cap? Back when I did tune ups for a living, I used to occasionally see distributor caps that had faults (usually cracks that were almost invisible). Sure sign is a line of carbon on the inside of the distributor cap.

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Wes Bender
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Re: Dead cylinder help

#56 Post by Wes Bender »

Issues that seem to be carburetor related are often the fault of a distributor, but in this case it was the carb. Glad you got it fixed. I had one pesky problem that was intermittent and nearly drove me nuts. Everything would run fine and then suddenly one cylinder would start to miss. If I backed off the throttle to stop and check it, the problem would go away, only to return at some future time and place. I pulled the main and idle jets on the Zeniths several times and blew them out. Finlay, on one jet cleaning exercise, I noticed something funny in the #3 main jet. It turned out to be a small piece of paper towel or other similar fiber partially blocking the jet. Blowing through the jet opened it, but it didn't come out. Blowing the other way caused it to partially block the jet. Turned out there was a small burr in the machining for the large diameter portion of the jet and the fiber was hung up on it. I reamed it out with a drill bit to smooth the burr and my problem went away. Turns out the fiber would stay hidden until there was demand for enough fuel to cause it to partially obstruct the jet. Once the fuel flow was sufficiently reduced, it went back into hiding.
Some days it's just not worth chewing through the restraints.....

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Jonathan Halpern
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Re: Dead cylinder help

#57 Post by Jonathan Halpern »

Wow! In the end, it’s usually something simple. The number of hours it takes to find the simple problems is another story.

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Wes Bender
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Re: Dead cylinder help

#58 Post by Wes Bender »

At the time it seems frustrating, but in the end it is all part of the experience of owning these little jewels.
Some days it's just not worth chewing through the restraints.....

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Thomas Sottile
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Re: Dead cylinder help

#59 Post by Thomas Sottile »

Think how much you have learned, that knowledge will help in many ways

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