The video below includes such tips as polishing the secondary tubes to help with the O-ring seal.
1956 Ford Thunderbird and a Holley 4000
Before we begin the content on the Holley 4000 and the Tbird problems, you will want to read the first article in this series. It is one of the sections in a previous post here.
It has been a few weeks since I finished the work on the carburetor. My personal schedule in church ministry, operations to support people affected by the California wildfires close to home, and my friend's lack of availability have all delayed the repeat visit to the 1956 Ford Thunderbird. However, we were both glad to get back together on a Saturday afternoon. My friend kept discovering various problems that the previous owner of the car had tried to mask or just to make work in any way possible. One of these was a cobbled PCV system that included a piece of 1/2" hose that was both kinked and cracked. Another was the stripped threads on one of the vacuum advance pots. The spark plug wires had been replaced at some point but were now runing over the top of the valve cover and in the way of the throttle linkage.
The ECZ 9425A intake manifold sat for a few weeks waiting for its favorite carburetor.
Troubleshooting a carburetor is more than just "kitting" a carburetor. Meaning, while the carb is on the bench any problems that are being experienced must be addressed - leaks, surging, binding linkage, lean or rich conditions - these cannot just be recognized as trouble issues, but cause must be determined. For this particular carburetor there were several causes discovered. The plug that covers the needle and seat was leaking - this ended up being an uneven seating surface of the boss in the fuel bowl. The fix for this ended up being an O-ring instead of a flat nylon washer. The O-ring took up the space created by the slightyl uneven surfaces. The secondary tubes were leaking at idle - not only was this cause heavily abused O-ring bores (the Holley 4000 had been rebuilt a few times over the years and the washers staked multiple times but the secondaries should not have been active at idle. This ended being a linkage problem and bringing the all settings to initial tune and specifications remedied this problem (as the video clearly shows). There were some other items that could be mentioned, but most of them are covered in the video.
Stripped threads on the dual-vacuum advance distributor really hindered the effort.
There is part of me that wonders if I should just not have completely disassembled everthing and installed parts from a fresh Daytona Parts Company kit, but time and curiosity kept me from doing so. As the video will testify, the leaks were taking care of and the idle was certainly smooth. My friend had to chase quite a few problems. Unfortunately, the previous owner had installed a PCV system that was creating a vacuum leak, the one of the vacuum advance housings had stripped threads and could not be corrected during the afternoon, and there were issues with replacement fuel and vacuum lines purchased from CASCO. The sound in the video certainly points to a vacuum leak, and even though the repair on the Holley 4000 has certainly smoothed out the idle quality and the function of the carburetor there are still a variety of parts that my friend needs to replace or repair before we can drive the car and make the necessary final adjustments to the carb when it gets to operating temperature and we can put it under load. Hopefully that can all take place before the end of February.
The carburetor has been "through it over the years" but responded well to the repairs.
New Hot Rod Reverend Gear!
T-shirts, caps, mugs, stickers, and even coffee are available now in the Hot Rod Reverend store!
In case you missed it, there are quite a few brand new items in the store here on the website. Many of you have been asking for Hot Rod Reverend products like t-shirts or stickers, and thankfully the new logo ended up looking very good. All sales go to pay for the maintenance costs of the website which continue to rise each year. Selling merchandise enables me to keep from having those annoying advertisement banners pop up each time you visit. Thank you in advance for your patronage to the store!
The Hot Rod Reverend
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