Fuel leaking from carb
#21
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Lars
Last edited by lars; 02-12-2019 at 04:07 PM.
#22
An old timer once told me to never use a cloth towel or rag to cover, or stuff one in, an engine opening.
He said that strands from a cloth towel could do serious damage to an engine if some get inside.
He always used paper towels as he said the paper fibers would do no damage in the oiling or water systems and would simply burn if they got into the combustion chambers.
Sounded reasonable.
He said that strands from a cloth towel could do serious damage to an engine if some get inside.
He always used paper towels as he said the paper fibers would do no damage in the oiling or water systems and would simply burn if they got into the combustion chambers.
Sounded reasonable.
#23
Burning Brakes
I love my Tri-power set up enough to give up 30hp compared to the single Holley and Dart intake, but it's a pain. Lars, you sir are an inspiration and a gluten for punishment
#24
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#25
Burning Brakes
I don't know you well enough to speak on the Carbs question but as far as the other maintenance item you mention
Had I known you were so close to Fort Collins I would have asked for Brew Pub suggestions (I'm here til Sat Afternoon this trip)
Had I known you were so close to Fort Collins I would have asked for Brew Pub suggestions (I'm here til Sat Afternoon this trip)
#27
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Found a whole list of problems and issues, so the rebuild was much needed. The fuel leak at the accel pump was caused by the pump housing screws being loose (finger-tight) - the diaphragm was not ruptured as some had suggested. Other issues found:
Fuel line at the center carb is damaged, and will be rebuilt as part of the rework process.
Carbs disassembled, cleaned up, and ready for (correct) assembly:
Lars
- Secondary floats were bottomed-out on their adjustment
- Stripped threads and loose hardware throughout - vacuum diaphragm housings were not sealed against the carb bodies
- Incorrect and damaged hardware
- Only 1 carb (end carb) had a fuel filter, and it was missing the filter spring (all fuel bypassing the filter)
- End carbs had the stock "brown" (i.e. "very heavy") secondary springs installed, preventing full secondary opening (if the secondaries opened at all due to vacuum leaks at the carb body)
- Badly misbalanced idle mixtures
- Accelerator pump discharge nozzle seals never installed by previous builder - massive accel pump fuel leak bypassing nozzle
- Extremely lean (leanest possible) accel pump cam installed ("white" cam), producing poor accel pump shot for only partial throttle travel
- Secondary float springs installed backwards, forcing floats "down" instead of assisting "up." This may be why the secondary float adjustments were jammed into the extreme "low" position and bottomed-out.
- Choke intermediate rod seal plate in airhorn altered and damaged - not "floating" and causing choke to intermittently not close
Fuel line at the center carb is damaged, and will be rebuilt as part of the rework process.
Carbs disassembled, cleaned up, and ready for (correct) assembly:
Lars
Last edited by lars; 02-21-2019 at 09:56 PM.
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tfringo (12-19-2020)
#28
Burning Brakes
Lars, Holley makes a Bowl Inlet Fitting that allows use of 3/4" Wrench, you may want to check these out for non-NCRS guys. Much nicer for folks that prefer easier over original. I posted more pics a while back for DUB, he wanted to see how well the Wrench fit.
#29
Drifting
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2018 C3 of Year Finalist
Maybe I am wrong but I think yours are origonal ,and not available any more and the ones Lars is showing
are what is available from holly now. I also think they are metric.
are what is available from holly now. I also think they are metric.
#30
Burning Brakes
Actually mine are current Holley pieces ( I buy them at a local Carb Shop), P/N 26-162 The Bowl Inlets are not Metric Thread or Wrench sized, I have some very early 60's Bowls and they haven't changed the Thread Dia. or Pitch it's 7/8-20.
#31
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I just updated and added to the "problems" list in my post# 27.
The original Holley inlet fittings have the 1" hex with 7/8-20 thread. Other than the odd-ball 9/16-24 "Acorn Nut" fuel inlets used on some of the GM OEM Holley carbs in the mid '60s, the 1" hex 7/8-20 thread inlet is the only inlet nut that has been used by Holley (disregarding the "Banjo" fitting carbs). Due to many complaints about the 1" wrench access, Holley is offering the revised inlet nuts with the 3/4" wrench hex, retaining the standard 7/8-20 threads, as a retrofit item. There are no metric Holley inlet nuts. I've never had an issue with the standard 1" nuts, but I do install the "retrofit" 3/4" inlets upon request.
Lars
The original Holley inlet fittings have the 1" hex with 7/8-20 thread. Other than the odd-ball 9/16-24 "Acorn Nut" fuel inlets used on some of the GM OEM Holley carbs in the mid '60s, the 1" hex 7/8-20 thread inlet is the only inlet nut that has been used by Holley (disregarding the "Banjo" fitting carbs). Due to many complaints about the 1" wrench access, Holley is offering the revised inlet nuts with the 3/4" wrench hex, retaining the standard 7/8-20 threads, as a retrofit item. There are no metric Holley inlet nuts. I've never had an issue with the standard 1" nuts, but I do install the "retrofit" 3/4" inlets upon request.
Lars
Last edited by lars; 02-21-2019 at 09:59 PM.
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tfringo (12-19-2020)