Author Topic: PD41B/ PD42A  (Read 388 times)

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Offline Floshenbarnical

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PD41B/ PD42A
« on: July 22, 2023, 05:06:01 PM »
After getting sick of stripped holes I purchased a beautiful set of PD42As, as I had read they are interchangeable.

However, there is a small brass tube in front of the fuel line on the 42s, which isn’t present on the 41s.

Is this an air vent passage? Where should I run the vent to?
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Offline BenelliSEI

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Re: PD41B/ PD42A
« Reply #1 on: July 22, 2023, 05:12:38 PM »

Offline futility
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PD42A Carb Disassembly/Assembly
« on: April 15, 2015, 06:03:25 pm »

Look.up Member “Futility”. His PD42A post on April 15, 2015 is what you need.

Offline Floshenbarnical

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Re: PD41B/ PD42A
« Reply #2 on: July 22, 2023, 05:36:57 PM »

Offline futility
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PD42A Carb Disassembly/Assembly
« on: April 15, 2015, 06:03:25 pm »

Look.up Member “Futility”. His PD42A post on April 15, 2015 is what you need.

Thanks, I used that thread when rebuilding the original carbs. That thread has no info on this 2nd brass tube. I’m assuming that it might connect to the air cleaner but i don’t have one, so I’d like to know if I can clip it under the tank or something
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Offline madmtnmotors

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Re: PD41B/ PD42A
« Reply #3 on: July 22, 2023, 05:53:27 PM »
The 41B's each have an individual bowl vent in the form of a tiny hole at the base of the main carb body above each bowl. The 42A's have a shared vent that converge at the smaller brass tube on the #2 carb. You will notice that the 42A's have an additional crossover rubber tube between the carbs that the 41B's do not have that join all of the bowl vents. The smaller brass tube on the 42A in stock trim had a small rubber tube approx 6" in length that routed up to the top of the air cleaner where it was held in place by a small clip/bracket. Just run a hose up and to the rear, maybe zip tie it to the bottom of the frame tube.

EZPZ
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Offline Floshenbarnical

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Re: PD41B/ PD42A
« Reply #4 on: July 22, 2023, 05:59:59 PM »
The 41B's each have an individual bowl vent in the form of a tiny hole at the base of the main carb body above each bowl. The 42A's have a shared vent that converge at the smaller brass tube on the #2 carb. You will notice that the 42A's have an additional crossover rubber tube between the carbs that the 41B's do not have that join all of the bowl vents. The smaller brass tube on the 42A in stock trim had a small rubber tube approx 6" in length that routed up to the top of the air cleaner where it was held in place by a small clip/bracket. Just run a hose up and to the rear, maybe zip tie it to the bottom of the frame tube.

EZPZ

You’ve saved me again. Cheers. Float height is the same correct?
"All things change in a dynamic environment. Your effort to remain what you are is what limits you."

'77 CB750 SS

Offline denward17

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Re: PD41B/ PD42A
« Reply #5 on: July 22, 2023, 07:28:15 PM »
This might help....

Offline Floshenbarnical

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Re: PD41B/ PD42A
« Reply #6 on: July 23, 2023, 05:15:27 AM »
Oh my goodness these are 100x better
"All things change in a dynamic environment. Your effort to remain what you are is what limits you."

'77 CB750 SS