Author Topic: Hose Connections from Air Box and from Carb # 2  (Read 873 times)

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Offline Lloyd

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Hose Connections from Air Box and from Carb # 2
« on: November 27, 2017, 10:00:38 am »
Hello, I am new to this forum and this is a new Bike for me so I have a few questions.

1. to start since I am replacing Carb. Pods for the Original Air-Breather. The original air breather has a hose connection top center, I do not know where this connects, assume it is a Vacuum Connection but could not find where, after looking further I found a hose with no connection going to the Oil Tank I believe, that must be like a PCV Valve Connection to the crankcase or something like that. I did find a hose that looks like it is going up to the Oil Tank that is not connected - Yellow Hose with a ring connector but not connected to anything.

2. there is also a small hose coming from carb # 2 and is loose with a broken barb inside, looks like another Vacuum Connection?

in my manual I see hose connections to the Carb and Solenoid that includes a check valve.

Any assistance will be greatly appreciated


Offline Lloyd

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Re: Hose Connections from Air Box and from Carb # 2
« Reply #1 on: November 27, 2017, 10:33:50 am »
Forgot to add my Bike Data:

1978 Honda 750 4 SOHC
Black, Gorgeous Bike needing a little TLC but in excellent condition.

Online 754

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Re: Hose Connections from Air Box and from Carb # 2
« Reply #2 on: December 05, 2017, 04:53:49 pm »
77/78 has an air canister thing under the aircleaner, uses more hoses.
You can ask these questions in sohc/4 bikes, you will get help faster.
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Offline madmtnmotors

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Re: Hose Connections from Air Box and from Carb # 2
« Reply #3 on: December 05, 2017, 05:10:08 pm »
The 77/78 K and 75 thru 78 F models use a vapor separator canister under the battery box. The valve cover vent hose runs to the upper connection on this vapor separator, the middle connector on the separator connects to the top of the air box, and the bottom connector on the separator should have a hose that runs around and under the front of the swingarm then towards the rear with a plug in the end of it. Periodic maintenance indicates removal of the plug to drain any accumulated moisture. This hose was originally secured to the right muffler bracket. There should be some parts fiches that show this assembly as well as some manuals.

Or you could just connect the valve cover vent to the airbox.


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