Mystery hose?

[antijam]

I've discovered what appears to be a vacuum hose in the engine bay of my '71 that is not connected to anything. Arrowed in the picture below....



It appears to originate at the vacuum tank and runs up and forward (I've placed it on the master cylinder for clarity) and is plugged with a bolt. All the vacuum operated components on the car seem to work so I'm wondering what its purpose is/was.

Anyone have any suggestions?

 

[Oneball]

There’s so many of them, you’ll probably need to follow them all and see which one is missing.

 

[Daytona Vette]

Follow the radius of the tube to see where it ends up

 

[Roscobbc]

Did your car originally have vacuum washers? that could be just the right length to reach the wiper motor behind the distributor.

 

[Dazaa]

This should help

 

[antijam]

Thanks for your response guys. Although I said that everything that should work does, I forgot about the screenwashers. The wiper door and the wipers act as they should but the washers don't. I'm still grappling with the complexities of Chevy's vacuum/electrical systems (don't you sometimes feel that when something would work satisfactorily with 2 or three parts, Chevy thought that it would work better with 20?). My car certainly seems to have the original washer system Ross, that in my innocence I thought was electric - there are certainly vacuum pipes connected to all the obvious ports - am I perhaps missing something?

 

[Roscobbc]

Can help on that one. Someone converted to electric years ago on mine.

 

[Oneball]

Your washer system is just electric, works off a cam driven by the wiper motor. No vacuum fittings.

 

[antijam]

Your washer system is just electric, works off a cam driven by the wiper motor. No vacuum fittings.

Thanks Tim. I realised after I posted the picture the tubes connected to the pump are of course screenwash fluid pipes, not vacuum lines ...doh

 

[Oneball]

Vac hoses for a ‘69

 

[Dazaa]

You said it comes from the vacuum canister right? Which port?

 

[johng]

Are you sure it comes from the vacuum canister and not the vapour canister? (as per Dazaa's previous picture)

 

[antijam]

Are you sure it comes from the vacuum canister and not the vapour canister? (as per Dazaa's previous picture)

Apologies Johng and Dazaa, you're right; it does come from the vapour canister not the vacuum tank (I'm still finding my way round under the hood). I'm guessing therefore that my mystery hose would have been connected originally to somewhere on the carb or inlet manifold?

 

[Dazaa]

This thread should help vapor canister for a '71 - CorvetteForum - Chevrolet Corvette Forum Discussion

Looks like there should be a T off the PCV line that goes to the canister. All of this was gone from my 71 so can't compare.