Hoses connected to air box


Information and questions on GL1100 Goldwings (1980-1983)
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radfordgoldwingresto
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Location: Radford, VA
Motorcycle: 1983GL1100 Goldwing Interstate

Hoses connected to air box

Post by radfordgoldwingresto » Tue Sep 10, 2019 11:19 am



My manual doesn't go in depth as I'd hoped. I am working on an 83 GL1100. There are two clear (albeit old and stained) plastic hoses that go from the air box. One travels through the frame to a mysterious black, sealed cylinder by the back wheel. The other goes back to a connection on the block. Can anyone illuminate me on what these are for?..and If they can be removed (am want to run without the air box).



Good Hondog
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Motorcycle: 1980 GL1100 Interstate

Re: Hoses connected to air box

Post by Good Hondog » Tue Sep 10, 2019 11:43 am

Those hoses are the crankcase ventilation system. The hose with that black cylinder is the outlet side. That black plastic cylinder fills up with oil vapour and requires emptying once in a while (once a year?). The other one leads from the crankcase up to the air box and is the intake side of the system. All those hoses were clear plastic when our bikes were new. Probably not a good idea to modify any of that.

radfordgoldwingresto
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Motorcycle: 1983GL1100 Goldwing Interstate

Re: Hoses connected to air box

Post by radfordgoldwingresto » Tue Sep 10, 2019 4:11 pm

Thanks Hondog: I'm getting new lines but will return it to original set up.

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Re: Hoses connected to air box

Post by WingAdmin » Wed Sep 11, 2019 8:31 am

When the engine is running, particularly when under heavy load (hard acceleration), you get blow-by - combustion gases that make their way past the piston rings and into the crankcase.

This would pressurize the crankcase and blow out seals, so they have a crankcase ventilation system to let these gases escape.

Venting raw combustion products is not good for the environment, so these gases are routed up to the air box, where they are sucked back through the intake system and re-burned.

Because they have come through the crankcase, they are intermixed with oil mist, this gets chucked up that hose into the air box as well.

One of the byproducts of combustion is water vapor. This water vapor can condense in the hose or in the air box. Both the condensed water and oil mist combine into a nasty, congealed emulsion. This has to go somewhere (not into the engine!) so it is drained through the second hose into the black storage canister.

That's why the manual recommends you empty this canister on a regular basis - or more often if riding at high speed (high power) or rain (high moisture) - because it will fill up faster in those conditions.

radfordgoldwingresto
Posts: 10
Joined: Sat Aug 17, 2019 9:56 pm
Location: Radford, VA
Motorcycle: 1983GL1100 Goldwing Interstate

Re: Hoses connected to air box

Post by radfordgoldwingresto » Thu Sep 12, 2019 6:02 am

That's great info. Now that I know the environmental impact and the performance implications, I will not mess with the set up for sure.



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