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Airbox Vent Line


moto fugazzi

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I'm in the middle of putting my airbox back on (pod filters were on previously), and I have a vent line at the front of the airbox which I believe is for an oil vent line?

Anybody know where the ends of those hoses go, or should I just cap it off?

TIA

Ken

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That line should run to the banjo fitting on the frame in front of the gas tank, behind the triple clamps.

 

That was my first (and only) thought. I currently have the tank on, and the nipple capped off, as I wanted to do a test ride.

I suppose I should install the line. Any benefits to re-connecting it or leaving it capped off? Is it necessary? Reason I ask is that I'm taking it to the dyno shop to have the PCIII properly mapped.

Ken

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It is the vacuum supply to your crank case ventilation. On a big twin, the crankcase ventilation should be intact. The spine frame uses the spine frame, itself, and the intake vacuum to evacuate crankcase pressure:

 

A dedicated rubber hose evacuates the vent from the top rear of the crank case to the front underside of the spine frame (behind the head tube), a "banjo" bolt in front of the tank (on top of the spine behind the headtube) provides vacuum from the airbox, and the fluid portion drains down through the box spine and a braided line back into the back bottom of the sump.

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my vent line is missing also,could that cause a positive pressure in the bypass hose exiting the top rear of the crankcase contributing to oil running out the bottom of my bell housing as explained by Guzzi Moto in the "v11 gearbox leak" thread ?

update;

forgive me I've mistaken the rain water drains on the intake snorkles for the blowby connection, that is connected correctly.I'm searching for a simple solution to my bell housing oil leak.I hope I've found it by simpley titening the hose clamp on the blowby hose above the flywheel.What an odd location to route a leak prone oil hose, I miss took it to be a blown shaft seal.

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Thanks for all of the help!

I installed the airbox and plumbed in the oil line. For once, the bike actually started on the first try! Getting rid of the pod filters seems to be the best mod I have done so far.

I'm off to get a new map for the PCIII on Wednesday, and the bike should run even better! So far, it pulls cleanly from 2k on up. I had Todd at Guzzitech reflash the ECU (timing mods), and couldn't be happier so far.

Ken

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my vent line is missing also,could that cause a positive pressure in the bypass hose exiting the top rear of the crankcase contributing to oil running out the bottom of my bell housing as explained by Guzzi Moto in the "v11 gearbox leak" thread ?

If the vent line between the fitting on the top of the frame and the air box is missing then it would not create a positive pressure in your crank cases but it would create an air leak allowing unfiltered air into your air box. It would also let dirt into your crank cases and contaminate your oil. If the line is missing and both ends are capped off (or just the fitting on the frame is capped off) then it would create positive pressure in your crank cases and could/would cause an oil leak. So please clarify, what do you mean by "missing".

You may want to post this in your original thread.

If the vent line from the back of the motor to the underside of the frame behind the steering head is missing or not on securely then that will cause an external oil leak that can appear to be coming from the rear main seal and it can get oil on your clutch.

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