Tank vent and overflow routing

[danl]

I'm in the final stages of reassembly after doing a bunch of work on the bike and I can't remember exactly how the vent and overflow hoses from the underside of the gas tank were routed (it's been apart for a while!).  If anyone remembers or happens to have their tank off now could you give me some advice?  It is a 2000 naked.

 

Here is what seems right based on the length and shape of the hoses:

The hose on the left will run along the left side of the spine and down between the transmission and the starter motor.

 

The hose on the right will run down along the top of the spine, under the airbox, between the shock mount, to the right of the shock, then down between the frame and swingarm, behind the gearbox, through one of the hose management loops above the exhaust crossover.

 

Thanks in advance if anyone is able to help out!

  

[AndyH]

Mine has never had these hoses since I got the bike. As far as I can see they'd make tank removal and refitting a whole lot fiddlier.

 

Nevertheless as I've never seen them in place, and they must have been put there for a reason (like the vermiform appendix perhaps?), I too would be interested in the outcome of this thread.

[Steve S]

I only have the left one which is to drain water and spilled fuel from the filler aperture so needs to go down by the starter and to the ground, the right hand one is just for tank venting so not so important to have a hose fitted, if you haven't checked them they are probably blocked up anyway.

[PhilPassmore]

I only have the left one which is to drain water and spilled fuel from the filler aperture so needs to go down by the starter and to the ground, the right hand one is just for tank venting so not so important to have a hose fitted, if you haven't checked them they are probably blocked up anyway.

And if the water drain one IS blocked, please sort it before you get a tank full of water from accumulated rain, rust in the tank, a blocked fuel filter and a trashed fuel pump! Cheap to fix, expensive if overlooked,

[docc]

On the early Sport, the overflow (left) hose routed down the left side, through a one way valve (which must be oriented vertically), behind the starter, and fixed (zip-tied) to the 90˚ angle of the steel braided return line to the sump effectively keeping any overflow off the hot engine. Sure it dumps in front of the rear tire, but it's off the engine.

 

The right side tank vent connected to an elaborate system of emissions plumbing. The "hose management loops" were for the two 1/2" fuel lines originally routed from two carbon canisters in the tool tray with vacuum from the intake taps. Twenty feet of rubber hose and 2 canisters: 5 pounds!

 

The two tank hoses can be "Y-ed" together in front of the airbox which keeps them closer at hand when reaching under there from the front to reattach. Many bikes have had the overflow valve removed as it sometimes contributed to "tank suck."

 

Also, if you choose to remove the "hose management loops,' be advised: the fastener hole is contiguous with the gearbox oil and will spew a perfect stream of gear oil when removed.

[danl]

Thanks for the comments everybody.  I think I will T the lines together and run one single vent / drain down to one of the areas I described earlier.

 

I did read a number of comments in another thread about just leaving the hoses off.  It seems pretty well proven by many accounts that this doesn't result in immediate fiery death, but I still feels a little wrong to leave them off.

 

Yes, my bike originally had all the emissions plumbing but it magically fell off one day and landed in a rubbermaid bin in the garage.

 

Thanks for the tip about the through hole into the Gearbox.  Glad I didn't find that out on my own!

 

Dan

[dangerous]

I only have the left one which is to drain water and spilled fuel from the filler aperture so needs to go down by the starter and to the ground, the right hand one is just for tank venting so not so important to have a hose fitted, if you haven't checked them they are probably blocked up anyway.

LMFAO... bloody Iti's I only had the right one, since added another tho after the drain blocked...

[Camn]

This is how it works on mine, "the European version". I read a good tip how to open a blocked vent hole. Take a wire rope (a thicker if at hand), put it to a drill. Some WD40 or equivalent into the hole and "drill" with the wire. Afterwards keep the route open by blowing with compressed air. The route which takes the water out is normally clogged. These instructions worked for me.
 

[Scud]

I've got the tank off for the first time and am trying to figure out how much hose to dispose. I dropped the emissions canister a few hundred miles ago and it's running fine. In fact, now that I think of it, I have not had a single hiccup since disconnecting it and plugging the vacuum line. It was hiccuping occasionally at idle - even stalled a couple times. (I increased the idle speed a bit at the same time).

 

The line from the left side of the tank disconnected easily and appears to be routed as described (although I did not remove the starter cover to verify the existence of the one-way valve). Clearly, this one stays as-is and gets reconnected.

 

 

 

The hose (stamped with "Made in USA" and something about emissions on it) from the the right side of the tank has the permanent clamps (can't be undone and re-used). After routing through a small plastic thing (which I assume is a valve and part of the California emissions system) this line simply drained by the exhaust (because I cut it from the emissions canister and did not plug it).

 

The vacuum line I plugged from the emissions canister goes to a T-connecter, the other lines from which then attach to fittings on the intake manifolds at the heads (between heads and throttle bodies).

 

 

 

My questions:

 

1) Can I simply run a drain line from the right side connecter? - or is it best to leave it open, or connect with with a T-connecter to the line that come from the left side?

2) Is there a reason (other than to make the emissions system work) that the two manifolds should be connected by a vacuum line?

3) If the answer to 2 is "no", can I remove the whole T-line and put vacuum caps on the two fittings?

4) If 3 is "yes", is there another reason to have these fittings? If no, then should I just install some metal plugs so I never have to think about them again?

 

 

 

Bonus (aka off-topic) question:

 

What adhesive should I use to re-attached the parts of the heat shield that are peeling away?

[czakky]

You do need to have those lines open. One opens to the atmos. to fill the tank back with air as it empties. The other line drains vapor and/or overfill gas. Both important, I just "T'ed" them together into one line for simplicity.

 

You can use any adhesive that will take the heat. I think someone recommends "shoe-goo"...? Not sure, check out Docc's tank off checklist while you are there.

[Scud]

Thanks for the answers to #1 and the "bonus question" - both regarding the tank.

 

I still have a T connecting two intake manifolds and leading back to where the emissions canister used to be - the plugged line in second picture. I am still looking for answers to 2-4. My intuition says to plug the fittings with vacuum caps. Are the fittings in the third picture needed for tuning or some other purpose - or should I just install solid plugs?

[luhbo]

I wouldn't "T" it. These nippels have different functions, one drains the water coming from rain or bike washing, the other one leeds air back to the tank. I wouldn't mix them.

 

for 3: you can plug the fittings. 

 

for 2: over here the fittings are not connected. Anyway, some have them tee'd and connected to the pressure valve on the right side of the tank. Opinions about this vary widely. Naturally, one could say

[Scud]

Thanks. I used the leftover emissions hose for the right side tank vent and ran it behind the starter so it drains next to hose for the left side drain. It's good to know that one is a vent, while the other is a drain. Different functions, so no T to join them.

 

As for the manifold vents, I installed rubber vacuum caps and clamps. I got nervous when it ran really roughly at first - but then I realized it was because of air in the gas line. Runs fine now.

[docc]

Capping the vacuum taps is fine. Although, I would carry a couple extras on board just in case one goes missing. If the cylinders are out of synch, the caps can be damaged from a pop back through the intake.  Once you've got it tuned well, there's no issue.  Those are the vacuum ports for your balancing manometer.

 

I plugged my taps with solid fasteners for a few years, but had them in and out enough to damage the aluminum threads. Ugh - Heli-Coil and back to the rubber caps!

[Scud]

Capping the vacuum taps is fine. Although, I would carry a couple extras on board just in case one goes missing. If the cylinders are out of synch, the caps can be damaged from a pop back through the intake.  Once you've got it tuned well, there's no issue.  Those are the vacuum ports for your balancing manometer.

 

I plugged my taps with solid fasteners for a few years, but had them in and out enough to damage the aluminum threads. Ugh - Heli-Coil and back to the rubber caps!

 

That's the kind of advice that can make the difference between riding home and needing a ride home.  Thanks.