1995 K 1100 RSA vents on fuel tank

[wardie]

I have a question about the evnt tubes on my fuel tank on a 1995 K 1100 RSA.


The front tube is a vent that goes to a one way check valve then into the crankcase . The other one is a simple vent from tank to open hose down by foot peg.


When I lift the tank and remove the front hose there's a large amount of air/vacuum venting from the hose like a pressure build up. I don't know if the tank vent is clogged or just what. Some friends suggested capping front tube and capping the crankcase hose . Just use the second tank vent that runs to hoe to below my foot peg.


Can anyone tell me what they've done or what they suggest as it regards capping the font tube if any pressure problems would entail?

[Filmcamera]

If it is the tube I am thinking of it was a mod done for the CA market, something to do with emissions I think .  I had it on mine and just capped it off with no ill effects.

[wardie]

film camera yes that is where it ends up but I was told to put a cap on the Fuel Tank Front Tube then plug the hose where it attaches to the tank. What do you think?

[Filmcamera]

Well in my case I got the bike with the tube already loose as shown in the photo. It was not attached to the tank at all nor did I have the valve etc that is supposed to be part of the set up.


 I just cut the tube and plugged it at the other end near the engine.

[wardie]

Filmcamera the hose to the engine cover is blocked. I followed the hose from the tank to a check valve then the hose ends down by the footpeg. Crazy thing I had to lift the tank to check some stuff and the hose with the check valve popped off and the tank was doing the purging?  I checked the one way valve and it works as it should not allowing air back into tank but allowing air to escape from the tank. I cannot figue out why their is air purging from the from pipe?

[Laitch]

the hose to the engine cover is blocked.

It would have helped to mention that in your first post just to conserve thinking energy for the rest of us. :giggles You've seen the average age of members here, haven't you? Brain energy conservation is of dire importance.

If I run my bike's engine until the bike's tank is low on fuel, it will burp when its cap is opened. The K75 has two ports at the rear underside of the tank—one to drain moisture accumulating around the fuel cap and one to vent the tank. The front port is usually capped; the crankcase port is capped, too, as Filmcamera described.

Does the K1100 tank have two ports at the rear?

[wardie]

yes it does

[Laitch]

yes it does

The forward one of the pair vents the tank. The rear one drains water from around the fuel cap.

[wardie]

I'm sorry guys I'm just not making myself clear. I know what the vent and drain pipes do what I don't understand is why when the front hose popped off the gas tank it vented for about 5 seconds. Theres a check valve that allows the tank to vent. Maybe I ought to run that hose minus the check valve. There should be zero pressure venting if that valve is working correctly. That's why I'm asking why is it doing that...a long purge like air escaping for a couple seconds until its dissapated.?

[Laitch]

I think you did a good job describing the condition. I didn't do as well in my response.

If it happened to my bike, I wouldn't care why it was doing it. I'd cap off both front ports as others have done to see if it would do it again. The tank vents from one of the rear ports and, as was mentioned, if you run the tank low, it will burp when it is given the chance. Check that the rear vent is clear.

[wardie]

I just thought of something. I only poured about a gallon of gas in the tank. after re-reading the posts maybe this is causing the purging?


I appreciate all the responses this website and members have been a great help to all.

[Laitch]

I just thought of something. I only poured about a gallon of gas in the tank. after re-reading the posts maybe this is causing the purging?

Likely. Fill 'er up. You can always siphon some later for the lawnmower.