2010 Qlink XF200 loss of power (fuel tank vacuum) at high rpm, wide open throttle

**lakeclark** · 08-11-2011, 02:45 AM

When I first got my Qlink XF 200, I noticed a loss of power and engine cut-off after operating at high rpm, i.e. wide open, for a few minutes. The engine would restart after momentary rest. I subsequently determined that the engine was suffering from fuel starvation from a vacuum build-up in the fuel tank, i.e. fuel not flowing into the carburetor. My quick fix, was to break the o-ring seal on the fuel filler cap, thus allowing release of vacuum build-up in fuel tank. This is probably a less than ideal fix? I thought I had seen some thread / information about a fuel tank breather tube, but am unable to re-locate the thread.
Can someone help direct me to information on the fuel tank breather / vacuum relief mechanism?
The reason I ask, is, riding down the road this afternoon, the engine cut-out on me at max speed / rpm. It has not done this since I broke the o-ring, about a year ago. I removed the fuel cap, to check fuel level. I also thought (illogically) that the o-ring had resealed? Probably not possible. The engine did immediately re-start and run fine at slightly less than max speed. I am hoping to inspect the fuel breather / vacuum relief mechanism to discount that as source of trouble. (And replace broken o-ring sealing fuel filler cap?)
Thanks in advance, Clark

**barnone** · 08-11-2011, 12:47 PM

The tank is vented through the charcoal canister.Some people remove the charcoal canister, plug that hose, and then start having fuel delivery problems. Not you I hope.
If you still have the charcoal canister, then I guess there is a chance it could be plugged up. Over filling the tank and getting fuel in it can cause that problem as is mentioned in the owner's manual.

**lakeclark** · 08-11-2011, 02:20 PM

Vince. Thx. Where is the charcoal canister located, how recognizable?

**barnone** · 08-11-2011, 04:33 PM

I sold my XF200 so deleted all my photos of it but if you take off the right side cover and you will see it. It's black and has a lot of hoses connected.
I would not remove it but some yahoos remove it and plug the hose to the tank and then bitch about their bikes being a POS because they get a vacuum in their tank.Then they remove the gas cap gasket and complain about a fuel leak at the cap.

**lakeclark** · 08-11-2011, 05:34 PM

I believe I found a pic on the forum of the charcoal canister you refer to. I will investigate this further, later this afternoon. See black canister in 3rd pic of these 3:
http://www.mychinamoto.com/forums/sh...ull=1#post6424

**barnone** · 08-11-2011, 09:23 PM

Clark,
Yep,that's it with all the hoses connected to it.
BTW, I'm in Fort Myers in the winter and WNC in the summer.

**david3921** · 08-13-2011, 07:03 PM

That's my bike. I have since removed everything except the check valve and plugged the various places where the hoses went. The check valve (red arrow in the picture) vents the gas tank. It is all part of the air injection stuff so it all went when I removed that.

If you have this type of set up (some don't), check that the valve is still working. The valve only works one way and there is an arrow on it to show which way the air flows. Air enters where the blue arrow is to vent the gas. If any of the lines have gas in them, the tank won't vent.