Air / Fuel leak on #1 carb

Hi all,

Been loving my XJ700N, learning more every day...

I noticed that the metal clamp ring that secures the large rubber air intake hose (what are those called?) to the #1 carb has slipped out of place. I tried loosening the screw, repositioning the clamp ring and re-tightening it but it slipped off again. As you can see in the pics there is fuel leakage which has made the area a little slippery.

I'm wondering if cleaning the area and re-clamping might work or if the rubber will need to be replaced because it may be deformed? Not sure how long the rubber has been in this position as the bike is new to me.

The bike is running decently but I suspect fixing this will improve things. Still wrapping my brain around the mechanics, wondering if this would cause the mixture to be too rich or lean? And does this affect vacuum?

Suggestions and info appreciated!

Cheers,

Timekeeper

 

There shouldn't be any fuel there to leak. Your carburetor is overfilling. You'll need to fix that.

Sometimes the rubber shrinks to where it doesn't want to stay in place any more. Hard to tell from those pictures but I don't see that they look like they've shrunk. Do they stay in place without the clamp?

Clamp needs to just be snug, if you over do it it can walk off the end. Never going to work right wet though.

 

I agree with MiCarl. Fuel is not leaking. It is overflowing. Chances are that cylinder is not even working since the carb is flooded. Check your airbox for fuel being spilled there as well.

You should attach a clear hose to the carb drain and check the fuel level in the bowl.

There are copious amounts of info here on how to check the fuel level in the bowl and adjust it.

 

It would also be prudent to check the oil for signs of gasoline contamination. Quite often a carb with a float issue can be dumping fuel into the motor without you knowing it.

Pop the oil filler plug, stick your nose in and have a whiff. It should only smell like toasty oil. If it smells of gasoline then you need an oil change BEFORE you run the motor any more.

And you need to get the float issue fixed or it will continue to cause problems.

 

Agree on the gas-in-the-oil. It happened to me before I reconditioned my carbs. One of the floats was stuck and spilled gasoline into the engine and airbox.

 

Your fuel tap also needs attention. (assuming this leak occurs with motor not running?)

 

Ok, I have a clear path of action, thanks all.

I was told by the previous owner that the bike had been stored leaned over on the left side for a while, I am wondering if this could be the source of some of the wetness. The bike was dropped on the left side at some point (bent clutch lever and scuffing on the crankshaft cover), I speculate since the damage is so minimal maybe it fell in the garage and didn't get picked up for a while.

I'm studying the valve clearance check and float adjustment processes, looking foward to getting this baby dialed in. Changing the oil again tomorrow, I can't say it smells odd but with fresh oil I'll have a point of reference for the smell check. I cleaned the rubber and clamp ring thouroughly and it has not slipped.

If I am understanding correctly it is necessary to check valve clearance before dialing in the carbs, and it will be necessary to remove the carbs from the bike to set the float levels? Also is the fuel tap the same thing as the petcock?

 

If the bike has been sitting for any length of time. You can count on the carbs needing to have a good cleaning, and possibly a rebuild on the petcock.

If you want a reference for used oil smell. Pull the dipstick on your car, and take a sniff. No reason to waste the money puting fresh oil in only to have the carbs fill it with gas again.

Yes. The valve clearances need to be set properly before trying to sync the carbs. The valves will affect the vacuum signal, and give a false reading if they are out of adjustment.

Ghost