Spring flooding!

[tnfazer]

Finally nice & sunny, so I decided to take the bike out for a spin. (We don't have polar bears here, but three weeks ago you could still go skiing).

I had drained the float bowls in the autumn, and when I connected the battery and turned ignition on the fuel pump buzzed quite normally. The bike started ok with choke on, but after a few seconds started running kinda odd, wouldn't keep going except on throttle, and then I noticed I was standing in a fuel puddle.

Here's what I've found out so far:

- Fuel just oozes out of apparently from the front of the carbs, with no clear source of where it comes out.

- Tapping the float bowls didn't seem to help, tried that twice after draining the float bowls. I've had a stuck float once earlier, right after I put the Holeshot kit in, but that was easily rectified by tapping the bowls (thanks Mike!). But that time the excess fuel spewed out of a carb overflow hose.

- If I drain the float bowls and then switch ignition on but don't start the engine, after a while fuel starts to seep out of carbs 3&4 while 1&2 seem to remain dry. I don't know if waiting longer would start the leak also from 1&2.

The bike's got a Holeshot kit in, and at the same time I at least tried to adjust the float levels as per Pat's instructions. Apart from the first problems, it has run fine with the kit for 3,000 miles and one spring start before this.

Any ideas?

(God, how I hate pulling carbs... Any suggestions as to how to get especially the 2&3 airbox side rubber boots to seat easily on carbs are also welcome. Nearly drove me crazy the last time before I got them straightened and clamped.)

[Falcon 269]

If it's not a stuck float chances are it's the float needle seat O-rings:

 http://www.yamahafz1oa.com/forum/showthread.php?t=103599&highlight=found+carb+failure+mode

The key to getting the carbs in and out easily is to make sure the airbox goes back far enough.  You should get about 1cm clearance between the carb and the airbox side rubber boot.  To do this, pull the EXUP cables out from behind the airbox and also look for the zip tie on the crossframe rail.  If the block on this joker is in the wrong place, it will rob you of clearance.

Re the airbox rubbers, here's a tip.  When you slacken the clamps, push them back on the stubs and then re-tighten them.  This prevents them fouling and also helps keep the stubs round.  A squirt of silicon lube or WD40 on re-fitting helps a lot, too - particularly in getting the carbs into the head-side stubs.

[tnfazer]

If it's not a stuck float chances are it's the float needle seat O-rings:

 http://www.yamahafz1oa.com/forum/showthread.php?t=103599&highlight=found+carb+failure+mode

The key to getting the carbs in and out easily is to make sure the airbox goes back far enough.  You should get about 1cm clearance between the carb and the airbox side rubber boot.  To do this, pull the EXUP cables out from behind the airbox and also look for the zip tie on the crossframe rail.  If the block on this joker is in the wrong place, it will rob you of clearance.

Re the airbox rubbers, here's a tip.  When you slacken the clamps, push them back on the stubs and then re-tighten them.  This prevents them fouling and also helps keep the stubs round.  A squirt of silicon lube or WD40 on re-fitting helps a lot, too - particularly in getting the carbs into the head-side stubs.

OK, much appreciated!

I'll try tomorrow knocking the carbs once more, this time with fuel in them. Previous attempts were made on drained carbs, maybe the floating floats are easier to unseat. If that fails, I'll have to pull the carbs, and I'll replace the O-rings anyway while I'm at it. The bike has only 30,000 kms but 10 years on it, so it wouldn't surprise me if some substandard O-ring would have gone bad. 

I wonder what determines where the fuel comes out? As mentioned, the previous time it all just flowed out of carb overflow hoses, but now those are dry and it just oozes out from the carb.

Anyone know any Euro webshops that would sell those 7,5*1,5 mm O-rings?

By the way, is it absolutely necessary to drain the coolant before removing carbs, as the shop manual states?

[Falcon 269]

Not necessary to drain coolant.  When you remove the side covers, set aside two of the bolts.  When you take off the coolant feed pipes to the carbs, just plug the ends with a bolt.

Most likely the fuel level is high enough to cause the leak from the float bowl flange but not high enough to enter the overflow pipe.

While draining the float bowls for winter storage is good for preventing gumming inside the carbs, the downside is that the O-rings and other synthetic rubber seals dry out.  I suspect this is what has caused the float seat O-rings to leak now.

[tnfazer]

Great. "Swamp there, bog here", as a local saying goes. I started draining the floats when a clogged main jet (?) gave me a bad scare 3 winters ago. It started and idled nicely, but when I tried to pull away into the traffic all I got was coughing and sputtering. That time it cleared itself, fortunately.

Do one, and you have to pull the carbs come spring. Do the other, and you still have to pull the carbs come spring  Next winter I may try running the bike warm every 3 weeks. That probably fouls the plugs, for neighbour's sake I can't rev it too much...

Mike, are you with our American co-Fazerists about the relative merits of Vitol vs. Buna-rubber (nitrile) O-rings? More advanced always sounds better to me (that's probably why I ride a bike that's a decade old...) but you can't get alcohol-free gas here at all. 5% ethanol is the minimum, I usually run 10% with no problems, and if that melts Vitol O-rings then it's an easy decision.

Any other rubber parts I should prepare to change while I'm at it (main & pilot jet O-rings, float bowl O-rings, etc.)? Does any have the sizes for other jet O-rings? Float bowl "O-rings" probably have to come from Yamaha at € 10 each. Float needle seat O-rings are not even available individually, you have to buy the entire float needle set at €51 /each!!!      (Parts info from here)

[tnfazer]

Pheww! 

I let the fuel pump fill the carbs,and then tapped on float bowls and that seems to have sorted them. Lesson learned: tapping on empty float bowls only gets you dings on them but not much else.

But the issue of O-rings that Mike brought up remains valid. It's going to come up sooner or later, so I'm going to stock up on those. All ideas on where (and for pilot and main jet O-rings what kind) to get are welcome!

[Falcon 269]

You only need the float seat O-rings - all the others go a lifetime without problems.

I've got nitrile rings in mine but never really gave it any thought.  I think I bought a job lot off ebay for under a fiver, something like that.

[tnfazer]

I'll start searching. Let's see if I have to buy a hundred of them.

In case anyone is interested, Louis in Germany sells complete carb repair kits for Gen 1 Fazer for much less than Yamaha charges for a needle valve assembly:
http://www.louis.eu/_30587400894c99ef5e0c1afb4d9967f4d9/index.php?topic=artnr_gr&artnr_gr=10042430&typ_id=RN06