Carb cleaning/rebuild: leaking float valves: are seats replaceable?

[gtem]

Hi all,

I'm working on bringing my newly purchased '00 Voyager up to snuff. When I bought it it idled on 3cyls with an occasional pop from the fourth when revved. I know it had been stored with ethanol pump gas so I figured I'd pop the carbs off to clean out some gunky bowls/pilot jets/etc. After cleaning, I checked float heights, all were near 15mm and I initially reassembled as such and did a bench leakdown test. I saw some wetness at the air jets so off came the bowls again for a look at the float valves. I also noted that since the floats were set to 15mm not the recommended 17mm, I set them as such. I checked the "wet" float level with a bit of tubing on the bowl drains, all of the fuel levels seem to set roughly 1mm below the gasket surface. I cleaned the float valve seats with a light polishing with a Q-tip with some Blue Magic chrome polish, they seem fine(?). The viton tips of the float needles likewise seem to be pliable and undamaged. The issue is I'm still getting some wetness at the air jets. Not leaking at all, but I can see gas looking down the orifice of the air jets on cylinders #1 and #2, #4 and #4 seem dry.

My question: Are the valve "needles" truly the only thing that can be replaced? I'm used to buying a whole float valve assembly: seat and needle together. Anything else I should check out? Thanks all!

[Nails]

Search on our particular Keihin carbs. (I’m on the road ... and just my phone.) Parts generally widely available.

[triton28]

The seats for the float valves are pressed in place and as such are not replaceable- can only be polished.

[gtem]

The seats for the float valves are pressed in place and as such are not replaceable- can only be polished.

Yeah that's what I had figured looking at the parts diagrams. Now, the logical next step may be to just bite the bullet and buy 4 new OEM float needles ($45 a pop!) but I'm just wondering what else I possibly could have missed that would cause seeing a bit of fuel in the air jets. The viton tips of the float needles look/feel great, could it be the spring loaded tip at the other end that contacts the float tang, if the spring tension in those gets weaker... would that cause the needles to not seat as firmly?

[Nails]

https://dealer.klsupply.com//images/kei ... it_App.pdf says ZG1200A/B Voyager XII calls for Keihin p/n 18-8953x

https://www.amazon.com/Supply-Float-Nee ... B001KO2MMY $37.70/6-pack

https://www.ebay.com/p/171222917 $10/ea

https://power-barn.com/keihin-float-nee ... rburetors/ provides dimensions.

I didn't look very hard, and there might be better deals elsewhere.


You might hang some fuel to gravity-feed the carb rail. If the overflow isn't spilling fuel, I don't think the float valve is leaking. I'm not sure what some wetness in the bottom of the air well really means, but I'm guessing not very much.

[gtem]

Thanks Nails! I ended up finding some for about $9/piece with free shipping on a site called "Murph's Kits" a Concours 1000/older Kaw specialist site. Seller confirmed that the parts are from the same supplier as Kawasaki uses for their OEM parts. Man, talk about a grift by Kawasaki! I did cross-reference the parts and found that Suzuki will sell you that very same float needle for a much more reasonable $16 a piece (apples to apples looking on partshark.com). I'm *VERY* leery of using non-OEM parts for something as exacting as carburetor jets/floats/etc.

Fingers crossed the new float needles solve my problems. Now onto the 2 year old AGM battery that I apparently killed for good after leaving the ignition on "ACC" for the better part of a week

[Nails]

The battery will surely be toast if you try to charge it with a non-AGM charger.

[GrandpaDenny]

You're thinking of Lithium batteries, Nails. AGMs use regular chargers.

[Nails]

No they don’t. Ask me how I know.

[GrandpaDenny]

No they don’t. Ask me how I know.

I'm afraid to ask, but I'm also morbidly curious. How do you know?

[Nails]

I killed one that way. My new charger has an AGM mode.

[gtem]

Ok so I've got my new float valve needles in (ordered supposedly OE-supplier replacements through Murphskits.com, they look and measure same as OE), I used the original needle cages per a recommendation I saw on here. I initially left the float levels at 17-18mm, but have now adjusted them up to 20mm (ie lowering the fuel level even more). However, as you can see in the photo, that is the "wet" fuel level check currently, and I'm still seeing signs of some fuel in my pilot air jets when I shine a light down them. What the heck is going on? It can only be a leak past the new valve needle, a float height issue, or a leak past the pressed in brass float valve seat. Any other ideas or experience appreciated! My next step will be to go back to the old OEM needles with the new raised 20mm float height and see where that gets me.

[triton28]

I harken back to the post from Nails on Monday November 20th as it would seem to me that if the fuel was getting high enough to cause a problem there would be some form of overflow evident. Most likely there would be gas running out of the black plastic overflow tubes onto the ground. This would be coming from the brass overflow standpipe/s in the float chambers.
Perhaps what you are seeing is merely capillary action of the gas up into the orifice you are looking into.
Just a thought.

[Nails]

I seem to recall that the correct float-bowl level is a tad above the float bowl gasket. I don't think you have a good reason to lower this.

[gtem]

I harken back to the post from Nails on Monday November 20th as it would seem to me that if the fuel was getting high enough to cause a problem there would be some form of overflow evident. Most likely there would be gas running out of the black plastic overflow tubes onto the ground. This would be coming from the brass overflow standpipe/s in the float chambers.
Perhaps what you are seeing is merely capillary action of the gas up into the orifice you are looking into.
Just a thought.

Yeah this is honestly what I'm beginning to think as well. Maybe some amount of capillary action is normal? I've rebuilt something like 8 sets of Mikunis (and mikuni style Keihin Cvs) over the last two years doing various projects, and when I used to do my final leak check on the bench, it was simply "is there gas running out of the carbs" or not. I was just scrutinizing these Voyager carbs so much because I don't want to get in a cycle of taking them on and off, I wanted to get them 100% right off the bat. So maybe I've just ended up down a paranoid rabbit hole! If they don't leak anything by the end of the day on the bench, they're going on the bike.

[Nails]

I've said this elsewhere here, but I think a "trick" for CV rebuilds is to polish the piston and bore with aluminum foil. YMMV.

[gtem]

I'm a bit confused, what piston and bore are you referring to? The float valve seat? Or the throttle slide?

[Nails]

The big throttle piston. It just floats in there on a very soft spring. Stiction there is a bad thing.

[gtem]

Just wanted to follow up on this to report that the carbs are back on the bike, I ultimately ended up using my original float valve needles and cages, everything seems fine! Carbs are back on the bike, after discovering and then correcting a bit of an odd synchronization issue, the bike absolutely purrs. Boy, I hope that I don't have to take the carbs back off the bike anytime soon, what a pain! For comparison, I can pull the carbs off my XS1100 in about 7 minutes, and back on the bike again in barely 10. Granted, that's a totally different era/class of bike.

[GrandpaDenny]

Just wanted to follow up on this to report that the carbs are back on the bike, I ultimately ended up using my original float valve needles and cages, everything seems fine! Carbs are back on the bike, after discovering and then correcting a bit of an odd synchronization issue, the bike absolutely purrs. Boy, I hope that I don't have to take the carbs back off the bike anytime soon, what a pain! For comparison, I can pull the carbs off my XS1100 in about 7 minutes, and back on the bike again in barely 10. Granted, that's a totally different era/class of bike.

Take heart in the fact that the more you ride your bike, the less you have to mess with the carbs, especially if you can find ethanol-free gas. It's the sitting around that messes up the carbs. So ride ride ride!

Live, laugh, love, ride, and don't go SPLAT