Good sealant for carb float bowls?

[Carter Turk]

Would it be worth trying to double up the gaskets for trial n error purposes?

[Nessism]

If you want to go down the rabbit hole regarding checking fuel level read this post from over on KZ Rider...https://www.kzrider.com/forum/forum-...ing-fuel-level

[KEITH KRAUSE]

I appreciate the reply, but doubling up the gaskets wouldn't work. While it's possible it could effect the leaking one way or another, it would lower the bowl. That would change the relationship between the jets and fuel level. I may be wrong, but with more fuel available in the bowl, I believe it could change how the jets draw fuel and compromise the air/fuel ratio? At the very least the over-flow tube built into the bowl would be lower and fuel would overflow too easily.

[KEITH KRAUSE]

Ed, thanks for sharing that info.
As far as fuel level and my carbs leaking, fuel level isn't the problem. The gaskets, if doing their job, would seal against leaks regardless if the fuel level was at what I would consider an extreme, say, 1/8th inch too high. At 1/8th inch too high, the bike would run so rich it would be un-rideable. My bike runs well, which tells me the fuel levels are at least reasonably accurate.
I won't get into my reasons, but I've always had a habit of turning off my Pingel valve about 15-20 seconds before actually turning the motor off. I place the bike on the center stand, turn off the valve and let it idle those 15-20 seconds and turn the motor off. As far as the usual several days between rides, the bike sits there, level, with lower-than-normal fuel levels.

[Gorminrider]

not TRYING to be an Ahole, but per"

I've always had a habit of turning off my Pingel valve about 15-20 seconds before actually turning the motor off

"but if you want to lower the level further, maybe run the bike until it really dies, including using the choke.

I looked up your fuel level and I gather it's within 3-5mm of the "mating surface of the float bowl, with the engine idling ..." so I can see why the gaskets are a concern where there's a rich level... 5 mm above "the mating surface" seems quite a lot
"...the height is measured 20mm from the rear of the bowl" suggests a tilt taken into account but maybe it's the position of the jets that's the crux, or simply the mechanical properties of the flexible pipe in the gauge.

BUT all that aside, when I look at the pictures in several shop manuals, they always seem to show this...whatever the "allowable" limits(CV carbs..)
fuelLevelCVcarbs.jpg

Obviously the picture they chose to display as an example shows the fuel is well below the seam. The picture in your manual,that I have anyways, I can't see. It's not argument, it's an idea. Your bike might run a little leaner than the "highest allowable level" or you won't notice. I don't know. But it certainly could fix an unfixable gasket problem.

[Gorminrider]

If you want to go down the rabbit hole regarding checking fuel level read this post from over on KZ Rider...https://www.kzrider.com/forum/forum-...ing-fuel-level

Huh! what's unseen revealed! a reminder per specific gravity of Ethanol gas too

E10 glass level 800x600.jpg

[GregT]

I appreciate the reply, but doubling up the gaskets wouldn't work. While it's possible it could effect the leaking one way or another, it would lower the bowl. That would change the relationship between the jets and fuel level. I may be wrong, but with more fuel available in the bowl, I believe it could change how the jets draw fuel and compromise the air/fuel ratio? At the very least the over-flow tube built into the bowl would be lower and fuel would overflow too easily.

It won't change the relationship betwen level and jets. The float valve and pivots are in the body of the carb - not the bowl.
It will slightly increase the volume of fuel in the bowl which will have no effect on running whatsoever.

There is always the possibility you have one or more porous bowls....It does happen. Painting them with an epoxy sealant can cure this.

[Nessism]

Keith,
If you have your heart set on using sealant I've got a few tubes of PPG PS 890 A2 aircraft grade fuel tank sealant I picked up from where I work. We use the stuff in gross and the packages I picked up just expired shelf life, it should be perfectly fine for this application though. This stuff is a catalyzed sealant so after mixing it's junk unless used. It dries rubbery and isn't intended as an adhesive, it's a sealant, so I think you would be able to separate the float bowls without damaging them.

[KEITH KRAUSE]

It won't change the relationship betwen level and jets. The float valve and pivots are in the body of the carb - not the bowl.
It will slightly increase the volume of fuel in the bowl which will have no effect on running whatsoever.

There is always the possibility you have one or more porous bowls....It does happen. Painting them with an epoxy sealant can cure this.

I still think there's a possibility the jets could draw fuel easier. Easier to actually matter? I don't think so. I'm not going to double up gaskets in any case to find out. It would slightly lower the over flow tube and that would make it easier to spill fuel even with a fuel level within specs.

[KEITH KRAUSE]

Keith,
If you have your heart set on using sealant I've got a few tubes of PPG PS 890 A2 aircraft grade fuel tank sealant I picked up from where I work. We use the stuff in gross and the packages I picked up just expired shelf life, it should be perfectly fine for this application though. This stuff is a catalyzed sealant so after mixing it's junk unless used. It dries rubbery and isn't intended as an adhesive, it's a sealant, so I think you would be able to separate the float bowls without damaging them.

Thanks, Ed. Actually, I don't want to use sealant at all. I know the bowls are designed to seal with only gaskets in good condition, but I have to do something. I never try to be cheap and re-use gaskets. I make sure all surfaces are clean, etc. I place the gaskets correctly and uniformly tighten them down. I use hex bolts because the stock Phillips are garbage in my opinion. I follow every "rule" correctly and I get leaks as a result. Looking the carbs over for any leaks that could be confused for bowl leaks, I've inspected the fuel "T" and other fuel tubes, the fuel line, the pilot fuel screw o-rings, and cannot see any sign of trouble. All I can do is try the Z1 gaskets that you say are a bit softer and thicker. It makes sense to try them. As for adding a thin coat of sealant to assist the Z1 gaskets, I'd like to trust that the "different" gaskets will be enough to stop the leaks but I'd like more insurance. I still haven't held the Z1 gaskets in my hands to decide for myself. I may try them without sealant, but I'm leaning towards sealant because I'm sure I can apply it sparingly so that it will help seal without excess sealant squeezing out and into the bowl.
The Permatex Perma Shield sealant 85420 that I've chosen stays flexible and doesn't harden. It doesn't dry so it can be applied slowly and very thin. It remains tacky and allows for multiple assembly/disassembly. It fills minor gaps/irregularities. It allows the bowls to be removed easily. If you take a small piece of it and rub it between your fingers, it dissolves. In gas, it disappears.
I'll most likely try it. If I don't like how it applies, I'll stop and just have to trust the Z1 gaskets are enough.
I contacted Robert Barr and he's sending me some of his "F" o-rings to fit my Z1 fuel tube between carbs 1 and 2. He's doing me a big favor by sending them and I owe him for that. Great guy! The o-rings are only 4 years old from a previous carb service but I don't want to try re-using them. The Z1 gaskets are on the way.
I appreciate the help.

[KEITH KRAUSE]

I finished the carb work. I'm really happy to say the carbs aren't leaking at all.
I decided to not use the gasket sealant. The Z1 bowl gaskets are softer as Ed mentioned. I decided that would be the difference and it was. I didn't try extra tightening on the stainless steel hex bolts. I just tightened them all and the next morning tightened them a tad more, not as much as I've tried the last couple of times I replaced gaskets.
I studied the genuine Suzuki gaskets and I believe the problem is the last two sets I've installed seemed harder than normal. Maybe not, but they almost have a "plastic" feel to them and in my case, couldn't seal well over that thin raised ridge on the carb body. Since these gaskets can sit around a long time before being used, I think they can get harder.
All I know is, the Z1 gaskets were the only change I've made and the leaks are gone.
I appreciate everyone's help!

[KEITH KRAUSE]

I have never seen or heard of a carb body crack due to overtightening of the bowl screws. The thread will strip long before the body cracks.

Turns out you were right. When I got the bowl off I saw what looked like a spring in the hole. The threads just spun out in one piece.
My whole life, every time I've stripped a fastener it happened as I was tightening, not after. I guess the last time I tightened the bolt I was right at that moment of over-tightening it and stopped just before I could actually feel it? Then I went to snug it down later and it immediately stripped. Only thing I could think was the carb body cracked from too much torque.
Either way I was lucky to have a spare body. A nut would've worked as a plan B but would look bad.
Live and learn. Thanks again, Agemax.

[KEITH KRAUSE]

Ed, thanks again for mentioning the Z1 bowl gaskets being softer than the Suzuki's. If not for that, I would've bought some more Suzuki gaskets and slapped on the sealant. I'm glad I didn't have to try that.
Thanks for your advice.

[metalfab]

I swore I had some bowl gasket leakage recently, and it turned out to be the O rings on the fuel transfer tubes. If you absolutely have to kill it the first time, Hylomar gasket sealer. It's expensive but worth it. That said never put sealer on your bowl gaskets.

[OldVet66]

I just caught this thread a little late. I had leakage problems with the Z1 gaskets, so I went back to the OEM gaskets. No sealant but I thoroughly cote both sides of the gaskets with dielectric grease no excess. I have not had leakage problems but the reason I do this is the gaskets always come loose without leaving anything on the carburetor bodies or bowls if you are careful when pealing them off for replacement when rebuilding the carburetors.