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BS34 Float Help
- Thread starter bul_racer
- Start date
Some of us might get carried away. Why not use aircraft parts and supplies on our beloved XS650! (A statement rather than question) I still maintain it's cheaper than golf or hanging out at the bar.
You are right it's not cheap. I buy it in the 2oz container. A small tub lasts me for 2 or 3 years. I also use it on foot peg rubbers, air box rubbers, ect. Excellent For carb boots and the gasket for them. Water does not wash it off.
Too true. We picked up a lot of stuff along the way...eh?
I use this stuff anywhere I need an anti-seize. A half pint can has lasted 20+ yrs and it's still over half full. No way I'd buy it myself though...
At one time I had two cases of Military surplus low temp grease in lead squeeze tubes. (remember THOSE?)
I've never tasted it. I doubt if a little bit would hurt you. I first used it in a food processing plant. Along with using it on rubber seals for vacuum packaging machines we also used it on motor shafts when going in C-face gear boxes. Worked better than Permatex anti-seize. With wash downs every night it was great because of how it resists being washed off by chemicals and water.
Never knew what it cost then. Carried a tube in my tool pouch. Whenever I used half or so would through it away and get a new tube from parts. Wish I had taken home a few of the half used tubes. LOL
bul_racer
XS650 Addict
I finally got all my carb parts and put it all together. Damn, those little balls and springs for the choke rod nearly drove me off the deep end. Found an earlier thread about getting them from zerk (grease) fittings. By the time I got both balls & springs in I'd lost 6 of the little balls. Some simply disappeared right in front of my eyes and 1 shot across my garage and I heard it hit somewhere probably about 15 feet away. I found that if I know exactly where the ball is I can see it. If not, I'll probably never find it.
I set float levels to 26mm, then did the bench test and both carbs level settled at or right below the spot where the gasket sits, which seems to be right. However, when I mounted the carbs on the bike gas started coming out of the right carb. Not right away, but maybe a minute or 2 later. I pulled the carbs back off the bike and did another bench test. This time it maybe took 3 minutes but then gas started coming out of the right carb.
I checked to see if maybe the float could be hanging up and it seems fine. Float is fine with no leaks. Then I set it up like doing the bench test but with the right float bowl off. Then I pushed lightly to close the needle as I poured gas into the carb to make sure there's no leak when the float is up. No leak.
So, any ideas? Only thing I can think of is that maybe I picked up the wrong float needle when putting it together but I think even that wouldn't explain why it would sit at the proper level for a while and then flood.
I set float levels to 26mm, then did the bench test and both carbs level settled at or right below the spot where the gasket sits, which seems to be right. However, when I mounted the carbs on the bike gas started coming out of the right carb. Not right away, but maybe a minute or 2 later. I pulled the carbs back off the bike and did another bench test. This time it maybe took 3 minutes but then gas started coming out of the right carb.
I checked to see if maybe the float could be hanging up and it seems fine. Float is fine with no leaks. Then I set it up like doing the bench test but with the right float bowl off. Then I pushed lightly to close the needle as I poured gas into the carb to make sure there's no leak when the float is up. No leak.
So, any ideas? Only thing I can think of is that maybe I picked up the wrong float needle when putting it together but I think even that wouldn't explain why it would sit at the proper level for a while and then flood.
Did you remove the float valve body and replace the O-ring? Gotta do that.
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bul_racer
XS650 Addict
Yes, replaced all rubber parts.
bul_racer
XS650 Addict
I did polish the seat. Yes, I thought maybe the float needle rubber tip might be bad but I could not see any damage viewing with a magnifying glass.
bul_racer
XS650 Addict
Looked through my stash of float needles and found one that looks a little more like the one I have in the left carb, put it in and did the bench test. Voila! Stays at the same level. So, I must have put in the wrong one before.
Ready to put the carbs back on but I have some questions about the petcock & the gas tank rubber gasket.
My understanding is that gas only comes out in the 'On' & 'Res' positions if the motor is running but it will flow freely in 'Pri.' In order for fuel to flow in 'On' & 'Res' positions a vacuum must be created by connecting the smaller petcock spigot to the spigot on the intake manifold rubber boot via a hose.
It seems odd to me that the smaller (Vacuum?) spigot on my petcock is pointed towards the rear. Since it should be attached to the manifold spigot it would make more sense to be pointed towards the front??? In other words, pointed away from the main spigot. Is this correctly assembled?
Also, after many years of sitting out in the weather the gas cap rubber gasket was deteriorated beyond recognition so I ordered one from Mike's and installed it. It has not felt right, though I could close the gas cap and it didn't leak but it required more pressure to close than I believe it should and now after never actually being on the bike while running, but only my occasional opening and closing while cleaning out rust it looks like this:
Did I install an incorrect gasket or did I install it incorrectly?
Ready to put the carbs back on but I have some questions about the petcock & the gas tank rubber gasket.
My understanding is that gas only comes out in the 'On' & 'Res' positions if the motor is running but it will flow freely in 'Pri.' In order for fuel to flow in 'On' & 'Res' positions a vacuum must be created by connecting the smaller petcock spigot to the spigot on the intake manifold rubber boot via a hose.
It seems odd to me that the smaller (Vacuum?) spigot on my petcock is pointed towards the rear. Since it should be attached to the manifold spigot it would make more sense to be pointed towards the front??? In other words, pointed away from the main spigot. Is this correctly assembled?
Also, after many years of sitting out in the weather the gas cap rubber gasket was deteriorated beyond recognition so I ordered one from Mike's and installed it. It has not felt right, though I could close the gas cap and it didn't leak but it required more pressure to close than I believe it should and now after never actually being on the bike while running, but only my occasional opening and closing while cleaning out rust it looks like this:
Did I install an incorrect gasket or did I install it incorrectly?
Yes, I think your petcock is assembled wrong. That plate on the rear should be flipped around so the vac nipple points forward. That thick plastic spacer may need to be flipped around with it. Notice the half moon shaped vent channel by the lower left screw. That may need to point forward too, but I'm not 100% sure on that. Maybe someone else can comment on it.
I think you installed the gas cap gasket wrong. I'm pretty sure that lip that's now falling apart is supposed to be tucked under the plate with the 3 screws in it.
I think you installed the gas cap gasket wrong. I'm pretty sure that lip that's now falling apart is supposed to be tucked under the plate with the 3 screws in it.
lots of petcock rebuild info here
https://www.xs650.com/threads/rebuilding-yamaha-vacuum-operated-fuel-valves-petcocks.20662/
I stay away from aftermarket 4 hole valves (the rubber disk) cringe a bit, and order from a Yamaha dealer. Those aftermarket tend to not be the correct thickness, (thin)
Also the length of the shaft with the oring that makes the vacuum seal is critical. Aftermarket and even 40 year old stock tend to end up a bit short preventing the o-ring from doing it's job. A correctly functioning vacuum petcock is possible but takes some effort to achieve.
Yeah the cap seal looks installed upside down. I like to apply syl-glide or such to the seal, wait a bit (warm is good) before stretching it over the steel.
https://www.xs650.com/threads/rebuilding-yamaha-vacuum-operated-fuel-valves-petcocks.20662/
I stay away from aftermarket 4 hole valves (the rubber disk) cringe a bit, and order from a Yamaha dealer. Those aftermarket tend to not be the correct thickness, (thin)
Also the length of the shaft with the oring that makes the vacuum seal is critical. Aftermarket and even 40 year old stock tend to end up a bit short preventing the o-ring from doing it's job. A correctly functioning vacuum petcock is possible but takes some effort to achieve.
Yeah the cap seal looks installed upside down. I like to apply syl-glide or such to the seal, wait a bit (warm is good) before stretching it over the steel.
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The half moon (cavity drain) is correct. It's keyed so it will only fit the one way. The vacuum barb plate isn't keyed and will rotate to all 4 sides. For yours it needs to face forward. Not sure if that petcock is from a different model that needs to face that way or someone's been into it.
The diaphragm holds up pretty good, but there's an o-ring on it that get's hard and flattened over time.... causing it to not seal when the engine's off.
Here's a good replacement. Comment #31.
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