Float Question

[Guest]

Hello,
I have a quick question about adjusting the float levels on my '80 GS 550L
I'm not entirely sure how to properly measure the levels so I was hoping for some clarification so I do it right.
I know the setting is supposed to be 22.4mm (+/- 1.0) and I'm measuring from the spot on the float outlined in the PDF by Mr. Steve and Mr. bwringer. The question I have is that when I tip the carb upside down, and the float settles on the needle valve, it depresses it a little bit. If I measure from this point, all my carbs are WAY off, but from what I read in the Haynes Manual, it sounds like I'm supposed to check it from the point where the float tab just barely contacts the needle. In this case I'm pretty close, I just hold the float with my finger and lower it till it just contacts the tip of the needle.
I know there's some leeway, but I'd obviously want to do it right. (because I know that's the mantra here "Do it right the first time"

Any suggestions? Thanks!

[Thelen82gs550l]

I always made it so the float is level with the case. havent had any problems

[Nessism]

Set the float level by holding the float up so it doesn't compress the float needle spring. It takes keen sight to get it right but take your time and you will get it.

Good luck.

[cp___32]

Thanks. Ok so I set them to they way you describe Ed. When I flip the carbs over so they're sitting the way they would on the bike, I noticed that three of the four needles fall down and setting so they're resting on the float tab. When the float is pushed up, it pushes the needle back into the orifice. The fourth one, the needle doesn't drop under gravity like the other ones. Coincidentally I'm not getting fuel into that float bowl. Did I just find part of my problem? Should all the needles move freely?

[MrZig]

Sounds like you found your problem. Take the float pin out gently as the posts are prone to breaking if you're harsh, then unscrew the tab holding the needle valve on and take it out. I bet you it's all gummed up.

[chef1366]

I've always measured with gravity pushing down on the float. I didn't know there was another way.

[Nessism]

I've always measured with gravity pushing down on the float. I didn't know there was another way.

The springs sag on old float needles, so you need to either replace the needle or hold them up.

[cp___32]

Yeah There's a 1.64mm difference between where the float just starts to contact the needle and where it sits under gravity.
Well hopefully this fixes my fuel flow issues. I was either getting no fuel or very little.
I didn't realize till after putting the carbs back on the bike that I was supposed to check the floats after rebuilding the carbs.

Thanks everyone for your continued help in getting my first bike running!

[Nessism]

Yeah There's a 1.64mm difference between where the float just starts to contact the needle and where it sits under gravity.
Well hopefully this fixes my fuel flow issues. I was either getting no fuel or very little.
I didn't realize till after putting the carbs back on the bike that I was supposed to check the floats after rebuilding the carbs.

Thanks everyone for your continued help in getting my first bike running!

Make sure that one float needle is moving freely too. It needs to be able to slide up and down freely.

[Steve]

If you find that your needle springs are a bit 'saggy', rotate the carb about 45 degrees or so, so the float hinge is higher.
Now the floats won't rest so heavily on the springs. If they still sag too much, rotate a bit more until they don't.

.

[cp___32]

Ok so here's the update. Before starting this thread, I had the bike running on cylinders 3 & 4, while 1 & 2 were getting no fuel into the cylinder. After the float adjust, all four carbs are getting fuel flow through the float bowls, but now cylinders 1 & 2 are firing, while 3 & 4 are not getting fuel beyond the float bowls. I took the carbs off, cleaned the two misbehaving carbs, re-adjusted the floats closer to the positions they had when they were working, but still no fuel flow through them.

I've looked online for the general case, but can anyone tell me how THESE carbs actually work? I can't seem to figure out why fuel gets into the float bowls and then stops. What would be the next step for the fuel in a working carb?

[chef1366]

They use vacuum to pull the fuel from the bowls.
You need four things
Venting of the bowls and tank
good compression
the float valves to flow fuel
the air jets and ports to be free of debris (the two jets on the filter side of the carbs)