cb750 floats stuck

[milenine]

I have had stuck floats on carb 2 and 4 lately--nothing that cant be solved by a little laziness. Instead of pulling the carbs off and working them over good, I just unscrewed the drain plugs and blasted a ton of carb cleaner in and let it run out the overflow tubes for a good 10-mississippi. Then I dumped a bunch of seafoam in the tank. Instant results. Both floats are now working well, no more leaks, and my bike is running stronger than I have ever experienced.

[Lucky 1]

Did you know that carb cleaner has trichlorethylene in it and it can make rubber seals swell up ?

Way up.

[milenine]

Didn't know that. Is that why it is running so good, because the seals are now tighter? It really seems like a different bike, since I did this... Not sure if it is mainly the carb cleaner maneuver, or the seafoam.

[robs750]

milenine wrote

Is that why it is running so good, because the seals are now tighter?

Probly because the floats are not stuck!

[Lucky 1]

The carb cleaner worked but I just feel that it was risky on several levels.

If your carbs have clips on the bowls you can remove the bowl
and remove jets and floats if you are careful to clean them.

I still feel that is better to just remove the carbs.

What made you think the floats were sticking?
Was fuel coming out of the overflow tubes???

[milenine]

Yeah. Carb #2 was pouring gas out the overflow tube and even into the air box. Does that sound like floats? Or maybe the needle was messed up? Help me understand what can go wrong with the carb cleaner. If rubber swells what will happen? I'll be super temped to do this again if I have similar problems and I am short on time. Thanks!

[shinyribs]

Dude,you got so lucky that trick worked! Carb cleaner makes rubber stuff swell cause it is actually sort of dissolving it. The swelling wont hurt anything (like you said, it makes the seal tighter actually) but the rubber can become too soft afterwards and start crumbling. You carbs were not exposed to it for a super long period of time,so i wouldnt let it worry you too much. Worst that can happen is your bowl gaskets or the o-rings on the tee fittings can start to leak. Both are super easy and cheap to fix with the carbs still on the bike. No big deal really except carb bowl gaskets run about $15-20 for set + shipping.

The only real problem with what you did is that it could have flushed the dirt out of the needle seat into an internal passage causing to HAVE to pull the carbs and deep clean them. Also,if your bike has plastic floats (some are brass) the carb cleaner can dissolve some of them in a matter of seconds depending on what material they are made of.

But oh well, it's running good now so: problem fixed!