Cb360 engine troubleshoot. Need help

The top of the float bowl area is pretty chunked up on the cylinder thats giving me problems. Could this be the problem? Does anyone know how this could have even happened?

189293_10151187110718118_25574751_n.jpg
 
That's from corrosion, water and carb cleaner over the years. (or maybe relatively recent, I hate cheap carb dip, screws stuff up) The ONLY carb dip worth having is marketed by Yamaha (and even that causes some corrosion if left long enough)
I've seen MUCH worse that work fine though (several people here have sent me carbs to modify for K&N filters)
Is the 'O' ring on shut off valve damaged?
If it fired in exhaust it's probably blowing fuel straight through motor
 
Okay thanks crazypj. Good to know the carb body isnt trash. The fuel shut-off seals are fine. The float was getting stuck before so thats probably why the fuel is leaking again. Im going to have to take the carbs off and check the floats again. Apparently i didnt fix it well enough. Not sure i'll be able to get to this for a few days. Im wondering if the shutoff problem is causing the plug to get fouled. Thoughts?
 
Set float level to 20mm with stock airbox, 21mm with K&N
Search for float levels, I posted pics of correct angle to hold carbs for checking (maybe in 1-800?)
Pics are not in this link but there is a link to photobucket where there are a lot of carb pics including the ones with carb at angle
http://www.dotheton.com/forum/index.php?topic=28876.0
 
While inspecting my ignition system i noticed the end of the right spark plug wire spins freely. Is this abnormal? Could this be causing a bad connection? The other side doesnt spin freely like this.

http://www.youtube.com/watch?v=dwS8UkZF4Rs
 
thrillseeker said:
The top of the float bowl area is pretty chunked up on the cylinder thats giving me problems. Could this be the problem? Does anyone know how this could have even happened?

189293_10151187110718118_25574751_n.jpg

carb mites
 
thrillseeker said:
While inspecting my ignition system i noticed the end of the right spark plug wire spins freely. Is this abnormal? Could this be causing a bad connection? The other side doesnt spin freely like this.

http://www.youtube.com/watch?v=dwS8UkZF4Rs

take the wire out, cut off 1/2" with a razor, screw the plug back on until it's tight
 
Roc City Cafe said:
take the wire out, cut off 1/2" with a razor, screw the plug back on until it's tight

Thanks. Got that taken care of. It's too late to start up the bike now so I'll see if that helped tomorrow
 
Well, i think i fixed it (again). I decided to take the float bowls off before the carbs to see how much gas was in each and this is what i found...

The carb that was having problems was way low on fuel. Eurika! Apparently when i measured the floats, i didnt measure all 4 and they werent all even. So i had to bend the metal brackets to make each float even. Measured all 4 floats to 20mm (swapped floats as well so i could see if one was having problems). Re-installed and all is well, for now.

This doesnt explain why the bike fired up and ran strong after i swapped plugs a few days ago though.
 

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I've read a lot about people setting their mixture screws at 1 turn out and adjusting from there. My screws have plastic on them with a bump that stops it from turning more than a full turn. Do you guys take these off? Should I take mine off to allow for more adjustment? I have to have mine all the way out for maximum rpm when setting idle.
 
thrillseeker said:
I've read a lot about people setting their mixture screws at 1 turn out and adjusting from there. My screws have plastic on them with a bump that stops it from turning more than a full turn. Do you guys take these off? Should I take mine off to allow for more adjustment? I have to have mine all the way out for maximum rpm when setting idle.

It pulls off real easy or you can pry it off with a small screwdriver
 
I think I'm going to need to get new floats. The left side isn't firing now since I swapped the floats to the opposite carbs. It ran for a little while but now it's not. Are these floats made of foam? Maybe it's getting saturated after sitting in the fuel for a while. That would explain why it fires up after working on it and then power gets separating and then quits.
 
I would check by sitting it in a cup of fuel.
I've done a lot of 360 carbs without any issues.
You did have the tang barely touching shut off valve tip when you measured?
 
I'll try that. I did notice the spring in the plug did seem worn out because that float didnt bounce as much as the other. I'll try setting them in a cup of fuel and if that isnt the problem i'll double check the heights as well as swap just the plug to see if thats the culprate.
 
Oh, fit the clamps the other way up and closer to the mounting bracket, the rubber can distort where you have them.
They will be about 10 degrees off vertical
 
Oh, the clamps holding the carbs to the motor. I thought you were talking about the floats still. Haha. Thanks for the tip
 
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