1974 CB360 Engine Troubles (I think)

crazypj said:
I've done a load of 360 carbs, 6mm seems a lot to adjust but I have seen tem with very low float levels. Are you set at 19mm or 21mm?
I saw a tutorial online that said to adjust to 16mm, is that too low?
 
irk miller said:
You said the line had no fuel in it when you started, but it was full when you got back? That's normal. The float doesn't open until you start to drain it while running. If you have the lines off, or just installed them, then they'll stay empty until you use some fuel. If no fuel was going into the carb, then the tube would never fill up.

Truth.
 
rsjudka said:
I saw a tutorial online that said to adjust to 16mm, is that too low?

Yes too low. Like PJ said. 19 - 21. I have mine at 19 he likes them at 21mm. Anywhere in there will be a good place to start.
 
irk miller said:
You said the line had no fuel in it when you started, but it was full when you got back?

Well one line filled with fuel and the other was empty when I first opened the pet cock. Then when I came back both had fuel, but the left only had fuel on the carb side, and the right had fuel only on the pet cock side.

Also, when I was riding, it accelerated really slowly. What would cause that?
 
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Sorry I didn't know how to explain it correctly, but from my understanding the fuel on the far line isn't getting into the carb?
 
If the fuel line is touching the engine or close to touching. It could be boiling the fuel inside the line.
Cut lines as short as possible without kinking. And make sure they dont touch anything.

fuel can boil at 90f degrees. Boiling fuel will cause bubbles to form inside the lines.

I have heavy duty black fuel line w insulation sock on mine and heat shield under the tank. To prevent this exact thing.
 
read the previous post. It's weird but completely normal to see air in 360 fuel lines. Trek has thebest idea having heat shielding on lines.
The carbs get very hot when bike is runnng, the main cooling is from fuel evaporating. 16mm float height will cause real rich mixture at all engine speeds.
 
You just need to sort out one problem at a time.

Did you get the new diaphragm installed?

Keep in mind a torn diaphragm will make it go lean in higher rpm.

No fuel in the carb bowl will make it go lean in all rpm. ;)

A lean condition is more damaging (over heating, cracked valves, holed pistons...etc) to the engine than rich condition. So, dont let her run lean.

With the engine cold. Open bowl drain screw and drain carb bowl, leave bowl drain screw open, open fuel tap, float needle should be open and gas will start to pour out of bowl drain, close bowl drain screw. If no fuel comes out after opening fuel tap, you got a stuck float/needle.
 
I've been thinking of fitting a 'Tufnol' plate to the mounting plate to deflect some of the heat away from carbs. I have some about 1/16" thick sheet. The carb mounting plate has the ejection pin bosses that could easily be drilled at tapped 3mm~4mm.
 

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crazypj said:
I've been thinking of fitting a 'Tufnol' plate to the mounting plate to deflect some of the heat away from carbs. I have some about 1/16" thick sheet. The carb mounting plate has the ejection pin bosses that could easily be drilled at tapped 3mm~4mm.

Ive worked plenty on carbs w engine hot enough to burn my knuckles.
But dont recall being overly concerned about the temp of the carb bodies. (at the time)

Next time I go for a ride I will check the temp of the bodies.

I used the gold foil tape to shield the 360 tank w great success.

Now got a scrap of "the good stuff" left over from the BMW tank.

Its self adhesive fiberglass mat w aluminum shielding. It could be cut to fit and adhere directly onto carb mount plate.

Your idea of a separate plastic shield w larger air space between would be best. I had to google "Tufnol" haha.

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Not sure the BM needs the expensive shielding as te flying brick has most of the heat well away from tank. I know it won't arm anything though and may well keep fuel cooler. Any idea if fuel economy is better with it?
 
Back from a well-needed vacation, and I think it's awesome that you guys started having convos about your own bikes here, really interesting stuff!

I just installed my new flasher, and although the stock lights are brighter, the LEDs still aren't working. What are some things I should look at to see what could be the issue? (using aftermarket turning signals w/ pos and neg wires)

BTW, I did try to swap the two wires on the flasher connectors, but that only made the filament bulbs not work
 
What colour wires are coming from aftermarket indicators?
You may have running lights in them and need body grounded?
 
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