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Fuel level cb77 float bowl

Fuel System: Gas (Petrol) tanks, Carburators
chrisnoel
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Fuel level cb77 float bowl

Post by chrisnoel » Sun Aug 18, 2013 9:22 pm

Started my CB77 for the second ride and noticed the smoke bellowing out of it was getting worse. My first thoughts were bad rings or bad valve seals. Checked the plugs and found they were getting fuel rich sooty and not oily. Breathed a sigh of relief and then turned the air screws down to one full out rather than two as they were previously set. Turned my attention next to the fuel height in the bowls. I know my valves are working as I have clear lines and I can see the fuel stop flowing when the floats turn them off. The floats were bench set and I know this is crap so I'd like some advice on where the fuel level should be regardless of float height. Removed the bowls and a little fuel dumped out so I knew that they were at least full to the front edge which is lower than the rear edge. I've raised the float tabs somewhat lowering the floats and the bike is still not starving for fuel and the smoke is much better. I plan on rigging up tubes to the drains to adjust them better but I just don't know what level I should be shooting for? Once the float height is good I should be all set as I've done my rounds with mains, pilots, needles and such before.

Goodysnap
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Location: Lansing , Michigan

Post by Goodysnap » Mon Aug 19, 2013 10:51 am

http://www.honda305.com/forums/carb-flo ... ight=float

Happy reading.

I was a little confused by your post. If the floats are set correctly, the level will be where it should be. Check the floats for holes and make sure they don't hang on the bowl gaskets.

HTH

Goody
64' CB77
65' CB160

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malcolmgb
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Location: Midlands UK & Cleveland OH

Post by malcolmgb » Mon Aug 19, 2013 12:47 pm

Not sure how the slow running circuit works on these carbs but you say you have turned the 'air screws' out 1 turn from 2, you have richened it!
Floats are always bench set, I know some people suggest other ways but float height is always given by manufacturers.
1977 CB400F
1973 CL175
1976 XL175 - Sold
1964 CL72
1966 CA78

LOUD MOUSE
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Location: KERRVILLE, TEXAS

Post by LOUD MOUSE » Mon Aug 19, 2013 1:38 pm

The only time I bench set the float is when I've rebuilt them and have them in hand.
If on the bike I leave them on the engine (C/CA/CB/CL72/77 and set the float.
I have a special screwdriver to remove the s;ow jet and check it when I'm in there and of course I remove and check the main jet plus I pull the slide and check the location of the clip on the needle.
All while on the engine. .............lm
malcolmgb wrote:Not sure how the slow running circuit works on these carbs but you say you have turned the 'air screws' out 1 turn from 2, you have richened it!
Floats are always bench set, I know some people suggest other ways but float height is always given by manufacturers.

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malcolmgb
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Post by malcolmgb » Mon Aug 19, 2013 4:05 pm

The only time I bench set the float is when I've rebuilt them and have them in hand.
Agreed and once set there should be no reason to keep checking and readjusting, but my main experience is with the 400f and very little can be done without removing the rack complete.
I have a special screwdriver to remove the slow jet and check it when I'm in there and of course I remove and check the main jet plus I pull the slide and check the location of the clip on the needle.
I have done this on my 175, although there is nothing special about the screwdriver, just a hex-bit in a ratchet driver, but if I was having major problems much easier to remove the carb and strip out and clean on the bench. The original poster says he has done the jets.

I'm a little bemused by his "I plan on rigging up tubes to the drains to adjust them better but I just don't know what level I should be shooting for?" surely the better way is the information Honda, the manufacturer, has published and use the float height measurement.
1977 CB400F
1973 CL175
1976 XL175 - Sold
1964 CL72
1966 CA78

LOUD MOUSE
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Posts: 7817
Joined: Mon Aug 15, 2005 8:23 am
Location: KERRVILLE, TEXAS

Post by LOUD MOUSE » Mon Aug 19, 2013 5:57 pm

Me too!. .......lm

I'm a little bemused by his "I plan on rigging up tubes to the drains to adjust them better but I just don't know what level I should be shooting for?"
malcolmgb wrote:
The only time I bench set the float is when I've rebuilt them and have them in hand.
Agreed and once set there should be no reason to keep checking and readjusting, but my main experience is with the 400f and very little can be done without removing the rack complete.
I have a special screwdriver to remove the slow jet and check it when I'm in there and of course I remove and check the main jet plus I pull the slide and check the location of the clip on the needle.
I have done this on my 175, although there is nothing special about the screwdriver, just a hex-bit in a ratchet driver, but if I was having major problems much easier to remove the carb and strip out and clean on the bench. The original poster says he has done the jets.

I'm a little bemused by his "I plan on rigging up tubes to the drains to adjust them better but I just don't know what level I should be shooting for?" surely the better way is the information Honda, the manufacturer, has published and use the float height measurement.

Mike Mullins
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Location: Demotte IN

re:

Post by Mike Mullins » Mon Aug 19, 2013 6:26 pm

I think he's referring to running clear tubing from the drains up the sides of the float bowls which would give a visible level of the fuel in the float bowl. (am I making sense ?) This however would not tell you what the float level is: it would show if the fuel levels in the bowls are the same or not. This is my understanding of the post.
Mike
"a free motorcycle is a bottomless hole intended solely for money"
66 CB 77
76 BMW R75/6
99 GL 1500 trike
75 & 79 XS 650's

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