[Grazman]

Hello,

Just wondering if I can check the float levels on my cb175 with the carbs in situ,or if I take them off, do I have to remove the petrol tank, as the inner carby mounting bolts are hard to get a spanner on.

thanks,

Grazman

 

[Richard_Pitman]

Carb removal:

No need to remove the fuel tank.

You just need a better spanner !

A stubby 10mm ratchet ring spanner works for me. I like Halfords Professional tools, but plenty of others out there.

For example: https://www.machinemart.co.uk/p/5-piece-stubby-flexible-ratchet-ring-spanner/

 

[jd50i]

I don't know about your carb design but on my bikes, I can use a short piece of clear tube attached to a hollow, conical shaped rubber piece, came out of a car vacuum test set I had. I remove the bowl drain screw and insert the rubber piece and hold the clear tube up and turn the fuel on. Hold the tube up next to the bowl and see where the fuel level is.

 

[Grazman]

Thanks Richard,thats a good idea.i need to check the float level again as it keeps overflowing, so I must be doing it wrong. I have read the how to do's on this forum , but its difficult to tell when the tang is just touching the valve.i will keep at it , they say practice makes perfect.

 

[Grazman]

Thanks jd50i, I don't think I can do that with my carbs, but will have a look. Thankyou.

 

[jd50i]

I should add the picture is from my Sabre, it is easier because it has a drain valve and not a drain screw like my twins so I just attach the tube to the drain nipple and open the valve. On the twins I have to use the conical rubber piece and hold it in the drain hole.

 

[Richard_Pitman]

i need to check the float level again as it keeps overflowing,

In my experience, an overflowing carb is just as likely because of a faulty float valve.

I've had no end of trouble with those, either leaking and causing an overflow, or sticking shut and starving the carb of fuel.

I ended up using pattern (Keyster) float valves in original valve seats, only combination that didn't either leak, or stick shut.

 

[Grazman]

Thanks Richard, I am dismantling a carb at the moment, and displaying my ignorance I cant figure out how the internal spring of the float valve works. the spring moves in and out ok, but when I put it in the valve body it seems too short to actually do anything. I am sure they are the originals.i have read that when measuring the float level turn the carby body until the tang just touches the valve before compressing the spring, but there seems to be no spring resistance in mine.Could you please enlighten me.

Thanks.

Grazman

 

[Grazman]

Hi everyone, please disregard my previous post. I am embarrassed to say I am an idiot as I have just realised the valve was upside down.

Thanks Grazman

 

[jd50i]

Glad you found the problem and bravely posted it so others can be aware of this.

 

[drydreamer]

You know of cmsnl for the exploded views which may help.

Most carb fuel levels can be "seen" via the plastic tube and drain screw method, some even using the fuel level shown relative to a reference point, usually the line made by the float bowl to carb body joint. Twins etc, can easily be compared this way.

Have you made a float gauge ?

Without checking, your carbs have the float chamber wire clamp or screws ?

I tend to replace the screws with allen bolts these days, makes removing the chambers easy with the carbs in situ, for servicing and cleaning etc..