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SU Float woes

VelodromeRacer

Jedi Trainee
Offline
Ok, more of a statement than a question...

I have sought advice from the forum on my backfire so to speak, that comes from my front carb. I recently added a header, had to replace the coil and changed spark plug wires. The group suggested to check the timing..it was 12.8 I moved it to 15 BTDC. I also richened the fuel mix into the carbs.

I still had some "backfire, only from the front carb though. Not as much as in the past and more so when cold than when the car is warmed up.

Last night I took the carb apart and noticed that it reminded me of my fav steak..cajun or blackened! I also looked at the float and bowl to make sure the needle/seat was ok and not obstructed. The float setting in the book is for 5/16", I could have driven a truck through mine which was closer to 5/8". I changed it to 5/16" and it seemed to help....could this have been the cause?

I also noticed that the butterfly valve seats ok, but just beyond that in the throat where the carb mounts to the manifold, it seems that the gasket there needs trimmed as it can be felt with my finger just beyound the butterfly??

whadduthink?
 
"Whadduthink"--Figure how's you better get that obstruction out of the way and use 7/16" float setting per figure D8----Keoke- /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
velodrome, i agree with keoke, o.k . dont get your pantys in a bunch, call joe curto at (718) 762-7878- heck get you straightened out, great guy knows his pooh pooh ,he will be glad to help. p.s went to different aviation collages together. did all my stuff with him. /bcforum/images/%%GRAEMLIN_URL%%/iagree.gif
 
On my Triumph a combination of an obstructed float valve and heavy gunk on the needle and jet created through the carb backfires. New float valves and a thorough cleaning completely corrected the problem.

The preferred practice is to set the valves and make sure the ignition system is set properly before moving onto the fuel system. It sounds like you've done that so delving into carb cleaning and rebuilding sounds like a prudent next step.
 
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