Author Topic: over flowing carbs  (Read 1201 times)

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Offline TRICKY174

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over flowing carbs
« on: February 06, 2017, 05:16:41 AM »
Before i blow up, run over, set fire to, sell for scrap  can anyone shed any light why my HONDA CB550/4KO) (1974) will not stop leaking petrol from the over flows, the carbs have all had new jets ect and been AQUA cleaned, this is an intermitant fault, some days its ok and runs well then for no reason it just emptys the flote bowls, the carbs have been off severel times and no fault can be found  >:(

Offline calj737

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Re: over flowing carbs
« Reply #1 on: February 06, 2017, 05:30:14 AM »
one of three reasons; either your float height is wrong, or you have a crack in the overflow tube. But, if its only intermittent, the most likely culprit is debris in the float valve.

Is you fuel tank clean and de-rusted? Small particles of rust leaving the tank will prevent the float from properly seating and cause this issue. Do you have the in tank filter installed? Are you running an inline filter instead?

Before you set fire, call me, I'll come pick it up, fix it, and sell it back to you  ;)
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline b52bombardier1

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Re: over flowing carbs
« Reply #2 on: February 06, 2017, 08:44:34 AM »
+1 on derusting the tank. I would also hasten to add that aftermarket float valve assemblies are junk. Pay the roughly 32 dollars a set for Keihin Honda real float valves and you will be much happier. I had to learn this the hard way.

Rick

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