Hi Guys, I've read through alot of carb leak entries but didn't find an answer and I'm hoping to get some advise. I have a 1979 750 LTD. When the bike sits, the carbs start leaking. I had the carbs gone through by a mechanic two years ago and it ran fine. After sitting they are leaking again. I'm capable of removal and rebuild but 1) is there an easier route to inspecting cleaning replacing float needles assuming floats are ok? 2) how do you avoid today's gas causing deterioration? Drain the carbs whenever the bike is going to sit for a few weeks?
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Carb leak
- Thread starter Mcpor750
- Start date
It may be the needles leaking or it could be the fuel tubes between the carbs. Today's carb kits are terrible, some more than others. If the bike is going to sit for any length of time then run them out of fuel or drain them. I know it's a pain in the ass but at this point you would be better off pulling the carbs and fixing them properly. If you have ethanol free fuel in your area run it.
I've had good luck with all ballz racing, raddakk, and recently bought a fuel rail oring kit from 4-into-1 (I think) that I installed and successfully stopped a fuel rail leak.
I've avoided teardowns before by using Sea Foam, massive doses, like half a bottle or more to a tankful of gas. Gotta say, it can help.
It's my understanding that the o-rings and other soft parts in the Randaak's kits are of newer material that resists the ethanol in the fuel.
kirky
CB750 Addict
you need viton seals, even neoprene gets attacked by the horrible ethanol. the worst money making water absorbing racket in the oil industry today.
Do the Randakk kits have the o-rings for the fuel tubes?
PWBII
CB750 Enthusiast
A bit of info. the alcohol in the gas we get now shrinks the old-time rubber components of our fuel systems. If a bike is going to sit for a long time, think about doing it totally dry. Also, check the seal in the petcock, it may not be shutting off 100%, (that's what happens with mine). I don't remember if the '79' has screws or is riveted. If riveted, it can be drilled out & then tapped for screws.
According to the listing below I believe they do.
https://www.randakksblog.com/randakks-master-carb-overhaul-kits-for-honda-dohc-motorcycles/
If you're taking bowls off to clean the insides, the fuel rail orings should be done, too. I was told that, didn't do it, had to take them apart less than 6 months later. Pretty fun.
