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Float level/roller needle/leak
Posted: Wed Nov 25, 2020 10:35 am
by Charlynsane
Hello Guys
I ave some issues on my brand new HS4 the LH float is overflowing sometimes, everything is clean and brand new
I just took a glance on this..
Someone ever experienced it?
I have the plastic fuel bowl, so it's not adjustable.. does it work? I always been afraid with fuel leaks in running engine!
Re: Float level/roller needle/leak
Posted: Wed Nov 25, 2020 4:08 pm
by Polarsilver
Had same problems a few years ago did everything to try to get this ball type valve to shut off .. solution was to go back & fit the original SU shut off valve the type with a fine pointed needle that is mounted in a fluted plastic guide .. my problems were then solved.
Re: Float level/roller needle/leak
Posted: Wed Nov 25, 2020 5:13 pm
by Oneball
As well as what Polar said;
Check the float is actually closing the needle and check your fuel pressure isn’t too high.
Re: Float level/roller needle/leak
Posted: Thu Nov 26, 2020 10:16 am
by Charlynsane
Hello Guys
I finally found the problem..
Kunifer fuel pipes.. it rust inside.. I cleaned the carbs, and I will put another filter just before carbs
Does anyone can show me their fuel filter in engine bay?
Re: Float level/roller needle/leak
Posted: Thu Nov 26, 2020 12:49 pm
by indigo
I had the same problem, would be OK for a while and then start leaking. Tried a few different needle and seats but same story. I suspect crap coming from the tank, even after I had tried to clean it out.
Put the filter in, and no more leaky needle and seats.
Need to find a more period correct filter now.
DSC_3576.JPG
Re: Float level/roller needle/leak
Posted: Thu Nov 26, 2020 1:25 pm
by Oneball
Charlynsane wrote: ↑Thu Nov 26, 2020 10:16 am
Hello Guys
I finally found the problem..
Kunifer fuel pipes.. it rust inside.. I cleaned the carbs, and I will put another filter just before carbs
Does anyone can show me their fuel filter in engine bay?
Well done.
Re: Float level/roller needle/leak
Posted: Thu Nov 26, 2020 5:59 pm
by cooper64
Get a very long inner speedo drive cable and a drill and stick it down the steel fuel line to help clean it out . disconnect both ends of fuel line first and flush out fuel
Re: Float level/roller needle/leak
Posted: Thu Nov 26, 2020 6:26 pm
by woodypup59
I guess another "benefit" of the ethanol in petrol nowadays.
Its so much more corrosive. Didn't know that it would affect Kunifer which is 90% copper and 10% nickel .
Re: Float level/roller needle/leak
Posted: Thu Nov 26, 2020 10:20 pm
by Charlynsane
Hello Guys
I found the problem, crap from the original kunifer fuel lines.. so it may rust inside?
I will try to replace it with copper line, can, it be done without removing subframes??
Re: Float level/roller needle/leak
Posted: Fri Nov 27, 2020 9:43 am
by Ronnie
Kunifer does not rust, it is a Copper & Nickel alloy

Re: Float level/roller needle/leak
Posted: Fri Nov 27, 2020 12:34 pm
by 111Robin
As said, kunifer doesn't "rust". The crap will be coming from the tank. Unless ofcourse it's a brand new tank, then it could just be a bad dose of supermarket fuel. Either way blow through the line with both ends disconnected and fit an in line filter as shown on the previous reply. I wouldn't go to the bother of replacing the fuel lines if they are new.
Re: Float level/roller needle/leak
Posted: Fri Nov 27, 2020 1:31 pm
by bwaminispeed
Yeah, the reason people use cunifer, is, because it doesn't rust.......
Those ball type valves are known to be leakers even when new.......Viton are the only really reliable needles......
Re: Float level/roller needle/leak
Posted: Sat Nov 28, 2020 8:08 pm
by Charlynsane
Thank you guys, so I don't know what was in my float chamber as I have a very efficient Sytec filter before the fuel pump..
But my lines are maybe steel?
Re: Float level/roller needle/leak
Posted: Sat Nov 28, 2020 9:26 pm
by bwaminispeed
I have seen "stuff" precipitate out of the fuel itself, and, collect in the fuel bowls.....
Also, the "red dust" quite commonly found in the bottoms of float bowls, is pretty normal, and, nothing to be overly worried about....It is very fine, and, actually goes right through most filters......It isn't large enough particles to stick needle valves open.......
How old is your fuel line......If it is original to the car, it may well be rusted internally. if it is newish/recently restored, not very likely that it would be corroded....Those two depressions right at the bottom of the float bowls, are actually debris/sediment traps.....
Since you apparently have a good filter before the pump, I would put another see through one just before the carb, and, monitor that for debris for a few tank fulls.......