Z1 carb overflow problem

[Z1Amos]

In the summer a guy came up to my bike and asked if I'd ever had a petrol leak from the carbs. I said no never had such a problem.

Since then they have leaked and I am now at my wits end trying to fix the problem, can anyone help?

Changed the float gaskets, float needle valves and seats.
No leak from the gaskets now but I get an overflow problem from no's 3&4.
This is usually about 24 hours after the bike has been parked up on the mainstand. Can't understand why it doesn't overflow immediately and why it should start a day or so later. I suspect that either the float valves are of poor quality (perhaps the spring is too weak), however I have tried 2 sets now and the problem is the same. OR the tang on the floats has wear anf the needle valve is slipping into a groove or something similar.

Anyone with any (constructive) ideas ???

Thanx in advance

Z1Amos

[img]DSC00287%20(Medium).JPG[/img]

[knut]

hi, does it happen when the petrol is turned off at the tank ?

[breakdown]

Hi, What about the floats, if there was a pinhole in them this would allow fuel to enter and cause them to sink. As you say, strange that it takes so long to show its self. I assume you've checked float heights !

[Mark Mitchell]

Hi,

I had the very same problem this summer. All that you have done i did the very same with no luck in curing the problem.

With advice from one owner club member he advised me to check the petrol tap for leaking. Sure enough after cheking there was a slight weeping from the tap when in the off position. i decided that reather than buy a re-firb kit from ZPower 25.00 i would buy a replacement tap @ 40.00. This cured the problem with leaks since.

Regards Mark Z1000A2

[02GF74]

as yu know, there are two hoses to the tap that feed the carbs in pairs 1&2, 3&4.

It is interesting that you have a problem on adjactent pairs.

The petrol is coming out of the overflow hoses?

[tlc]

In the summer a guy came up to my bike and asked if I'd ever had a petrol leak from the carbs. I said no never had such a problem.

Since then they have leaked

Was he a warlock or summink ?

[breakdown]

Track him down and beat him with a large stick

[GEZ635]

Had the same problem on a customers bike a few months ago. It turned out to be the petrol tap not turning off completely and over night there would be a leak from the carbs.Changed the tap and it has not happened since.

[Kev1R]

There is also a (well documented elsewhere on this site) issue with the carb overflow tubes which can crack lengthways.
I have experienced this and caused much head scratching at the time!

[Z1Amos]

Thanks for the replies.

Yes I think the guy who touched my carbs must have been a warlock!

Yes it does happen when the tap is turned off at the tank. Which thinking about it now it ties in with what many of you have said regarding leaking tap, probably the side that feeds 3&4. There is too much petrol overflowed for it to be just the residue left in the pipe from tank to carb.

I think I will buy a replacement tap as Mark has done.

I have tried to set the float heights put am unable to check due to lack of special tool. Has anyone made one of those? If so I'd like to buy one.

Cheers

Amos

P.S. how do you attach a piccy?
Does it have to exist on some other website first?

[bunnysZ]

re piccy yes download it on photobucket first then load it on here from there.

[02GF74]

another possiblilty is the valve seat insert or its washer is leaking?

cold just need to be nipped up or washer replaced.

you may want to clean up the seat too.

the washer does not appear to be copper btw - just tried annealing it nad it has crumbled to oblivion.

in process of making one from coca-cola can - ID 9 mm, OD 12 mm.

will see how that goes ....., fingers crossed eh?