Z900A4 float levels

[zed1015]

The ones in my pic aren't new, they are just good/newer ones from a Z1R.
Genuine new ones can be had from ZPOWER, CMSL etc but are pricey at over £100 each but can be had cheaper if you do some google digging - Kawasaki part 16031-031 and Suzuki part
13252-43010 ( some odd NOS on ebay now at less than half that with the postage )
There's pattern ones available too .

[warren3200gt]

£106 each, that's ridiculous. £450 for a set.
Glad I've not had to buy any!!! I'd definately find a work around before paying that kinda money for a bit of brass sheet and two bits of plastic.

[sprint]

Tested one in water supported at the pivot and it was around 50/50, see attached.

Floats much higher in water supported or not. Would expect it to be lower in petrol as it has a lower density than water by around 28% so it will sink lower until it has displaced it's own weight.

Original Kawasaki seats and valves are also available at £74 each, daft prices but I guess it's old stock and not made anymore?

Kester sets should be OK, hundreds if not thousands must have been fitted so if they all exhibited to problems I am experiencing it would have been well known by now?

[zed1015]

In my pic they are in Shell V power .
New floats don't have to be that expensive if you know where to look but as long as yours don't sink too low and you can still get enough adjustment on the tang they should be ok.
Suzuki GS VM's use the same float under their part number 13252-43010 and you can get a full set of genuine for £155 delivered from Cyprus if you were quick and really needed them.
https://www.ebay.com/itm/272677643499
They've got four left there but there's others if you search.
A lot of common parts can be found cheaper if searching the Suzuki numbers instead of the Kwak ones.
Same goes for Valve guides etc.

As for the Keyster valves, they are fine and they are all i will use if i can't get Genuine Mikuni.

[sprint]

Thanks for the reply.

I think at the moment I will hold fire on replacing the floats. Hopefully I would be able to borrow a good set to see if they solve my problem before looking to replace mine?

Will fit the new Kester seats and valves when they arrive, but the logit of what is happening here if they do not solve the problem is getting daft!

[warren3200gt]

OK, in the vein of not having to spend £450 or even £100 on new floats that have greater bouancy I decided to see if there was a little or no cost way of achieving shutting the fuel flow of the needle without having the bowl fuel level too high or having the tang bent up excessively so that the needle doesn't drop straight and risks jammimg open.

Well it turns out its simple. Keeping the main hinge plate level just bend down the floats at the point it enters the float. Lowers the float in the bowl without changing the tang position from where it would be with more buoyant floats.

A quick test reduced the bowl fuel height by 4mm between these two floats. Both tested with the tang level with the hinge plate.

Straight hinge plate about 50% up the float body (excuse my less than level red line!)

Same float set with the floats bent downwards.

[Al]

I had the same problem after buying replacement float needles / seats which turned out to be 1mm or so shorter on my last carbs and faced a similar problem with the ones i have now for another issue. In both cases i found it seemed to have less risk of damage to put a 'set' in the tang in order to get it to act on the spring plunger: perpendicular,... as it must.
1mm to 1.5 mm of downward 'set', that close to the pivot point, was more than enough to bring the fuel level back to normal and take the 'side load' off the spring loaded plunger pins.
It wasnt an option for me in either case, because both types of carbs (neither of them VM) had the float valve seats: 'held in' but had they been 'screw in' types i might have considered using a second washer / gasket below them to 'restore' the 'installed' heights of the float needles.
The float needles i bought were from a reputable company and were very good quality, they had just made them too short.... or..... they were made to cover a range of models, but just not very well!!!
AL

[sprint]

Thanks for the replies and suggestions.

Clearly there must be a fundamental problem here and can only be due to a couple of issues?

1. If the current valves are not closing on the seats then this should be resolved with the new set?

2. If the floats have lost some buoyancy and are not raising enough or are not able to apply sufficient pressure to seal the valve in the seat with the tang fully set such that the valve does not drop out, then the mod that Warren has suggested may be a solution? But I would have thought that this would be a universal issue and well known by now if the floats have degraded with time as it can't be just my 4 floats affected?

I should get the replacement seats/valves in the next day or so and once fitted see if they make any difference. If not then I will try Warren's suggestion and bend the floats back without affecting the valve and drop limit tangs positions?

The suggestion of a couple of washers under the seat flange may also be worth trying, if I can find some washers?

[warren3200gt]

Andy, you should end up with two sets of washers, the existing ones on the carb set and new ones with the new valve/seat set your getting.
If your new Keyster needles are shorter than the genuine ones you might have to use both work arounds to achieve the desired results.

Post a pic of the needles side by side showing comparative lengths.

[sprint]

OK, will send some photos when they arrive.

The only concern I have with bending the floats down is that floats will then end up resting on the bottom of the bowls and may stick causing the petrol to overflow as I normally run the engine to drain the carbs?

Anyway, the first thing is to see if a solution to the high fuel levels can be found.

[warren3200gt]

Running the engine with the tap off until it dies won't completely empty the bowls. Pilot jet is higher than main jet so once that is above fuel level it'll kill the motor. Even if you used feathered choke, lowest possible pick up point, it won't completely empty the bowl.
You could measure the float drop from the body mating surface to the bottom of the float then measure the bowl depth to see if the floats would even reach the bowl bottom. Adjusting the float stop tang would resolve it if they did.

[sprint]

Still waiting on the seats/valves to be delivered, so nothing new to report at moment.

Want to try the replacements before playing around with the floats.

[warren3200gt]

[sprint]

Kester seats/valve arrived this afternoon.

Attached photo of all three sets I have.

There does not seem to be any appreciable difference in the overall length of the valves and the seats are all the same dimensions except for the ones that came with the bike, with rubber tipped valve, which has a 2.0mm dia hole, this is clearly for the Z1, A & B's which has that size. The other two have 2.3mm dia holes which are both for the Z900 & Z1000's.

On the left is the one that came with the bike, middle is from a white box set I believe I got from Z Power (which I thought were Kester?) and the one on the right is the new Kester one.

The middle one I consider to be poor quality with the sprung loaded plunger being very 'wobbly' and with a very light spring. The Kester one is well made and has a far better plunger assy.

1. Fitted the new Kester assy's with the float height set to around 24mm and the 'wet' levels remained high.

2. Looked to fit 2 washers under the seat flange but would advise against doing this as the clearance between the tubular section of the pivot is very close to the seat body and on two of them the float jammed against the seat.

3. Set the float heights to around 27mm and at this setting I achieved the 3 to 4mm below the body flange requirement, at last, see attached.

So I do believe that replacing the seats/valves for the Kester sets has had an impact and in my case a much higher static float level of around 27mm has been required against the 24mm recommended. So it does reinforce the need to do a 'wet' level test.

Hopefully now that the choke plunger seats have been done/fitted and now with the correct 'wet' float heights I will now have a rich free bike?

Thanks to all of you who have taken the time and effort to help with your practical tests and advise.

[warren3200gt]

The one in the middle looks like ebay generic shite. If you zoom in on the tip it's a rough as a 5 quid hooker. Also notice that the Keyster one has a support collar around the sprung load plunger to stop it wobbling from side to side.
The excess float height required is due to them being less buoyant so require more before shutting fuel off.
How far above level is the needle valve tang now?
Once the choke plunger are fitted fingers crossed problem solved.