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poor zetec running
Fishface - 29/7/12 at 03:56 PM

Well ive solved my megajolt issues but the car still seems to be running rough. I think it may be the bike carbs?
It seems to suffer a few issues such as when i blip the throttle it really hesitates at the start and more importantly seems to be running on three cyinders. I tried holding my hand over one of the carbs and could feel the suck before it started to hesitate then when i let go the revs slowly crep upto about 2.5k before dropping down again. When i hold it over the carb nearest the front of the car it seems to virtually run the same although there is a slight suck on it. Do you think the carbs may be at fault. What would you recomend.

Many thanks

Rob


mark chandler - 29/7/12 at 04:04 PM

They should all suck identically so a balance is the first order of the day (you can get this very close just using your ear and 2 foot of 1/4 inch tube, just hold at the carb mouths in the same position on each one and twiddle the balance bars until they all sound even.

If they have diaphams then check these are not split, that all the float bowls are clean, jets clean and floats balanced before you go any futher.


Fishface - 29/7/12 at 05:50 PM

thanks. Are there any guides anywhere?


avagolen - 29/7/12 at 06:59 PM

Hi, 3 out of four not bad...

When I first started my zetec on it's bike carbs, only 2 out of 4 joined the party.

ZX6R carbs have a float bowl drain / float level outlet and bleed screw at the bottom of the float chamber.
The Bike maintenance manual said that to check the float levels, connect a length of clear pipe to the outlet
and open the screw adjacent to it. The fuel level would then rise in the pipe to the level of the float in the chamber
when the pump was briefly enabled.

I went one step further and ran the engine - with the fuel pump off - and found that the carbs associated with the
cylinders that were not running did not use any fuel. All diaphrams OK. So I stripped and blew through all
jets and any other hole I could find with the airline and after a rebuild, all cylinders joined the party - GREAT.



HTH,

Len.


[Edited on 30/7/12 by avagolen]


whitestu - 29/7/12 at 07:11 PM

Float valves are prone to getting blocked as well resulting in the float bowls overflowing. As suggested a good clean will help.

Stu


mtechmatt - 30/7/12 at 06:47 PM

Yes def try cleaning up first.

I know we are a bit of a trek from you but we have extensive experience of getting Bike carb powered engines running very well, and would be happy to do so for you.

Just let me know

Thanks,
Matt


Fishface - 30/7/12 at 09:01 PM

thanks matt. If not now, in the future for sure as I have friends your way.

Cheers


mtechmatt - 1/8/12 at 09:04 AM

No worries, if you get stuck, give us a call and I'll lend you Simons carb wisdom for 10 mins

Matt