I use a simple tool that I find is a big help in synchronizing my Zeniths.
I took a little plastic funnel, with a 40mm opening from my mothers
kittchen. The outlet is maybe 8 mm. This funnel fits perfectly over the
Zeniths with the flame-arrestors removed.
Into the cone I drilled a 3mm hole.
I then took a short piece of copper pipe, heated it, and stuck it through
the side of the funnel.
A transparent plastic hose is connected to this piece of copper. The hose
goes up, makes a U-turn and then goes 6" down along a wooden ruler into a
little glass with dyed water, that is fixed to the funnel.
With the engine idling, I place the funnel over one carb, then the other.
The water rising in the hose indicates the vakuum. The size of the holes in
the funnel is just right, to make the water rise sufficiently to indicate a
difference in vakuum.
If they are out of sync, I follow standard procedure, by loosening the
throttle mechanism to both carbs, and then adjusting the idle screws on each
carburettor.
Once the carbs seem to be close to sync, I close the hole in the funnel with
my finger, to increase accuracy.
If you keep funnel and water-glass separate, you could use the same system
for SU's.
The principle of a raising water column works extremely well. In principle
you could just use a plate, with a hole in it, and a connection nozzle for
the hose.
kind regards
Chris Jensen,
Denmark,
63 SII
----- Original Message -----
From: "Rocky Frisco" <rock@rocky-frisco.com>
To: <Pasanville@aol.com>
Cc: <alpines@autox.team.net>
Sent: 15. august 2000 01:20
Subject: Re: A few thoughts
> Pasanville@aol.com wrote:
> >
> > Listers,
> > Does anyone have a few thoughts on this? I was running my 1725 which
actually
> > seemed to be running fairly well, when I started pulling spark plug
wires one
> > at a time. You know, to see if all cylinders are firing. When I removed
the
> > last ones 3 then 4 the engine sounded and ran no different. When I
removed 1
> > then 2, the engine sputtered and quit. I just adjusted the valves, so
unless
> > I did not do them properly, they should not be the problem. Would out of
> > synch carbs effect it this way?
> > Also, Is there a way I can synch them with common tools?
>
> I think so. You should remove the air cleaner(s). Loosen off the link that
> locks the throttle shaft of the two carbs together. I use a rubber tube of
> about 1/4" ID to sense the airflow. I stick one end in my (more-or-less)
> good ear and use the other end to listen to the suck of the air going by
the
> bottom of each piston (this is an SU I'm talking about, but most others
are
> similar) I adjust the idle of the carbs until both are sucking equal
amounts
> of air and the idle rpm is within specs for the build of the engine (more
> modded = higher idle). Then I lock down the link between the carbs, making
> sure this doesn't change the settings.
>
> On SUs I have been advised to then set the mix, by using the lifting pins
or
> lifting the pistons with a screwdriver and then adjusting. Others have
said
> to close the butterfly on one carb and set the mix on the other one, then
> change carbs and do the opposite one, then set the idles equal. So far,
I've
> always used the first method and have been happy with the results.
>
> On my Cooper S, I cheat: I have one nice big HIF6 1 3/4" SU, so no
balancing
> is required. ;)
>
> -Rock
> --
> Ask your ISP to amend its TOS & assess fines for spamming and serious
> abuse. Clean up the net without government intervention. Pass it on.
|