Monte -
On my conversion I wound up with serious leaks at the manifold. This was
determined by spraying carb cleaner at the junction of the
manifold/gasket/head. There should be no change in engine speed when
spraying the carb cleaner.
I wound up removing everything, cleaning up the head again, replacing the
gasket again, and making sure everything lined up properly. That helped, but
still had a slight leak. I finally increased the torque from 15 ft/lbs to
about 20 - 23 ft/lbs in small increments, applied in steps across the
manifold. That finally cured it. I also replaced all the studs and washers.
--
-----------------------------------------------------------
Marc Siegel, Charm Net LLC eMail: smarc@abs.net
Baltimore, MD http://www.abs.net voice: 410/361-8160
> -----Original Message-----
> From: owner-mgs@autox.team.net [mailto:owner-mgs@autox.team.net]On
> Behalf Of MonteMorris
> Sent: Tuesday, April 15, 2003 12:14 AM
> To: MG list; David Councill
> Subject: Re: SU adjustment
>
>
> David, et al,
> Thanks for your responses. I haven't gotten to David's suggestions about
> checking float bowls, but the pistons do move freely and the jets are
> seating properly. As several have asked: Yes, I have been adjusting the
> opening on the Unisync. Now when I put the Unisync on the back
> carb the idle
> stays about the same and the ball on the UniSync rises to about midway in
> the glass tube-where it's supposed to be. But when I attempt to put the
> UniSync on the front carb the idle rises very rapidly to 3-4000 RPM (it
> seems I read somewhere that this means the carb is too lean). I've loosend
> the linkage between the chokes and tried to enrichen the front
> carb by 4 or
> 5 flats and it still causes the idle to go way up when the Unisync is
> applied.
> What next?
> Thanks,
> Monte
>
> ----- Original Message -----
> From: "David Councill" <dcouncil@imt.net>
> To: "MonteMorris" <mmorris@nemr.net>; "MG list" <mgs@autox.team.net>
> Sent: Monday, April 14, 2003 10:52 PM
> Subject: Re: SU adjustment
>
>
> > Monte,
> >
> > My initial impression would be a massive vacuum leak of some kind. Or
> fuel
> > shortage to one carb. Having to cover the air intake to keep the car
> > running would increase the vacuum and the pulling of petrol so it sure
> > sounds like some form of fuel starvation to me.
> >
> > No doubt some details are missing. Yes, the carbs both should have
> > significant suction.
> >
> > Things to look for - first, I'd take the covers off both float bowls and
> > verify the fuel levels on both. With the tops and floats out,
> they should
> > be maybe 2/3 or 3/4 full roughly. Take both carb tops off and remove
> > pistons - make sure both jets at the base are seated similarly.
> Also, fuel
> > should be maybe visible slightly below the jet (otherwise its
> plugged), As
> > mentioned before, pistons should move freely up and down, particularly
> when
> > the dampers are not in (with dampers and oil, they are a bit
> more sluggish
> > in response).
> >
> > many people have told me how tough it is to synchronize the dual carbs.
> Not
> > so. Before I had fancy gizmos like the Unisys and the Gunsen
> tools, I just
> > made sure they were both set the same. Nuts turned down 12
> flats to start,
> > set the idle screws identically until you have the car idling well. When
> > you press the throttle, both pistons should rise in unison. Then go from
> > there. Forget the unisys until you have the carbs running reasonable
> well -
> > it is mainly used to measure the vacuum so you can synchronize the idle
> > between both carbs.
> >
> > At least thats how I see it.
> >
> > David Councill
> > 67 BGT
> > 72 B
> >
> >
> > At 07:27 PM 4/14/2003 -0500, MonteMorris wrote:
> > >The UniSync covers only one carb at a time.
> > >Being totally unfamiliar with carburation, I'm not sure how
> much suction
> the
> > >carbs should be creating, but it seems to be substantial. The car is
> idling
> > >very slowly at the starting adjustment for the throttle of one
> full turn
> in
> > >after it touches, and I must manually handle the throttle to
> keep the car
> > >running. When I switch the Unisync from the front to rear carb the car
> > >wants to dies unless I quickly cover the air intake(?) part of the carb
> and
> > >then the idle speed comes back up.
> > >Monte
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