Another Atmo resurrection

This one pretty much in and out of RATS after a few tweaks and repairs.
Rotted fuel lines + general fettles but no major rot .
Last MOT in 2012 when the new carbs were fitted but after a gear linkage issue it stood still till now ..
I still have to set the carbs up as although all brand new it runs a bit gutless...Not 100% the twins are coming in as they should. I hate carbs .....
How many Atmos on the road atm?

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It's sitting on customer supplied GAZ units and sits rather well I think

I hate carbs .....

I love em
Just make sure all the vacuum hoses are in the right places and in good condition.
Unfortunately you will never see the twin butterflies open by trying to make them work by operating them by manually turning the accelerator wheel in the engine bay ......... you can only feel them cut in by driving steadily at say 40 mph, then sharply putting your foot to the floor ....... then you will feel them cut in.
If they don't cut in, the car will just accelerate gently.

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The twins do work as I can make them kick in overriding the vac ....Just it gets to about a 3500 on the road and then that's it...no more power at all .All I can missing/ wrong atm is no burgess switch on the twins

no burgess switch on the twins

That switch is important as it stops the twin chokes working until the "accelerated idle circuit" gets tripped by the time out relay (approx 15 mins) or the oil temperature is below 15 degrees C, or above 35 degrees C......... or the twin butterflies open and with its switch, trips the timer relay out ...... Page B-41 main manual.
Also if you look at the diagram I posted above ..... item 11. ....... If the engine is cold, this wax capsule stays cold and closed, and cuts off the vacuum to the twin chokes until there is a rise in coolant temperature which opens it ...... then the twin chokes will operate.

[mettersl]

How hot was the car (an odd question right now I know, but it’s 14 degress and raining here now).
The vacuum to the twin choke is switched via the front carb warm up circuit (that’s the two pronged device on the front carb in John c’s diagram above. That’s supposed to stop second carb operation until the engine is warm.
Bridge it out and see it that makes the engine work properly.
The microswitch on the twin choke is part of the electrically controlled fast idle system for when the car is cold. It has no impact on the second choke cutting in that I can see, but John C is the expert on that circuit, it’s incomplete on my car but doesn’t seem to be impacting it at high revs.
Silly question...is there fuel getting into the second carb? I’d expect the engine to continue to accelerate even if slowly, on the single carb alone, hitting a wall could be the second carb opening and weakening the mixture if it’s got no fuel or not working properly. It does have an accerator pump so it should be easy to check for a fuel squirt when you open the butterflies manually.
These carbs are “special”. So special that I still have the workshop manual beside my bed for those sleepless moments.....
How much fuel pressure is there at the first carb...on mine the blocked return line reduced fuel pressure as the pump was trying to pump against back pressure, no flow, no pressure on this type of pump.
There is a strainer behind the single choke carb input pipe ...check for crud there too, on my car there wasnt one there on the twin choke, but it could have been lost,
Have fun....

I'm getting fuel in the twins when I force it to play ball.
All plumbing looks correct.
I've only just a mot on it and now taxed so can road test it fully now and get better idea of what's not right.....

Just a quick PS I forgot before ........ you can disable the accelerated idle for test purposes by removing one spade connector on the solenoid valve ... RHS of engine, with vacuum pipes attached. You still have the wax capsule 11, to check it is not blocked when hot.

you can disable the accelerated idle for test purposes by removing one spade connector on the solenoid valve ... RHS of engine, with vacuum pipes attached.

PPS ....... just found a pic of the solenoid valve.

Solenoid Valve.jpg