Hi Members I have a reno 750 1962 made and need to know how to set the position of the rotary disc valve to dead cold position. This is the rotary plate that is driven by the thermal spring. I have searched high and low but can find no info on setting of the plate when the engine is dead cold.
- Thread starter octavia
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JdeW
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I'd say the choke valve in dead cold position is open like in normal driving circumstances.
When you start in cold weather the bi-metal heats up and closes the choke valve and enriches the fuel mixture for cold start. After a few minutes the bi-metal cools down and opens the choke valve for normal driving and mixture.
It's like a manual operated choke, in cold conditions you close the choke valve to start the cold engine, when the engine warms up you manually opens the choke valve.
By the way, in 1963 Renault discontinued the electric operated choke and changed everything to manual operation.
When you start in cold weather the bi-metal heats up and closes the choke valve and enriches the fuel mixture for cold start. After a few minutes the bi-metal cools down and opens the choke valve for normal driving and mixture.
It's like a manual operated choke, in cold conditions you close the choke valve to start the cold engine, when the engine warms up you manually opens the choke valve.
By the way, in 1963 Renault discontinued the electric operated choke and changed everything to manual operation.
Andy McGhee
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Hi
Is this the type of carburettor?
Is your car a Renault 4 or a 4CV?
You could also try the Renault Classic Car Club Facebook page.
Is this the type of carburettor?
Is your car a Renault 4 or a 4CV?
You could also try the Renault Classic Car Club Facebook page.
JdeW
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Nice picture @Andy McGhee it could also be a Zenith 28 IFE but the electro mechanical principle is the same
André4Renaults
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This form of automatic choke was not Renault's "finest hour" and, as has been said, was discontinued from the nearly 1960s. Workshop manuals have suggested conversion to a manual choke arrangement. The theory of the system was good, but its application didn't work too well, relying on a peculiar oil pressure switch to control the flow of current through the bi-metallic strip. Everything operated on 6 volts, which works well if properly maintained, but is inherently weaker than a 12 volt system.
angel
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Hi Octavia. I guess you are referring to a 4CV with the Solex carburettor that doesn't have a choke flap and has an exhaust gas heated bi-metal spring. I think this will help you:
@JdeW: all bi-metal chokes work in reverse to what you wrote. When cold the spring forces the choke flap to the fully closed position, then when the engine is being started, current is supplied to a resistance that slowly heats the spring. When the bi-metal spring gets hot it pushes the choke flap gradually to full open position. When the current feed is interrupted (and engine bay cools sufficiently, too), the choke flap is retracted again to closed position.
@JdeW: all bi-metal chokes work in reverse to what you wrote. When cold the spring forces the choke flap to the fully closed position, then when the engine is being started, current is supplied to a resistance that slowly heats the spring. When the bi-metal spring gets hot it pushes the choke flap gradually to full open position. When the current feed is interrupted (and engine bay cools sufficiently, too), the choke flap is retracted again to closed position.