We have 4 different types of chokes, Intregal, Divorced, Electric & Electric Conversion.
Intregal Choke
The integral choke is mounted on the carburetor, either near the top, or near the bottom. The illustration shows the choke mounted on the top of the carburetor. The thermostat is heated by a heat tube that runs down to the exhaust manifold. The heat tubes heats up the thermostat and moves the choke valve to the open position. A vacuum passage in the carburetor feeds up to the choke housing and helps pull in the heat from the heat tube. Some of these chokes will also have a hot water jacket running through, or on the thermostat to facilitate heating.
With this type of choke, the choke is not opened by the thermostat. For the most part when warm, the choke opens from the weight of the linkage hooked to it. Along with that, the vacuum from inside the carburetor pulls it open.
INTRAGAL CHOKE
Divorced Choke
The divorced choke type has the thermostat mounted in the intake manifold instead of on the carburetor. In this illustration, the arrow points to the thermostat which is covered by a metal shield. A rod connects the thermostat to the choke lever, which controls the choke valve to be opened, or closed. As the intake manifold heats up, the thermostat mounted, expands, opening the choke valve.
Electric Choke
This is a typical electric choke mounted on the carburetor, which is integral. In this case there is one wire on the choke thermostat. This is the 12v source, which all electric chokes use. The thermostat is grounded via the carburetor itself. Some electric chokes will have a 2nd wire (ground wire), which is connected back to the carburetor. When the key is on the thermostat is heated up, opening the choke valve.
Electric Choke Conversion
This is a typical electric choke conversion kit. This is used to convert an integral, or a divorced choke to an electric choke. These choke kits come with a temperature gauge that bolts on to the intake manifold, which provides more accurate choke control than with an electric choke without the gauge. The electric choke conversion kit is not used for a manual choke conversion. The choke housing must be in place in order for it to work.
Electric choke thermostats need 12v or power. Anything less will work but the choke will open slower than it should. 6v does not work. Use any 12v source that is hot only when the key is turned on.
Putting a fuse in line with the thermostat is OK, but the thermostat will work without one.
No resister should be used in line with the thermostat.
