mercarb choke

[stevenj]

1987 G.M. 3.0 litre, with what I think is a mercarb?, choke is free and moves well, my question is what force pulls or forces the choke to the closed position? If I am thinking right the electric Bi-metal is an opening force. am I correct? is there supposed to be a spring of some sort to force it to closed position, I have read on choke adjustment, but maybe overlooked something,
Reason for asking is I can start the motor cold just have to play with the throttle a little. I plan on rebuilding the carb this winter or even just buying a reman. carb.to be on the safe side for next season.

 

[cr2k]

Re: mercarb choke

Actually the coiled flat bi-metal spring in the choke housing is what holds the choke closed. Put it on so it is behind the choke tang in the housing and rotate it until the choke is closed. When this spring heats up, either electrically or from exhaust heat (depending on what system you have) the spring will relax allowing the choke butterfly to open. There is a weight in the linkage system that pulls the choke open.

If your carb has one idle screw it is a Mercarb.

 

[Don S]

Re: mercarb choke

Reason for asking is I can start the motor cold just have to play with the throttle a little.

You do realize, that having to play with the trottle a little is quite normal on carbed engines.
These aren't EFI like your car/truck.

 

[stevenj]

Re: mercarb choke

Thanks for the replies,the choke plate does not pull to closed when given throttle, making me have to goose the throttle a few times to keep running, then I am able to set it to a high idle 1500 to 1800 for a few minutes at which point once the engine warms I am able to return throttle to full
idle position. Don I take the wife with me and she is really admiring the larger fancier boats docked in the clubs down river from us so a newer boat with
EFI may be in my future