Body Channel Screw

[crotonpond]

Can anyone tell me what the purpose of the body channel screw is on my old mercury carb? It is leaking gas when running. Im assuming it must play into the low end idle adjustment? It screws into the bottom of the carb just before block intake. It is spring loaded as well.

Does this think work? They are numbers 31 and 32 on the schematics.

http://www.boats.net/parts/search/Merc/Mercury/1979/1040529/CARBURETOR ASSEMBLY/parts.html

 

[GA_Boater]

What are these screws called in the parts list? We don't allow competitor links to be displayed.

 

[crotonpond]

Sorry about that...

Actually now that i look at it again...I dont think the part is even displayed on the schematic. It screws through the bottom of the carb body. Its aligned with the throttle valve. Possibly the idle speed screw?

 

[flyingscott]

Put up a pic of the part

 

[Chris1956]

Gee, sounds like the stud that holds the choke plate. Of course, that is a stupid, wild guess.

 

[crotonpond]

See red circle

 

[GA_Boater]

A little more info please - HP and serial number. There are too many 1979 Merc outboards to guess. Right now that's all we can do.

 

[crotonpond]

1979 Mercury 40hp twin. model number 1040529

 

[merc850]

That's a return spring that closes the throttle plate.

 

[Faztbullet]

That's the throttle shaft and return spring, if fuel is leaking from it at idle you float level is off...

 

[crotonpond]

That's the throttle shaft and return spring, if fuel is leaking from it at idle you float level is off...

That is what I wanted to know. Carb is coming off tonight! Thank you.