Aftermarket carb

[Rubberman 9]

I have a 92 312-8 with the M12 engine. I ended up adding a small electric fuel pump and a fuel regulator. But fuel was coming out of the carb opening. Instead of rebuilding carb , I bought a replacement. Replacement looks pretty much identical except for the choke linkage arm. The arm protrudes out beyond of the opening of the carb so it prevents me from installing the air filter bracket. I think on the oem carb, the choke arm goes up to engage choke. On this carb the arm goes down to engage choke. I mean I could use a dremel and shave down the choke linkage arm but then the choke pull knob will be backwards no matter what. Has anyone ran across this ?

[Ed Kennell 40,319]

The reversed choke lever is a common problem with the Asian carbs.    I have fixed a few by cutting off the tab and soldering it to the other side of the shaft.

[Rubberman 9]

I ended up removing the choke shaft out of the oem carb and using it in tbe aftermarket carb. Used new choke butterfly since aftermarket carb had bigger bore. 

 

it actually all worked out swapping those parts. Choke now works correctly and engine runs 
 

Edited March 30 by Rubberman

[Brockport Bill 1,820]

i think maybe Dave on ISAVETRACTORS has a video on his carb and reversing that linkage - - check his web site, or You Tube

[953 nut 57,618]

  On 3/30/2025 at 9:46 PM, Rubberman said:

Choke now works correctly and engine runs 

You are one of the lucky ones. Many of us have not had good luck with the Chinese replacement units and find it better to rebuild the OEM. 

[Handy Don 13,277]

  On 3/31/2025 at 1:12 PM, 953 nut said:

You are one of the lucky ones. Many of us have not had good luck with the Chinese replacement units and find it better to rebuild the OEM. 

Aftermarket stuff often varies on “non-contact” part specs compared to OEM--mixture screw sizes and threads, bores, internal passages, bowls, etc.--because they are built to be “bolt on” (the backward choke being a nod to more recent engines that used it that way). They are NOT intended to be sources for replacement parts to an OEM unit. 

So far (🤞) I’ve had 100% success with aftermarket carbs used intact and directly out of the box on Tecumseh & Briggs 4-cycles as well as 2-cycle Echo trimmer and Craftsman chainsaw. All were replacing units with worn throttle shaft bores and/or irredeemably congested inner passages. 

Edited March 31 by Handy Don