4 replies to this topic

[cagy]

Where is the mixture screw on a hif44 I've found the idle screw but can't find the mixture screw... Also how far in should it be? The engine is a metro 1275 with a stage 1.

And, I take it that the middle hose on the left hand side is the breather? Why have I got a screw in the end of the hose and what difference does it make either way?

[RayBoogs]

http://i381.photobuc..._adjustment.jpg

It's hard to say how far it should be in, just wind it in and out till you get a good idle.

You can test if its too rich or lean by pressing in the lifting pin:
too rich, the revs will rise
too lean, the engine will splutter and die
just right, the engine revs will rise slightly then go back to idle.

[jpw1275]

http://i381.photobuc..._adjustment.jpg

It's hard to say how far it should be in, just wind it in and out till you get a good idle.

You can test if its too rich or lean by pressing in the lifting pin:
too rich, the revs will rise
too lean, the engine will splutter and die
just right, the engine revs will rise slightly then go back to idle.

Sorry to hijack your thread but where is the lift pin?

Cheers james

[03jkirk]

the lift pin is on the right hand side near the flange for the air filter

[Ethel]

Your carb might have a part throttle weakening device. That hose with the screw could have connected to a little pipe above the throttle disc - it would communicate manifold vacuum to the float chamber to weaken the mixture. There will be another vent about an inch under the pipe if it is.