9 replies to this topic

[Ouster]

1989, HIF44 carb

Got a problem - my idle screw isn't engaging. Here it is from the side:


And here's a top down picture:


Not sure what to do - the carb came off the car before the engine rebuild and hasn't been touched before I put it back on, so unsure why the screw isn't anywhere near pressing on the lobe. Ideas?

[Ethel]

That's actually the fast idle screw. The idle screw proper is in that deep round hole in the 2nd piccy.

It does still look misaligned, check all the nuts are tight & the levers are seated fully on the spindles.

[Ouster]

Thanks. Here's a silly question - what's the difference and what one do I adjust to stop the car stalling with no throttle?

Edit: Is fast idle to do with when the car is cold and you are using choke?

Edited by Ouster, 31 March 2010 - 11:57 AM.

[Ethel]

Both would work as they both hold the throttle open slightly. Correctly setup the idle screw (one down the hole) should set the idle speed when warm. The fast idle screw should have a slight gap between it & the cam & should increase the revs when the choke is pulled before the mixture gets richer. If you look closely at the fast idle cam you'll see a little arrow, pull the choke to put that arrow opposite the fast idle screw and adjust it to set the fast idle as specified (1100rpm). You should also have a slight amount of slack in the cables so the controls are resting on the screws and not being held by cable tension.

[bmcecosse]

Yes - I think the cable is too tight - slacken it.

[mars red mike]

Second picture down the throttle return spring is missing and the throttle bracket itself looks loose on the spindle, which is probably why the fast idle screw appears to be misaligned.

Edited by mars red mike, 31 March 2010 - 02:28 PM.

[bmcecosse]

Sure that's not the choke........ The frayed cable won't be helping either - get a new one urgently. Bike brake cable inner works very well - and costs little.

[mars red mike]

Just for reference, it should look like this

[Ouster]

That picture is a big help, thanks.

The frayed cable is the choke cable, no point replacing it yet as it works fine.

[GraemeC]

Also check the throttle cable liner is properly located in the boss where it passes though the bulkhead into the car - if it isn't it will hold the throttle open slightly.