High Idle on 69 230

[mslipac]

My idle is about 1500rpm cold or hot

The Flaps on the carbs are wide open at idle and when I close them manualy the idle comes down to normal.

What do I check?


Thanks

Mario

[Mark DiSilvestro]

I'd first check for vacuum leaks, then see if one or both of the fast-idle cams on the chokes are sticking then check the fast-idle adjustment screws (you might need a small mirror on a stick to see the fast-idle cams and screws) Of course, check the carb idle-speed screws.

Happy Motoring, Mark

[psfred]

Check to make sure the linkage moves freely and the return spring for the throttle is good.

Are you talking about the very top flaps, just under the air filter? Those are the chokes.

If the throttle valves (way down by the manifold flange) are haning open, it may be a sticky throttle posistioner or bad switchover valve or speed sensor, too -- the throttle positioner is to keep the throttle valve from snapping shut and sucking gas down the carb on deceleration. Should be de-enrgized below 200o rpm, or is it 1500? Whatever, try holding the throttle positioner off the linkage and see what happens.

Peter

[mslipac]

yes it is the top flaps that are sticking open

[psfred]

Very top flaps are the choke, they are supposed to be open except on a cold engine, and then the open up pretty quick (electric heater on the opening spring). The give a very rich mixture for starting and then gradually reduce it to normal as the engine warms up.

If the throttle valves were stuck wide open, believe me, the rpm would be much higher than 1500!

Pushing them shut will reduce the idle speed, but you will have black smoke rolling out the back.... The problem is either a vac leak or something holding the throttles on fast idle.

Peter