Throttle body adjustments (edits completed)
Throttle body adjustments (edits completed)
I'm trying to baseline the adjustments on the throttle body. But it seems things are very hosed up.
The throttle shaft won't close enough for the cam button to hit the cold/fast idle cam.

In this picture you can see that the fast/cold idle screw is just touching the thermowax piston. And so the cam roller (pale green dot) is aligned with the wrong mark on the fast idle cam. And the cam roller isnt touching the cam and this is at idle.

From this angle you can see that the fast idle adjustment screw is all the way in and the cam roller is pretty well aligned with the correct mark on the fast idle cam. But the roller isn't touching the cam.

In this picture you can see I've lifted the fast idle cam simulating the piston extending as if the engine where hot. but you can see it wouldn't make any difference because the roller wasn't touching the cam anyways.
The butterflies are closed and seem to have right amount of opening at idle, but while the FSM gives a spec for the opening it doesnt say how to measure it. And my feeler gauges dont like the curve so I'm guessing they mean to measure it with a pin-style feeler gauge.
I adjusted the normal idle screw (the adjustment screw on the right side of the bottom illustration on page F2-35) but it doesnt seem like the plates move much so just a bit of unscrewing and the head of the idle adjustment screw just lifts up above the plate that it presses down on (see illustration on bottom of F2-35)

Also on F2-35 in Throttle Valve Clearance step 2, it implies you can make some adjustment. But the text is cropped like they had a big editing fiasco. I took the bolt off shown in the 2nd illustration from the bottom. But nothing appeared to be adjustable.
Any ideas?
Thanks,
Jim
The throttle shaft won't close enough for the cam button to hit the cold/fast idle cam.

In this picture you can see that the fast/cold idle screw is just touching the thermowax piston. And so the cam roller (pale green dot) is aligned with the wrong mark on the fast idle cam. And the cam roller isnt touching the cam and this is at idle.

From this angle you can see that the fast idle adjustment screw is all the way in and the cam roller is pretty well aligned with the correct mark on the fast idle cam. But the roller isn't touching the cam.

In this picture you can see I've lifted the fast idle cam simulating the piston extending as if the engine where hot. but you can see it wouldn't make any difference because the roller wasn't touching the cam anyways.
The butterflies are closed and seem to have right amount of opening at idle, but while the FSM gives a spec for the opening it doesnt say how to measure it. And my feeler gauges dont like the curve so I'm guessing they mean to measure it with a pin-style feeler gauge.
I adjusted the normal idle screw (the adjustment screw on the right side of the bottom illustration on page F2-35) but it doesnt seem like the plates move much so just a bit of unscrewing and the head of the idle adjustment screw just lifts up above the plate that it presses down on (see illustration on bottom of F2-35)

Also on F2-35 in Throttle Valve Clearance step 2, it implies you can make some adjustment. But the text is cropped like they had a big editing fiasco. I took the bolt off shown in the 2nd illustration from the bottom. But nothing appeared to be adjustable.
Any ideas?
Thanks,
Jim
Last edited by vrracing; Aug 13, 2008 at 06:20 PM.
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