AAR Revisited

[iboughta911SC]

Ron,
Do you have any resistance wire left I can purchase from you? Pelican's minimum has jumped way high.
Charles Rahm in Dallas, TX

[E Sully]

I stumbled across this thread and a TSB regarding the AAR.
It seems the AAR was changed due to low ambient temp idling issues from a 33 ohm to a 26 ohm unit.
If the idle is still high tap the end cap in max of .5mm

[Hokie6]

I recently had to troubleshoot the AAR in m 930, and this thread has been extremely helpful. However, my AAR was "sticky", in that it would not open fully open when cold, and then when heated, it would snap shut after a period of heating. After dissecting it, I found that there was a divot that had formed into the metal "beam" which was causing the stickiness. I was able to slightly bend the shutter door finger, and also rotate the beam down, such that it tracked away from the divot. It's hard to believe that it would form a divot like that, but it works much smoother now after re-adjusting the alignment -

[ahh911]

Hokie,

I find your "window" in the 930 to be very different from my SC. As the AAR closes, your 930 goes through a different warm up air bypass profile. I don't feel so bad now having dremelled the slightest notch to extend the cold elevated rpm response in winter for a few more minutes, though in my case a proper calibration might have been better. In any case, very cool, learn something everyday.

Phil

[RV Flyer]

I've been going through the CIS on my '78SC and getting things dialed in, and found that my AAR had lower resistance (about 16-17 ohms) than I think the spec calls for. Lower resistance would lead to quicker heatup and a more rapid transition from the greater cold start airflow down to normal operating conditions. It took some poking around but I found insulated Nichrome resistance wire on Ebay, 25 foot lengths in various resistance per foot values (which I think should just be a reflection of the wire diameter - smaller diameter = higher resistance). Ebay seller is OzarkAssemblies in Missouri, price about $1/foot.

I'm going to rewire my AAR for about 30 ohms, which should lengthen the transition time, which is my goal. Right now the engine seems to transition a little too quickly.