I have a 1971 mercury 800, timing set at 27 idling at 5. Starts on one click of the starter but idles at 1100 rpm. Put it in forward gear, goes to 900 rpm, give it just a little throttle and put it back in neutral it idles at 1700 rpm, not back to 1100.The idle screw is screwed out so it isnt hitting it. At 23 degrees the max. adv. adjustment is not long enough. The throttle plate for the primary pickup arm is adjusted all the way counter clockwise.Any help would be appreciated. I don't think it is my old age. Thank You

I forgot to mention, that my trigger went bad so I put a good distributor and trigger off a 1969 mercury 800 on it. I also put on different but the same type of shifting and throttle cables. Every thing looked the same on the 1969 distributor. Thank You Jim