Someone last week had an high idle prob on thier 69 3x2. This weekend, while removing mine to install nylon fuel bowl screw gaskets, I saw something I forgot.
I was getting a high idle when I first installed my 3x2's, even though I was exactly following the AIM and Service manual instructions. Here is what I found, and still do:
Look CLOSELY at the rear throttle arm when you put the rear throttle linkage rod the the throttle arm hole. Slowly put the rod in, and push it in SLOWLY with your finger. Watch the throttle arm closely for any movemnet (toward radiator).
You will notice that because the trottle arm linkage has a CURVED 90 gegree elbow in it (where in goes into the rear carb throtlle arm), when you seat the rod against the throttle arm to put the retaining clip on, it will pull the throttle arm on the rear carb forward slightly, giving you the high rpm.
I would adjust the rear rod by "adjusting so the rod falls short of rear throttle arm hole by 1/2 a diameter (toward center carb) of the rod diameter, then inserting", as described by the AIM and service manual. This of course, made the high idle even worse, by pulling the thottle arm open even more. Very scary when you start the engine up!
So adjust as follows: Look closely at throttle arm when you SLOWLY insert the rod. Insure it doesnt move the throttle arm when inserted FULLY in the hole. Adjust rod length until no movemment is noticed. Watch the front carb as well.
My linkage rods were bought from Paragon, and I dont know if they may made be made wrong, but I doubt it. It seems they should be made with a 90 degree sharp angle end, not bent in a curve, to alleviate this. Every other 3x2 linkage rod
I have seen has the curved end
Some things in general to be aware of:
Every time the carbs are removed, the linkage must be adjusted again.
Leaks are common around the fuel bowl inlet screws, fuel line couplings, to include the fitting that actually screws into the carb body. Unfortunatley, you really have to get all the fittings very tight so they dont leak.
The inspection hole pugs (for float level), may leak at times, but just tighten them down a snug. I use the plastic veiwing plugs, but they dont allow for very much visual inspection (plastic is a little too milky)
The main fuel inlet in the carb bodies are VERY easy to strip out. Unfortunately, thats where the fuel filters are in these carbs. I removed these filters, and placed an inline fule filter, out of site. The more you mess with these inlets, the easier they are to strip out
I was getting a high idle when I first installed my 3x2's, even though I was exactly following the AIM and Service manual instructions. Here is what I found, and still do:
Look CLOSELY at the rear throttle arm when you put the rear throttle linkage rod the the throttle arm hole. Slowly put the rod in, and push it in SLOWLY with your finger. Watch the throttle arm closely for any movemnet (toward radiator).
You will notice that because the trottle arm linkage has a CURVED 90 gegree elbow in it (where in goes into the rear carb throtlle arm), when you seat the rod against the throttle arm to put the retaining clip on, it will pull the throttle arm on the rear carb forward slightly, giving you the high rpm.
I would adjust the rear rod by "adjusting so the rod falls short of rear throttle arm hole by 1/2 a diameter (toward center carb) of the rod diameter, then inserting", as described by the AIM and service manual. This of course, made the high idle even worse, by pulling the thottle arm open even more. Very scary when you start the engine up!
So adjust as follows: Look closely at throttle arm when you SLOWLY insert the rod. Insure it doesnt move the throttle arm when inserted FULLY in the hole. Adjust rod length until no movemment is noticed. Watch the front carb as well.
My linkage rods were bought from Paragon, and I dont know if they may made be made wrong, but I doubt it. It seems they should be made with a 90 degree sharp angle end, not bent in a curve, to alleviate this. Every other 3x2 linkage rod
I have seen has the curved end
Some things in general to be aware of:
Every time the carbs are removed, the linkage must be adjusted again.
Leaks are common around the fuel bowl inlet screws, fuel line couplings, to include the fitting that actually screws into the carb body. Unfortunatley, you really have to get all the fittings very tight so they dont leak.
The inspection hole pugs (for float level), may leak at times, but just tighten them down a snug. I use the plastic veiwing plugs, but they dont allow for very much visual inspection (plastic is a little too milky)
The main fuel inlet in the carb bodies are VERY easy to strip out. Unfortunately, thats where the fuel filters are in these carbs. I removed these filters, and placed an inline fule filter, out of site. The more you mess with these inlets, the easier they are to strip out