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Published 2009

Sticking Chokes
by Scott Lindley

First of all, the PO (previous owner) had put on regular fuel line from the float bowls over to the fuel nozzles. See the picture below. You will notice that the front carb line is already off. This was so I could go get the correct size replacement fuel line. I got mine from Ace Hardware as they have their own In House small engine repair shop. The stuff you want is called Tygon. That is the trade name. It is made by Norton and the part number on the box the Ace guy showed me is AAG00012. 3/16" inside diameter, 5/16" outside diameter. This stuff is made for high heat, high vibration, is gasoline proof and made for small engine applications. It will not harden for 10 years! This diameter hose fits tightly enough on my 1600 carbs that I am not using hose clamps. It is a brightish yellowish color, and translucent enough that you can see if junk is flowing through it. It cost me $2.00 a foot, plenty to do both carbs.

I removed the carbs and cleaned them in my mineral spirits parts cleaner. Any grime that was stubborn got a shot of carb cleaner and stiff brush. They turned out pretty nice. See picture below.

The outside threaded holes of both carbs had been stripped out by some PO (previous owner). See the picture below. I have a lathe and mill so made my own aluminum helicoils to repair this. You can see my repair below. 1/2 inch on the O.D. and tapped them the correct 8mm x 1.25 on the I.D. for the air cleaner mounting bolts.

In the first photo of the dirty carbs you might notice that the PO (previous owner) had wired the choke cables into their respective wells so they would stay put. I am thinking I could tap these wells for a split nut that would act as a collet when tightened to capture the choke cable.

I synchronized the carbs using my Unisyn and the old girl runs like a champ again, with chokes that work perfectly, due in large part to the Tygon flexible fuel line and a good cleaning that was long overdue anyway.


Before Stripped
Repair Bolt Hole

Machined Cleaned Up
Insert Repair & Installed