Try inserting the old core, if tight to go in the cable may be damaged from a overheat. Thats why I use a control cable core.
basically you insert the core from inside the boat and leave about 4 feet outside. slide the new sheath on and hols with vise grips at the end of the c=new casing
The old cable goes in just fine until the break in the sheath, which it goes through the hole instead of the sheath, but that's outside the transom. The weed eater string goes in about 3/4 of the way before or just gets stuck in something..not sure what, but could definitely be damage. I'm replacing it because it is damaged near the drive.
The 4.3 is too new of a motor to be using a old style shift cable ? Where is this hole in the sheath ans do you have good access to the rear of the motor?
Ok, cut the cable completely in half at the rear ,use a deep socket to remove the nut
carefully push what your using for a core thru and have about 4 feet come out the back. but not thru the threaded hole until you thread it for the new style cable
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