My Cat 27 #6298 is on the hard
for the winter and I have several projects I want to do in the spring. One is to replace the, probably, 30 year old stuffing box packing. I remove the nut, out of the water
of course, measure the shaft (1") and getting the inside of the nut proves difficult. The major Dia. of the external thread is 1.5". So the leave the difference as 1/4 packing. However, 1.5, or somewhat less, is the root dia of the internal thread.
The minor dia of the nut is going to be @ 1.4 assuming a 12 pitch
thread. I can't actually measure the pitch
but is appears to be unf. Standard course thread for 1.5 thread is 6 and there are definitely more threads per inch than 6. So 1/4 (.25) packing may be too tight. 3/16 (. 1875) seems a bit loose. I've search around the interweb forums
and some boats seem to have 1/4 and other 3/16. So, will 3/16 expand enough to fill the void?