I made some progress on the 1-75 today, but kept running into unexpected issues. The piston and cylinder measurements were as close to "the book" as I can measure, but standard rings had an end gap of over 0.025" which I thought was excessive. I have some +0.030" rings so I used the ring end filer to get to to around 0.008-0.010" gap.
I flattened the end of the crankcase on a slab of marble with a piece of emery cloth glued on.
With the piston installed (make sure the closed end wrist pin bearing is facing the exhaust port) a little grease on rod will stick the needles in place. Same process on the rod cap to hold the needles...
So far so good, but a sharp eye would notice the oiler piston is stuck in the bore...so stuck in fact that I had to remove the oiler outlet check valve and use compressed air to get it out. Well, the piston and spring turned into a UFO but not a problem as I have more in the attic. We did find the piston later on but the spring is still MIA.
With the piston, rod, crankshaft, and oil tank/crankcase bottom installed it was time to turn our attention to the fuel tank. Upon close inspection, I noticed something peculiar about the reed stops as in they were broken off and completely gone.
Back to the attic to find a good used one.
Someone had been in this saw before me, and the reed block and insulator had been modifed. The clamp is supposed to screw directly into the bottom of the tank...
...but they had added an extra insulator and so secure the reed and reed stop with a nut instead.
As a result, I only got this far today.
I should also mention that I ran into major issues with the points...something was causing them to bind and they would not close reliably. Eventually I discovered that the screw and nut for the points wire were overtightened and had tweaked the spring. Finally I had a good spark but the day was spent.
Mark
I flattened the end of the crankcase on a slab of marble with a piece of emery cloth glued on.
With the piston installed (make sure the closed end wrist pin bearing is facing the exhaust port) a little grease on rod will stick the needles in place. Same process on the rod cap to hold the needles...
So far so good, but a sharp eye would notice the oiler piston is stuck in the bore...so stuck in fact that I had to remove the oiler outlet check valve and use compressed air to get it out. Well, the piston and spring turned into a UFO but not a problem as I have more in the attic. We did find the piston later on but the spring is still MIA.
With the piston, rod, crankshaft, and oil tank/crankcase bottom installed it was time to turn our attention to the fuel tank. Upon close inspection, I noticed something peculiar about the reed stops as in they were broken off and completely gone.
Back to the attic to find a good used one.
Someone had been in this saw before me, and the reed block and insulator had been modifed. The clamp is supposed to screw directly into the bottom of the tank...
...but they had added an extra insulator and so secure the reed and reed stop with a nut instead.
As a result, I only got this far today.
I should also mention that I ran into major issues with the points...something was causing them to bind and they would not close reliably. Eventually I discovered that the screw and nut for the points wire were overtightened and had tweaked the spring. Finally I had a good spark but the day was spent.
Mark