I have a '70 6hp that was running pretty good, but seemed like it should have more on HP at WOT on my 11' jon. So I did spark check. Would only jump 1/4" gap at most. Bought new coils/points/condensors and have installed onto mag plate, but not run yet.
Have cleaned carb including under welch plug and all orifices. All new seals there, new float. Have not run yet since cleaning.
Compression on cold engine checks at 60T/60B, a teaspoon of motor oil in each cylinder raised this to 90T/95B. Does this tell me anything? (checked with cordless drill and 3/4 socket to spin crank, no plugs installed during test)
I have the powerhead off to replace head gasket to hopefuly improve compression. Of note is that the pistons have play on the wristpins/con rods such that I can rotate them CW and CCW slightly. Should they be perfectly stiff rotationally? This is illustrated in the 1st pic. I can rotate back and forth about 20mils (0.020 inch) on both pistons measured at the edge.
Cyl walls look good and shiny, no large scratches or anything.
Also crank can be pulled in and out axially about 10mils. See 2nd pic. Is this normal?
This motor has umpteen hundred hours on it as a trolliing motor, was never run WOT in its previous life.
Should I split the head and what should I be looking for to determine what needs replacing.
Where can I get "Sealer 1000" that my OEM manual calls out? Use 3M 847?
Thanks!
Sandor
Have cleaned carb including under welch plug and all orifices. All new seals there, new float. Have not run yet since cleaning.
Compression on cold engine checks at 60T/60B, a teaspoon of motor oil in each cylinder raised this to 90T/95B. Does this tell me anything? (checked with cordless drill and 3/4 socket to spin crank, no plugs installed during test)
I have the powerhead off to replace head gasket to hopefuly improve compression. Of note is that the pistons have play on the wristpins/con rods such that I can rotate them CW and CCW slightly. Should they be perfectly stiff rotationally? This is illustrated in the 1st pic. I can rotate back and forth about 20mils (0.020 inch) on both pistons measured at the edge.
Cyl walls look good and shiny, no large scratches or anything.
Also crank can be pulled in and out axially about 10mils. See 2nd pic. Is this normal?
This motor has umpteen hundred hours on it as a trolliing motor, was never run WOT in its previous life.
Should I split the head and what should I be looking for to determine what needs replacing.
Where can I get "Sealer 1000" that my OEM manual calls out? Use 3M 847?
Thanks!
Sandor
