Its been 5 years since anyone posted - maybe I'm the only one still using my 1990 lawnmower !
My oil seal finally went, and was leaking like crazy. The sump ran out, the engine stopped, but when I gave it more oil it came back to life! Amazing motor!
Anyway, I just replaced the seal:
- got the seal from amazon after getting the number from Plano Power Equipment's web site
- to get the center nut out, take the gas tank off and use a crow bar between the flywheel and either the magnetic pickup or a post
NOTE: be VERY careful to NOT go between the magnet that is glued to the flywheel! Double check the torque direction!!!!!!
- getting the guard housing off requires removing the left wheel (to get at one bolt), and removing he captured nut from inside the discharge chute
NOTE: you can try penetrating fluid, but usually the nut just spins and won't come off. I used a sawzall to cut the bolt off between the housing and the chute. This may slightly damage the guard housing but its the price you pay. This may be the most complex part of the job!
- note carefully how all the parts come off, its not immediately obvious later on how to replace them
- to get the blade clutch off, you need to compress the spring and then slide the cable end off. I found a C-clamp used for wood working worked well (the kind that slide on a rectangular shaft, then have a screw for finer control).
NOTE: my control was covered in oil and grass so removed it and cleaned it in gasoline
- I squirted penetrating oil for the inner pulley that uses a Woodruff key inside, and was then able to pull it off by hand without a puller.
Now you can access the seal!
- while others said they pried it out, I didn't want to scratch the crank so I drilled a small hole in the top of the seal (metal underneath), then slight screwed in a dry wall screw, and a slight pull got the seal to pop right out.
--- This is a good time to use compressed air to blow all the dead grass and leaves that tend to accumulate around the carburetor linkage! 111
Cleaned the receptacle well (don't spray it directly, fluid will get into the crank!), then lubed the crank and the interior of the seal, finally pushed in the new seal by hand.
When I got to putting the guard housing back, I used a normal bolt and nut, then with the sawzall trimmed the bolt end that protruded above the nut inside the chute.
RESULT: no more oil leaks!!!