They had an earlier design where the parts did not interchange with the newer design. I think the did this in the first year of manufacture. Give us the serial number and we can tell what it is. Use non detergent oil on this. The sump holds about 20 ounces of oil. Sometimes the valves and valve guides have problems. I will try to scan the manual o n this model maybe tomorrow when i can make the time. I sent you a pm.
