1986 Other Isuzu Models exsesive oil in #1 cyl after head re

The timeing belt broke @ 236800 miles, I replaced the head, water pump, oil pump, and all belts. The engine ran fine, after it sat over night it smoked exsesively and fouled the #1 plug. I pulled the head off and found oil on top of the valves. Ireplaced the head with a rebuilt head but still oil foul the #1
all 4 pistons were struck by the valves