First time on the forum, Just rebuilt my Engine. Would crank but will not crank till after 10 revolutions. Took it to the shop told me it does not have enough compression. Also misfire on cy 3 and 5. I did a leak down and compression test but no sure answer of the leak . get it from intake ,crank case , . I decided to pull the heads. found after only 100 miles on this new rebuilt had wet carbon deposits n the exhaust value on all 6 cy. I pulled the engine out . Trying to find what direction to go . Some say rings others say value seals Not easy pulling an engine out of a astro van 2x. Found oil in the cylinders plus plugs wet with oily residue .

100 miles on rebuilt

 

In the first picture, it looks like you have a carbon deposit on one intake valve. It could not happen in only 100 miles. And the missing is part of your problems, that's for sure. On another note, did you torque down the heads to the exact specifications and patterns, or not?

 

hi coco, still trouble with the machine? send pm to petrik.grundmann@gmx.at thinkf we gonna solve