How do I install the cam back into the engine, I cannot see any timing marks on the crank. There is a single hole, but try to line that up with the dot on the cam causes interference. I have looked at the manual, here
http://www.cpdonline.com/692509.pdf, I don't see anything to help me. This is my dad's attempt at a repair of an oil leak, so it came to me in a box, so the parts were apart when it came to me. Help please!

Thanks in advance.

Look closely at the gear on the crankshaft, if it's loose and can be slid off of the crankshaft, it may be upside down and the mark hidden. On some of the gears the mark is a bevel on one of the teeth.

I have looked it over closely many times now, I tried again, I still don't see anything at all. The gear is not loose at all, not even with light prying. Can I do it by using an indicator through a spark plug hole, finding tdc? Where would the cam lobes end up?

thanks

You could set it with the piston at TDC and drop the cam in so both of the valves are closed, but there is a possibility that you can be off one or two teeth. The engine would probably run, but won't run right if it's not where it's supposed to be.

You might want to try looking at the gear with a good magnifying glass to see if you can see where the mark was, it's probably been polished down from running, but there may be some indication of it under magnification.