why are cylinders 2,4,& 6 weak after rebuild.

Originals were reused.

Did you 'bleed'(compress old oil out) of the lifters before assembly? IF not they may be 'pumped up' to much and not allowing valves to shut all the way. Have you done a compression test or does it run enough to put a vacuum guage on it & watch?

We will try that. Yes we compressed and cleaned everything.

Post the results and I'll see if I can be of anymore help from here.

Ok, will be tomorrow before we can try it.