banjodunn
Veteran Member
G'day ken you beat me to it i was just going to suggest wrong pistons as this happened to me once on an isuzu 6bd1 the crowd that i got my eng kit from sent me a 6bg1 kit!! identical except for the piston height
i was pretty well under the pump when i was doing the assy and had checked h/gkt, brgs, etc and thought everything was ok til i went to start it and could not get it to fire 
. When i stripped it down and found out what was wrong i rang the company that supplied it and was told "not our fault you must have ordered the wrong set" when they were told to check the order i had faxed to them ( of which i still had a copy
) they were still adamant that the fault was mine as i should have checked all the components. Cost me a set of pistons and h/gkt and cost them about $5000 a month as that is what i USED to spend with them, not alot i know compared to some of the big shops but it now goes into someone elses pocket
Jon
Jon