So I'm a Chevy guy that bought a Ford. The truck gods said screw you and blessed me with head aches. I bought this truck as a unfinished swap. The guy I bought it from said they got it running but it would die after 30 seconds. When I picked it up the intake manifold was off and wiring harness was yanked out. Dropped it off at the mechanic cause I had no time to tinker, he' had it for month got it back together and now the problems start to show, over the phone he turns the truck over and it sounds fine 100% fine for a couple of cycles then it starts to slow down then clunk it "locks up", he says that if you try it again right away it won' crank, bust you leave it for 5 mins then try it again it'l do the same thing. He' saying that he thinks a crank bearing is spun or corrded, but to me it just doesn' ad up I would think that if a bearing was done leaving if for 5 minutes wouldn't benefit anything and it would still be hung up in the position it "locked up" in. If read lots about this older 5.0's having problems with not putting enough amps to the starter being a newer starter need more amperage, or maybe bad grounds??, even a relay?? What do you guys think I'm gonna try to get it going my self this coming week any suggestions would help,
Another guy with a broken ford
thanks

 

I would think you will get a few suggestions on this, but it won't be the first time I was wrong.
What if,,,,, you made sure you could turn the engine over just using the alt pulley while the engine was cold. ( I believe the nut size on the alt pulley is 15/16). Now you have some idea how much force it will require to turn it over.Then after you try starting it and it quits, shut the key off and see if you can still turn it over as done earlier. If you can , I would think there could be a problem with the starter system.
If you can't budge it , now you need to determine if the problem lies within the engine or possibly the trans or maybe something the belt turns. By disconnecting each one you should be able to pin down which area is causing the slow/ no crank problem.
There may be other ways to determine the cause , but this is what I would try.

 

thanks hanky the mechanic had mentioned it was hard to turn by hand but I will try myself I am just not willing give up on the old girl yet

 

Usually when the rotating assembly, bearings etc are damaged to the point of a seizing condition, an oil sample taken may contain suspended metals, or there maybe a collection of debris on/at the pan drain plug.. Cutting open the oil filter for inspection may point a boney finger as well.

Also, an oil pressure test during cranking may point to a system fail, meaning little to no pressure...

Hydro lock can be a possibility, and of course cranking components. If the battery is spec, and cabling tight/solid, if the engines rotating parts are cause, generally the starter will rapidly overheat, or the cables will go overtemp at the very least..