Posted by Scott Gore on October 01, 1997 at 14:25:01:
Did a compression test on my 2+ year non-running 251 last weekend. 3 cylinders had NO compression that we attribute to stuck valves. After changing oil/filter/plugs and hooking up a temporary gas supply, we attempted to start with the possibility that the valves might become unstuck with a little usage. Wouldn't start, but 1 or 2 cylinders would fire and succeeded in filling up the garage with white smoke. Always a small amount of humor in these situations. Ordered the factory shop manuals last week. I glanced at them last night and wasn't impressed. On first pass, didn't see a 251 or NP420 addressed in any meaningful way. How to lube yes, spec's yes. Teardown, repair, and reassemble NO. So, here's some questions:
1.) Repair Manuals - Are there a decent set of shop manuals out there and if so, what are they and where do I find them?
2.) Engine - (Obviously the manuals would help me here). OK, all the moving parts are in the block. Take the engine out now and diagnose or will taking the head off be worthwhile? I haven't looked to see if the oil pan can be dropped without a heroic effort.
Any other suggestions?
Tks - Scott in Dallas