Johnny Stutsman writes:
> I had a leak down test done on my engine and the results said that the rings
> and valves are seriously leaking.  I am planing to start a rebuilding the
> engine as so as possible.  But what I want to know is there any way to know
> test if the bottom end is still in good shape before I drop the engine? 
> This engine has low miles, I just bought this van a couple of months 
> ago knowing it had problems but I'm afraid the previous rebuild was a 
> shoddy job.  This makes me worry that rebuilding only the top end will 
> not be good enough.
> 

 I'd say you can learn something about the condition of the bottom end    
 without splitting the cases if you check the following:

    Crankshaft end play

    With the pistons/cylinders removed, examine the cam lobes for wear by
    peering into the case with a flashlight. The wear pattern on type IV
    cams is very apparent and visible. See Tom Wilson's book for good
    representative pictures.

    Sideplay of the connecting rods can be measured and a subjective measure
    of journal clearance can be done <I'm thinking here that if one of the
    connecting rods "wags" a lot more than the others, there's a problem>

    Fit between wristpins and small end bushes.

 I don't know if there is consensus on this or not with other listmembers, 
 but I'd say that the first thing to wear out in a type IV bottom end is
 the camshaft.

 Best of luck with your engine,

 Dave