Got a little inline 4 turbo diesel engine. Head's off and 2 of the pistons have, what seems to me, as excessive piston to cylinder clearance. I can wiggle the pistons side to side in the bore probably 40 thou or so. Seems quite sloppy to me. Any thoughts?
Well don't know the bore diameter of yours, but here's a pretty standard tolerance for 5.500 bore. Bore. Wear limit of 5.505--New minimum 5.499, New maximum 5.501. Piston skirt. Wear limit of 5.483--New minimum 5.487, New maximum 5.488.
So roughly 0.022" worst case Ontario for completely trashed bore and skirt on a 5.5" bore engine. This engine's bore is probably about 3.5" if I had to guess.
Below is an example of specifications from a little Komatsu engine. 88E Series 3.46" bore New Min .0012" New Max .0035" In Service Wear Limit .012"
Alot of engines i had apart seemed to have lose pistons but when there cold they need to have room to get hot and expand.