Cummins Piston-to-Bore Clearance

Looking for information on the Piston-to-Bore clearance of the 5.9L Cummins. This is information that should be in the shop manual (if I had access to one). Need to know the clearance spec. and if there is more than one piston grade. Thx.

If available I'd also like to know the bore and piston diameter tolerances.

Reply to
Perses
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From my '99 factory service manual... Cylinder Bore Diamater (Max)..........102.116mm (4.0203 in.) Cylinder Bore our of round (Max) .....0.038mm (0.0015 in.)

Piston Skirt Diameter .........................101.864-101.896mm (4.0104-4.0117 in.)

Sorry, I couldn't find anything on Piston-to-Bore clearance.

Reply to
Ed H.

Thanks for info !

Reply to
Perses

That's because they hid it :) (bore diameter-piston diameter/2=p-to-b clearance)

Reply to
Tom Lawrence

You could calculate the piston-to-bore clearance if the service manual has the bore size with tolerance (instead of the Max Dia.). Using the numbers above give an answer that I know isn't correct (.252mm max p-to-b).

As comparison, the current 6.4L ITEC Powerstroke runs 0.0441-0.0909mm piston-to-bore clearance.

Reply to
Perses

You forgot to divide by two. That would then be 0.126mm max clearance.

Reply to
Tom Lawrence

Typically, p-to-b clearance is described as the diametric clearance. For clarification, the Powerstroke clearance specs that I mentioned above are the diametric clearance.

Reply to
Perses

The nominal bore/stroke dimensions for the 5.9L are 102mm X 120mm (4.01574" X 4.7244").

Subtracting the piston diameter(s) from the nominal bore size gives a piston clearance tolerance of .104mm-.136mm

Reply to
John Kunkel

I thing you are forgetting a few .00

Reply to
sqdancerLynn

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