Perses 2008-09-25 04:46:47
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
Ed h. 2008-09-25 04:46:59
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
Sorry, I couldn’t find anything on Piston-to-Bore clearance.
Perses 2008-09-25 08:30:26
Thanks for info !
Tom lawrence 2008-09-25 08:30:28
That’s because they hid it 🙂 (bore diameter-piston diameter/2=p-to-b
Perses 2008-09-25 08:30:42
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
As comparison, the current 6.4L ITEC Powerstroke runs 0.0441-0.0909mm
Tom lawrence 2008-09-25 08:30:44
You forgot to divide by two. That would then be 0.126mm max clearance.
Perses 2008-09-25 08:30:49
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.
John kunkel 2008-09-25 08:30:54
The nominal bore/stroke dimensions for the 5.9L are 102mm X 120mm (4.01574″
Subtracting the piston diameter(s) from the nominal bore size gives a piston
clearance tolerance of .104mm-.136mm
Sqdancerlynn 2008-09-25 08:31:09
I thing you are forgetting a few .00