crankshaft swap

[JDFanPa]

I think I remember from the old board that a 440/21 and 440/23lc shared the same crankshaft. Does anybody have any info on this. Wondering if I can use the liquifire crank and pistons in an X8 motor with a bad crank. Let me know if anyone has any ideas. thanks

[harleysportster]

Andy,
Technically, no they are different. They even have different part #'s. The difference is the size of the wrist pin bearing. The bearing on the /23LC piston has a outside diameter of 23 mm. The outside dia. of the /21, /22 needle bearings is 22mm. The connecting rods are different with a larger upper hole on the /23LC crank. The pistons are the same between cranks, so you need to use the 23 mm bearing if you are using the l/23LC crank in a /22 engine. The other difference is the rings around the crank to hold it in place in the crankcase. The /22 crank uses C shape rings and the /23LC crank uses full circle rings.

[JDFanPa]

Thanks Harley I will have to keep an eye out for another x8 motor but boredoom may have me try it someday. Well Im on the subject of mixing parts together do an x6 and x8 have the same stroke and crank meaning in short can I put my good 440 top end on the 400 bottom as I do have an extra x6 400 sitting here also.

[harleysportster]

Andy,
according to the parts book, the cranks are the same for :
(800)(-33103)(JDX6) AM53976
(800)(33104-)(JDX4,JDX8)AM53976
'74 JDX6 400/22
JDX8 440/22
'75 All /22
'76-'78
AM53976 CRANKSHAFT (BEGINNING ENGINE SN 741,200,000)
M53976 CRANKSHAFT (BEGINNING ENGINE SN 740,200,000)
M53518 CRANKSHAFT (SUB AM53976) (BEGINNING ENGINE SN 5,600,000) (340) (DOES NOT INCLUDE M66362)
AM53518 CRANKSHAFT (BEGINNING ENGINE SN 4,400,000) (440) (DOES NOT INCLUDE M66362)

[JDFanPa]

Thanks again Harley that certainly seems to be the way for me to go.