Hi List,
Does anyone know the difference between a CS 3/1 and a CS 5/1 crank
shaft?
Is it just the diameter of the big-end journal, hence different
con-rods and white metal bearings for the 3/1 and the 5/1?
Any assistance appreciated.
Ken
The later part nos for the cranks and big end bearings are the same whilst
those for the rods are different.
I would guess that the only difference between the rods is the width across
the little-end (as a consequence of the different bore and thus piston-boss
size).
Worth bearing in mind that early 3/1 and 5/1 (about first two years?) shared
the L crank with 1 3/4" main journals. IIRC when the CS switched to 2" mains
so did the L.
hth
Thanks Ronald,
None of my 3/1 engines are earlier than 1948.
The parts manual I have shows the following:
3/1 crankshaft 5-1/E101C
5/1 Crankshaft 8-5-I02
3/1 Big end bearing 5-1/D8A/9A
5/1 Big end bearing 5-1/D18/19
3/1 Con-rod 208/18
5/1 Con-rod 5-1/D5
Does a later manual show the crankshaft to be a common part i.e.
8-5-I02 ?
The Lister parts numbering scheme must have kept many a storeman
puzzled, and many a customer bewildered.
Thanks in advance,
Ken
Nek
Yes it does. Still later the 5/1 switched to steel-backed shell bearings
which may well explain the other differeences. BTW I'm referring to the
reprint manual/parts list available from
formatting link
This whole area is Peter Forbes speciality so you will probably find more
here
Are the (3/1 and 5/1) Con Rod lengths the same?
Perhaps the stroke is slightly greater on the 5/1, requiring a different
crankshaft?
Mark
Ken_Boak wrote:
My 3/1 dates to 1937.
As a guess I'd say the big end dia will be greater on a 5/1 than a 3/1,
I'll measure mine up. The strokes are the same for both the 3 and 5 @
5.5"
The shells are white metal on brass/gunmetal/bronze on my 3/1.
for both the 3 & 5 (and for the 10/1!), so the difference could be just
the big end od.
Simon
My big end diameter is 2.25" x 2.375" width, my father suggests the
width of the big end bearing could also be greater on a 5/1 but having
the same diameter, giving a larger working area.
I'll have a look at the cranks we have in the workshop and see what size(s) they
are.
Width should be the same.
Peter
--
Peter & Rita Forbes
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