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2024-06-11, 20:02:05
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2024-06-08, 18:30:04
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xman has two very nice 1950's machines available - a green 1950 mk4 and black 1951 mk5 - both in good condition and running well.


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2 3/4 Crankshaft end float

Started by wobblyrider, 14 Sep 2023 at 11:49

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I am about to reassemble my 1913 2 3/4 motor after a conrod big end bolt failure.  I'm putting new bearings in the crankcase as well as big end etc. Can someone please advise the specification and adjustment for the end float of the crankshaft?
Thanks in advance.


I'm no expert on assembling 2 3/4 engines, but in general zero is not enough, and 0.020" is probably too much, so maybe aim for 10 thou or so? There is no adjustment per se, so you'll have to see how you go with/without a paper gasket between the crankcase halves, and with/without shims behind the main bearing outers as required. The key dimension is the centrality of the con rods in the cylinders. If you've had a con rod mischief, don't forget to double check that the rods are straight before everything goes back together.