Con rod boring , long, was; Remetalling in NW?

I've had a frustrating & disjointed couple of days trying to get the
Crossley BW1 sorted.

First cloud to appear was when I spotted that the steel dowel in the
bottom B/E cap, which secures the thick-wall steel backed shells, was
awfully close to the shiny new white metal surface.
I had a closer look at the shells and could readily feel that the top
was much thicker than the bottom so I did some measuring - the top
shell was at least 12 thou thicker in the centre than at the sides,
and the bottom shell maybe 15 thou thinner. This didn't seem right, it
meant the crankpin centre would be 12 thou below its intended point.
I phoned Malcolm at Lane Ends, he was quite affable, said if I was
concerned to bring it back. He did point out, which hadn't occured to
me before, that the bottom will probably be thinner because over the
years the cap had had bits & pieces taken off it to adjust the
bearing.
Before taking it back I decided it would make sense to check the
piston height at TDC. If that was right, there wasn't really a
problem.
The mains are tubular, the crankshaft is inserted into one side of the
crankcase & a large circular casting carring the other main is then
bolted on.Like some Lister CS engines. Here was the next snag - they
had chamfered the wrong face of the timing end main, so the square end
was facing the crank web & I couldn't get the web directly under the
liner to assemble the rod into place.
As I wasn't too happy about the big end, decided to take the whole lot
back for them to look at.
The place seems to be run by two brothers, Malcolm & another, with a
third younger guy dividing his time between the workshop & the shop
front. I'm afraid this younger guy managed to get my back up somewhat
by trying to explain with all sorts of , IMO, utter bullsh*t why it
was to be expected that the shell would be so much thicker at the top,
and kept reassuring me with " believe me, you won't have any problem
with it!".
Malcolm (one of the brothers) then got involved and showed me how they
remetal & bore con rods and why "it couldn't possibly be wrong".
In short, they set the rod in a jig in a horizontal borer with the
gudgeon pin in Vee blocks, clock the B/E central, then remove the rod,
do the remetalling, replace it in the jig and proceed with the boring.
As a method for doing direct-metalled rods I can't think of a better
way. The Crossley though is a bit more 'modern' than that, with a
proper ground housing for the shells. I can't see why the rod couldn't
be clocked from the bottom ground semicircular face of the rod (not
the cap half). I had to agree, though, I couldn't see how they could
get it 12 thou out without something being disturbed. They chamfered
the other face of the main for me, and assured me again that
everything would be fine <g>.
Yesterday I was able to actually assemble the crank into place & fit
the rod, to check the piston height. The top is supposed to be 'flush
with or just below' the top face of the liner at TDC, with an absolute
limit of 5 thou up.
Surprise, surprise, it was 13 thou above the liner!
If the cocky Scouse lad hadn't irritated me the day before, I would
probably have just taken the piston home and skimmed 10 thou or so off
the top but I felt driven to trek up to Prescot again to point out to
him that his confidence about no problems was misplaced.
I was then treated to another half an hour of utter bull***
interspersed with extremely half hearted offers to do the big end
again but with no guarantee that it would be any better the second
time(!), how long it would take etc, and more of the "believe me, you
won't have a problem...). Malcolm, who I'd guess is much more
knowledgeable and less prone to bullsh*t, was keeping a very low
profile back in the workshop.
They offered to skim the piston for me, but as I didn't have it with
me it was much simpler just to go home & do it myself. The trip to
Prescot was really a complete waste of time, I just got more irritated
with their jolly scouser & they probably have me down as an awkward
sod.
This morning was spent scraping in one of the mains, not ideal with a
tubular main as anything taken off is lost forever, one of them was
bored slightly skewed so the crankshaft was binding severely when both
mains were in place. Not an easy job either, slipping maybe 30Kg of
crankshaft in from one end, putting the other main on, turning the
crank then undoing it all while trying to keep some visible marks on
the blueing. Luckily he'd left about 2 thou running clearance, a bit
neat IMO on a 3.5" shaft, but meant that taking a bit off on opposite
'corners' doesn't leave a disastrous clearance.
With hindsight I wish I had stuck to the original plan, which was to
get Lane Ends to do the metalling, I would bore the mains myself and
my usual local reconditioner would grind the crank & bore the B/E. I
know them well enough that they wouldn't try to bullsh*t their
customers. It just seemed simpler do get everything done in the one
place.

If everthing had gone right, I would have been very happy with the
service, but wasn't happy with the bullsh*t quotient when I started
asking questions.

Moan over <BG>

Cheers
Tim

Dutton Dry-Dock
Traditional & Modern canal craft repairs
Vintage diesel engine service
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