11-12-2018, 04:54 AM
(10-12-2018, 09:55 PM)Zetomagneto Wrote:As far as I'm aware Zeto our cherished suppliers are only able to offer NOS Reliant. There's nothing wrong with Reliant shells, but they should be installed with proper consideration for fit, not just bunged in hopefully. Anyone aspiring to make the C/M last should seriously consider line boring, in which case the housing can be sized to fit perfectly.(10-12-2018, 01:07 PM)fatcatvera Wrote: My check for c/m fit with the new -50thou shells to suit the newly machined -50thou c/m journal was to assemble the crank into the case using the c/m bearing only. This allows for the correct installation and clamping strategy of the c/m bearing. I did find that when tightening 'normally' (no torque figures yet, sorry) I achieved a clearance of 2thou (using plastigauge) and a freely rotating crank. If I then tighten further (again no torque figures handy) the c/m housing would then start to become oval - wider and less tall - causing the crank to tighten in the bearing.
I've had some guidance from Chris KC regarding the amount of crush of the c/m shells. I'll hopefully measure this tonight. The shells supplied to me are clearly not originally designed for the 3bearing A7 engine and most liklely are for a 3bearing Reliant sidevalve engine - the tang for one half is on the incorrect side and incorrectly positioned oil feed holes. It seems the c/m housing on a Reliant engine could be ever-so-slightly larger than the A7 engine leading to incorrect crush and this could be why I am seeing the ovality occuring.
Will report back...
Why not just get the proper shells from Jamie at Sevenworkshop