What torque do I use for nylock big end nuts and the centre main bearing housing?

From memory, centre main bolts are 50lb ft. and big ends are 18 lb ft.

I agree with Ru on the torque settings but I would always use new big end bolts and rather than nyloc nuts aircraft grade all metal self locking nuts. These are usually available from, possibly amongst others, John Barlow.

If you have shell big end bearings you will probably have to grind the shell clearance flats on the big end bolts yourself. If white metal in the rod big ends, not a problem.

Location: Shropshire

As a point of interest I have used new nylocks, without incident, on all the engines I have built in the last twenty years and I am personally happy to continue using them.

me too

Sorry guys, probably me over engineering (again!) I've never trusted nylocs in a relatively hot environment but, if they work for Ru and Alan, trust me, they must work.
I have always viewed the extra 25p per nut as a small outlay for my own peace of mind but, probably money wasted!

Location: Shropshire

Ian,

I seem to remember the original nyloc nuts, when used in racing Austin 7's, often ended up with a number of little white circles on the filter. Maybe better quality now.

Tony.

Location: Melbourne, Australia.

I have never experienced it myself Tony, because I have never used nylocs inside an engine.
I don't know what the design temperature range is for nylocs but suspected, possibly cynically, that their locking function might start to let go at a relatively low temperature.
I know this won't happen with all steel self locking nuts.

Ian Mc.

Location: Shropshire

Kind of related, well big-end bolts anyway.

A few years back my lovely wife (very lovely actually) broke the crankshaft in our '28 Chummy ripping the front main lip out. Needing to use the car for an imminent summer holiday I put in an unknown spare I had recently bought. All went well until, leading a convoy of about 30 A7s, the car started making a strange (horrible) noise. I shut the ignition off quickly and the car was transported back to the campsite in the rear of Hayden Morgan's LDF Van (without it's windscreen – the Chummy that is, not the Van!).

Turning the handle over you could feel a tight spot every two turns - eventually this led to the, now considerable, mass of enthusiasts thinking it may be something to do with the oil pump seizing. Removing the sump and gauze we found the end of a split pin jammed in the veins.

Nylocks and Self Locking yes, splits pins, not for me!

Ruairidh,

You wrote "my lovely wife (very lovely actually)" what have you done that needs this grovelling (not that I am hinting she isn't lovely)- is it the inordinate time spent on restoring the Pearl?

Regarding the split pin bit in the oil pump - always use new correctly sized pins and carefully cut to length - away from the engine.

Tony.

Location: Melbourne, Australia.

35 weeks pregnant with twins (currently over 6lbs each) = mucho grovelling!