Morris Minor Owners Club

Although this is a Mini engine - it's essentially the same for any Minor engine. Those of you using a scaffold pole to turn rebuilt engines - take note!!
https://www.facebook.com/photo.php?v=29 ... =2&theater

we never did get a reply to the last tight engine thread.allthough I did ask

Interesting. I've not heard of fitting it without the rings. I would have been fearful of damaging the bores, but if it works then good idea, as it's difficult to check the 'big-ends' for tightness with the rings attached, particularly if the rings are new.

Rotational tightness or what may become tight can be identified before reaching that stage of assembly by use of the following basic procedures which may seem to be teaching granny to suck eggs but is most important when assembling a engine:-
Check you have the right main bearings for the crank - measure journals to confirm (crank may not be ground as stated measurements).
Check that the thrust washers are correct - measure end float to confirm. Adjust thrusts accordingly.
Check the rotational resistance of the crank in the block after fitting the bearings/main bearings caps/thrust washers and before fitting the pistons and rods.
Check that the big end bearings are correct - measure journals to confirm (again crank may not be ground as stated).
Check the ring gap in the bore before fitting the rings to the pistons. Adjust as necessary.
Check piston ring clearance in piston ring groves.
Make sure that you have the right pistons before fitting and check/measure against bore size.
Lubricate all bearings/journals before assembly.
If you fit a part and the engine becomes tight ask yourself WHY!
By all means assemble the engine bottom end without pistons rings to confirm rotational freeness.

Always assemble an engine in a proper manner and NEVER assume that things are as stated because that is when things start to go wrong! Check/Measure, Check/Measure and Check/Measure again.
The above methodology can be applied where you have any interaction between moving engine etc parts.

Check that the thrust washers are correct - measure end float to confirm. Adjust thrusts accordingly.

How would you go about adjusting thrusts?

MarkyB
You can get thrusts of different thickness.
If you only have to remove a thou or two you can take it off the back of the thrust washer (non crank side) by using a surface plate and fine wet/dry paper (well lubricated) making sure that you do not take more off one end than the other. Measure thickness at several points to be certain. Crank float should only be 3/4 thou.

if it's tight it wrong,just check it as you do each job,then you know if it's gone tight,with plugs out and the head off, the engine should turn very very easily

just check it as you do each job,then you know if it's gone tight

That is the secret of building an egine - keep checking as you assemble each part, and that way you will know if there is a problem and exactly where it is - the last part you fitted! Obviously use plenty of engine oil on every part you fit - pistons, crankshaft shells, valves, rockers etc.

On any 4 cylinder engine, it will feel slight stiffer when all 4 pistons are mid way up/down the bores, as the piston movement per degree of crankshaft rotation is at its greatest, hence the most resistance. Even so it should be possible to turn a fully assembled 'new' engine quite easily with a socket or spanner over the crankshaft nut, without the plugs fitted.

When I was rebuilding large diesel engines we used to assemble all the bearings with a smear of Castrol non creep grease or EP140 on all moving surfaces or you got boundary lubrication taking place and subsequent damage to the lead flashing on the shells.