You got lucky and I didn't, so the engine bottom is back with machinist for line boring this time.
It had nothing to do with "luck" what it had to do with is that I worked in the engineering trade for 40 years and was able to access if doing what i did was the right way to go.
For those who think u can support a reamer from the ball/roller bearing and it will magically make the reamer line up the bush , you cant! ...if you don't believe me just put the crank into the bearing and see how much lateral movement there is over that distance, A reamer will follow the hole
you don't use the bearing on the drive side to guide the reamer, you use the bearing race, which is held tight in the case and cannot move. Turn a bush to fit tight in that race with a concentric bore to fit the reamer pilot and how can it be out of alignment?
pretty simple , a reamer taking out only a few thou will follow the hole that is there , a reamer wont just take a whisker off one side of a hole , thats how it works in practice anyway., that is why i said that if it needs more removing from one side of the bush than the other you have to use a single point cutter as the guy in the video did
Whilst i agree to a point my main objection to 'just fitting another t/s bearing' is that
yo only get two undersizes and very often the crank only needs a couple of thou to
bring it back to round. Re-lining the steel backed bush is the best way but takes a while.
I tend to agree about the line boring with the proviso that the bush housing has not
been flogged as they very often are after running with a knackered bush for a long
Yes i should have said thats what i did ....relined a steel housing ...making sure obviously that it was a good one and only gave the new bush sufficient interference to not "grow the od " there fore make it too tight in the case . I left a few tenths on the id to give a bit to hand finish to give the desired clearance ........ from faltering memory i think i gave it 8 or 9 tenths clearance maybe a whisker more all i know is that there were no sparklies in the oil after a 100 miles or so , but remember we are talking A10 with a smaller diameter bush ID than the A65
Material choice is also pretty important to make a new lining
and yeah always take as little off the crank as you can to just clean up and make new bush to suit .......i know its not like back in the day where you could just go get an undersize bush off the shelf THEN try to find a machinist to grind the crank to the factory specified sizes specified sizes
But honestly there is so much rubbish talked on the internet about the necessary engineering required , most of it from those who have zero understanding of the trade
and yeah making sure barrels sit flat is pretty much a given ...
many so called tradesman engineers theses days cant even read a mic (unless its digital) even then they think its a precision G clamp no feel at all just from what ive seen let alone hit a size within only a few tenths on a grinder