15-05-2018, 03:21 PM
Obviously crack checking is very useful to prevent critical bits being put back onto a car that might then fail sooner rather than later - and with Sevens we are fortunate in that there are generally plenty of parts around to test. But I wonder how deep some of these cracks are - is the item scrap once a crack is found? When rebuilding my rear axle, the diff carrier was checked - the old type from 1928 and earlier - and there was a tiny crack in it, so I swapped to the newer type rather than risk building it into a renovated rear axle. However, if the crack were only a couple of mm deep or less, it could perhaps have been ground out, without the component seeing undue stresses in service? This is perhaps a difficult call, as cracks usually occur at a stress concentration and a failure of this type tends to happen without warning - but I have kept the item in case one day it becomes worth the trouble for someone to attempt to repair it.
Colin
Colin