by bgsengine » Mon Oct 10, 2016 8:58 pm
Yes that'd be the guidance - if you can get the old push rod out and have all the pieces, if broken, to put it fully back together and know you got it all, then sure, magnet can do the job.. scope can as well - *if* someone has a scope (not everyone does) then I'd also see no reason to tear the engine down.. but if you got pieces but not everything to put a pushrod back together, or if you find the push rod fallen down into the crankcase and bent or damaged on the end that was in the crankcase, I'd still strongly advice a tear down and inspection - you could not see if cam is bent (or cracked) with a scope, and be 100% certain... I didn't see where KE4 was discrediting anything you had said - just a clarification (which is further clarified above) - just because you can get broken pieces of push rod out of the crankcase, and/or happen to have a scope handy for an inspection, does not necessarily mean you won't have an issue when you put it back together - and if someone puts it back together and wastes a head gasket / gasket set only to discover the governor gear had damage that just could not be seen by the borescope (been there done that) - it does not save them any time at all - - you do not always have to tear down the engine just from a thrown push rod, but it is good to make sure to make them aware of the possible issues to consider before just zipping it back up - if there is any reason whatever to suspect internal damage, whether or not a borescope shows no damage, then best bet would be to do the teardown - its only one extra gasket and seal and some additional time invested - cheap insurance as opposed to taking a chance that the cam (or governor gear) has damage that results in a catastrophic failure at RPM
I had one myself - and the intake pushrod came out whole although it HAD gotten down into the engine - but since it was not broken to pieces and only a slight bend to it, I didn't think anything of it at the time - put it back together, fired it up , it started out fine, had governed RPM, then all of a sudden it ran away (overspeeding) followed by a piece of governor gear coming through the side of the crankcase. - That's typical of my luck... but at least failure happened in the shop and I still sold a re-power engine (but had to eat the time and labor and parts to do the head and valve job on the old engine) - upon tear down and inspection of the governor gear pieces, you could see where there was a very fine hairline crack that was on the bottom side of the gear (you'd never see it even with a boresope) that started the failure...
How poor are they who have not patience. What wound did ever heal, but by degrees? - Iago (Othello Act II, Scene 3)