The two times i have been burned badly - chevy vega- al block with steel inserts- think it had a cast iron head. Drove it for 2-3 years - sold at a big loss.
but by far the worst engine - a 68 vw bug - tune-up for pay ... the damn heads stripped when I pulled the first spark plug out. Before the days of heli-coils being available everywhere. Pulled head off - heli-coiled the plugs *inserts* - put head back on - head bolts stripped at 8 ft/lbs *thats right EIGHT* - and i was using an aircraft quality inch-pound wrench to do it right.
And it only got worse from there. found out later that three years worth of bug engines, 68 in the bunch, had pretty much all been recalled/junked because of bad alloy from those brilliant krauts.
I'll never, ever touch another freaking vw. Lost my shirt, and two weeks of hard labor trying to get that thing back on the road. It ended up in the junk yard a couple of months later - owner pissed at me, blamed me for the failure - I hadn't charged him a penny. Ate all my costs.
I refuse to own or work on an aluminum engine, or engine with aluminum heads. pure crap - and nightmares of maintenance. And VERY costly to work on - the high machine shop cost for the rebuilts you got were my tip-off that they were probably al. Steel valves on aluminum seats - not a brilliant idea - and not very machineable.
Finally, brethren, whatsoever things are true, whatsoever things are honest, whatsoever things are just, whatsoever things are pure, whatsoever things are lovely, whatsoever things are of good ...
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