Some aftermarket front end parts are and have been junk. Sometimes good for only one year. Metals are too soft I imagine.

The bosch newer style primer pump might be manufactured in China. I sourced some there some time ago. I cannot remember if there was any notation on the boxes of made in china but the box looked like it would have been of european origin. They may also have been total fakes as well but suspect not. They appeared to be well made.

Two reasons for so many poor rebuilt alternators out there in my mind. Most rebuilding has gone to unskilled labour in mexico.Or even other countries further down the economic chain. Reason two is there are many replacement alternator parts makers out there that are dirt cheap and produce basically junk. I suspect many bulk rebuilders use their parts..

I was suprised once when in a medium size starter/alternator rebuild shop at the lack of understanding of what hooking up a scope to the alternator tester would show them was not understood.

The three phase output of an alternator under test should be comparable in phase amplitude or output if you wish. I even pulled the machine out to show them the factory labelled connections for a scope. A good used scope would have set them back twenty dollars perhaps as there was no need for anything better in a low tech application such as this. It was then too late for that operation to clean up.

Anyways because they had closed their doors as a result of two many returns under warranty and duds going out. I had stopped by to examine and purchase some parts from their now surplus inventiory.

Most of it was the junk lines of replacement parts and worthless to me. The only thing I got was some american diesel starter field coils and a batch of two dollar voltage regulators as emergency spares.

I would not count on those regulators for everyday service as I knew their track record. The constant demand for ever more profit has really caused a large hole in quality. What surviving good smaller shops there are mostly use as much original replacement parts as they can get their hands on. Plus some from the few reliable aftermarket suppliers there are.

Too many chain stores that you buy a rebuilt starter or alternator from place maximization of profit over customer reliability and satisfaction. Some of them even understand what they are doing. When the dollar margin absolutly rules an operation the customer usually looses.

Everyone has to make a living. To attempt to maximise profit fully knowing the customer will seriously suffer from the approach is seriously flawed. Greed has displaced old values totally in some quarters as far as I can tell. You want to avoid being on the recieving end.