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icemann427 icemann427 is offline
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After reading your last few posts, 9307004, I'm, now, guessing you are not too mechanically inclined or really know the 930 engine. As such, I apologize for my previous abruptness.

With that being said, there is no way a 930 engine will run quietly like a modern engine. Modern engines have hydraulic lifters which, for all intents and purposes, remove all of the space between the camshaft, rocker arms, and the valves, which also makes the engine run quiet. While hydraulic lifters do yeoman work for engines which run in a normal/lower rev band/envelope, back in the day performance engines only used mechanical lifters or were overhead cam engines which did not have lifters. On overhead cam engines, the camshafts come in direct contact with the rocker arms to get the valves to open (they automatically close because of their springs). When a 930 engine is first started, the contact gap between the rocker arms and the valves is big and will make a fairly loud clacking noise until the engine warms up and that gap is reduced. However, even when the gap is reduced because the engine is warm/hot, the valve train will naturally and always still make noise because that is how it is designed.

Do not fret that you hear this noise. It is supposed to make it.

The only reason you should even do a top end refresh is if you are burning oil; and/or if you do a leak down test and a compression test and the numbers are not what they are supposed to be.

A top end refresh can be as simple as doing a valve job. Or could involve changing the piston rings, the pistons, and could even include the rod bearings, too, since you can get to them without separating the crankcase (however, unless the tests show that you might need piston rings or the mechanic is suspicious of the condition of the pistons, there is absolutely NO need to pull the cylinders to get to the rod bearings).

Unless you visibly see burnt oil coming out of the exhaust on a regular basis as you drive (and I am not talking about smoke upon some start ups [even though that could be an indication of needing valve guides] since some oil accumulation can occur in the turbo), and/or the leak down and/or compression tests are bad, there is absolutely no need to even consider a top end refresh.
Old 03-15-2017, 04:53 PM
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