NG engine knock

[Mike Arman]

> "Bill Green" <wgreen56 at tampabay.rr.com>
> To: <audi at humanspeakers.com>
> Cc: quattro at audifans.com
> Subject: RE: NG engine knock
> Message-ID: <000001cd46a6$5d73d480$185b7d80$@rr.com>
> Content-Type: text/plain;	charset="us-ascii"
>
> It is an engine which was used by Audi to train mechanics out in the
> Midwest. It had never been run. All the parts are literally brand new. I
> checked all the bearings cap torques on the rods and main bearing caps and
> ran a compression test before installing the engine (210 psi avg). It all
> seemed fine.



Unless you find some simple, easy, quick thing that is wrong and causing this odd behavior, I'd 
suggest you think about taking it back out and fully apart.


(I hate to be the bearer of bad tidings, and I really, really hope I'm wrong here.)


Years ago I was an instructor at American Motorcycle Institute. We had various engines and other 
components donated to us, and the students took them apart, put them back together, took them apart, 
put them back together and on and on and on until there was nothing left of them.

Students by definition are NOT yet mechanics. Mistakes get made constantly, parts get damaged, 
forced, installed backwards, sideways or not at all, and hopefully this will be caught by the 
instructor. When you have 25 students working on a dozen engines under the distracted attention of 
one harassed instructor, well, those engines are going to take a beating. And they did.

I also did ground school for over a decade at a large pilot training establishment. We went through 
a LOT of propellers, bent firewalls, engine teardowns, banged wingtips, stuff you have to ask 
yourself "How the **** did they break THAT?" and break it they did. Luckily, we never let anyone 
kill themselves, although some of the flight instructors insisted the students were trying to kill 
them ("Could you please tell me WHY you applied hard left rudder ten feet off the ground on a 
perfectly stabilized approach right down the runway centerline?")


The fact that this engine is new is great, the fact that it has been used for training is not so 
great. Please keep us advised as to what you find, but if this were MY engine, I'd go through it top 
to bottom, front to back, inside out, and prepare to be flabbergasted at what I'd find.

Again, I hope I'm wrong here, I really do . . .


Best Regards,

Mike Arman
90 V8Q