Major engine damage from loose IAB valve screws

[PeterW]

Here's something else to worry about. There's been some postings on Prime describing major engine damage following screws coming out of the intake air bypass valve butterflies. The screws are supposed to be swaged at the end to stop them coming out, but it appears in some cases either the swaging was insufficient, or was missed. You can read the thread yourself, but preventive measures which have been discussed on the thread are either:

dismantling the IAB to check the screws are tight, possibly reswaging or Locktiting;
inspection using a bendy scope.
The consequences of failure are high, but the probability .... difficult to assess. So the risk is also difficult to assess. Probably it's a lower risk than harmonic balancer failure?

Any thoughts out there on the risk? Also a recommended practice to manage the risk? Dismantle? Inspect with a scope?

Peter
http://nsxprime.com/forum/showthread.php?t=155613

[AR]

Is really easy to take apart and a good time to maybe swap injectors for new or cleaned ones and have a general tidy up. As the cars get older and the owners demand more of them, more of this kind of stuff will appear.

[Sudesh]

Interesting read, easy to check for us that know how but generally a bit concurring I think. Would like to see if this can be narrowed down to specify year, rough mileage, general condition history of the car and service work and is it unique to any specific country?

I have an endoscope so might take a look at my own, but I don't think the scope can give an accurate result if all be bolts screws are in place, but would be good to see if any are moving out or missing. Hopefully not!

It also reminds me allot of the same issues caused by Swirl Flaps on some diesel cars

Read here

http://www.pmwltd.co.uk/?page_id=155

[NSXGB]

http://www.nsxcb.co.uk/showthread.php?9658-Little-man-has-a-big-say-in-things&highlight=Endoscope

[AR]

I kind of feel like getting in there will give youy more piece of mind.

CTSC does away with that :-)