Rod Bearings

[Tim Rogers]

 "Steve" <juketech@swbell.net> wrote:

> In reality the timing was at 17 degrees. Pulling it back to around 10 makes
the > noise pretty much go away.
> The noise only comes on at 3250 RPM and above under light throttle. No start
> up noise at all, No noise at 7500 RPM's,

To diagnose if you have a rod bearing issue, pull one spark plug or injector
wire at a time.  Rev the engine to the range where you usually hear the noise
and see if it goes away.  If it does, then the cylinder that you have just
disconnected is the one that has the bad rod bearing.
If this does not cause the noise to go away, then you need to look elsewhere
to see what your problem might be.

Tim Rogers
-'93 NX2000 T-top
-'91 NX2000 SCCA ITS racer-to-be
-'75 Silverado tow vehicle