First question: is your oil light working?  If so, is it on when you
here the knock?  If not make sure the sound is a rod.  I have just
the opposite problem: oil light on (a lot), but no noise???
If you do have a bad rod,  you  can do a final test, by pulling
 a plug wire, one at a time.  The rod bearing that has gone bad
will stop knocking when the plug wire is pulled.   If driven like
this the connecting rod will sooner or later break sending parts thru the top
or bottom of the block.  I've seen them go in one day, but also
more recently last an entire year.  I think this is because of the
advancement in oils we have today, and the electronics that keep
the engines running smoothly.  Good chance that if the rod goes
the block will be not be rebuildable, and you will have to also pay
the core charge.
                                                            Eric

raul lince wrote:

> Hello there,  I seem to have developed a knocking in my engine.  At first
> start up you dont hear it but as the engine warms up gets louder.  Right now
> it seems to be at the front of engine towards torque converter.  We used a
> staff to our ears touching the case to confirm this.  I guess its rebuilt
> engine time.  Is boston bobs the best for the money im sceeming to get a
> stock rebuilt 2.1 after about 12 months(gotta donate a lot of plasma over
> the next year).  How long does someone venture to guess can it be driven
> before its too far gone?  Any help out there....                      Raul
> '89 GL Money pit
>
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