FYI....All the 603's I've had in with this kind of 'knock' have all been on #3 or #5 cylinders....and one, on both !
Siezed rings and scored bores....piston skirt damage....liner and pistons job.
Sorry to be a bringer of bad tidings ..
For some reason, these motors seem to eat #3 in the majority of cases.....others may disagree.
If knock goes away on decel', this is most likely the problem.
BTW...What's this new addition to posts EDIT...'Multi Quote', or summat ?
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