Help! Small block 360 has a knocking sound

Cudafever said
This is what i would do first! if you have a shop broom, and it has a wood handle, remove it from the brush and us it as your stethoscope. or go to the lumber yard and buy you a Wood Dowel, 1/2 diameter,4-6 foot long and us that as your stethoscope.

Yep, I use a big screwdriver or a 3' wooden dowel... both make great stethoscopes.

That lower temp on #5 is interesting, OP.