87 Honda Accord Motor

Engine is knocking; I know I need main bearings,wondering if I should put another used engine in,or rebuild.

Car is great otherwise.

Properly rebuilding an engine will cost more than the car is worth. Your best option is to find a used engine.
The trick there is finding a used engine that is KNOWN to be good.

Yeah,that’s what I thought. No problem finding engines,but like you said,find a KNOWN good one.

Just find a used engine hopefully with a guarentee of 6 or even 12 months and cross your fingers.

I would not put much money into a car this old. If you are planning on paying someone for the installation I would send the car the junkyard.

If you can live without the car for awhile this could be a good project for a trade school, voch tech school, community college, or high school auto shop class.