I installed a brand new honda ac kit 3 weeks ago. I was working on the car today when I noticed a knocking noise from the bottom end. You can only hear it when the ac compressor is engaged. Is it because of the extra load on the motor? Is it normal? I didnt take the ac compressor to honda to have oil in it because it looked like it had oil already.

 

Your compressor could be knocking due to lack of oil. Only when the clutch is engaged. (cycling)

 

Its coming from the block. I wouldnt doubt the ac compressor is low on oil, but I dont know how to check that.

 

if you installed an ac compressor? and didnt add any oil ide question if it had any in it. and if there wasnt, you wouldnt hear any knocking noises cause it would have siezed up.
maybe try and turn the pully by hand and see if the shaft for the ac compressor is even attached. does the ac blow cold?- that will also let ya know the compressor is turning.

 

I can see the compressor clutch engaged it turns fine. I just hear a small knocking noise coming from the front of the block. Only when the ac is on. You cant hear it inside the car, and barely hear it with the hood closed. It doesnt get any louder when reving the motor

 

Bump

 

Screw it Ill just blow up the motor with my turbo kit, Im done caring.