took my 40 h.p 2stk in replace the choke sensor ....in doing so he replaced the plugs and checked the compression they are ..#1 is120-125 #2 is140-150 . he said the difference is maybe carbon build up. he suggested using a product called engine tuner and spay it in each cyl. and let it sit and then run it out. what do you think about this product? or is there another product out there that will clean the cyl's up. just don't want this motor going south.