1968 33hp johnson motor help

[drewske]

need help, i recently did some work to my motor and it starts up good and idles good but it does not have the power that it used to have when i first got the motor. full throttle is not as strong as it used to be. i changed the fuel pump, water pump, spark plugs, carb kit, drained and filled the lower unit with fresh oil. compression is good. something is restricting the power and i cant figure it out. i think it might be getting to much fuel because i burned through a 6gal tank really fast but my low speed/high speed needles dont seem to be doing anything at all. any suggestions would be greatly appreciated. thanks

[Solarman]

need help, i recently did some work to my motor and it starts up good and idles good but it does not have the power that it used to have when i first got the motor. full throttle is not as strong as it used to be. i changed the fuel pump, water pump, spark plugs, carb kit, drained and filled the lower unit with fresh oil. compression is good. something is restricting the power and i cant figure it out. i think it might be getting to much fuel because i burned through a 6gal tank really fast but my low speed/high speed needles dont seem to be doing anything at all. any suggestions would be greatly appreciated. thanks

Full throttle, and power output usually relate to poor compression (weak, or poor compression between cylinders), or fuel problems (to rich, or starving). And, spark advance not working properly, or spark shorting to ground when advancing?

If compression checks out (max 10% difference between any cylinders), then fuel problems are most likely. As you haven't said anything about firing problems.

If carbs were cleaned (were they soaked), this usually means the motor sat up for awhile? Did you soak the carb well? Did you use a good compressor to blow out the high speed & low speed air & fuel pas-sages? When you replaced the needle valve seat, did you reset the float height (must be adjusted anytime seat is r&r)? When you reinstalled the idle-air mixture (low speed), did you set by manual (all carbs identically, the same)?

These simple things, if done correctly should give you good results from carbs.

If all these are in good shape, then maybe you should look at spark advance system to see if there might be some problem?

Good luck. Post back when able, if you find anything.