Powerhead jerks & pops

[Jim1942]

I have a Johnson 33HP, 1968 motor. At slow speed, it pops through the exhaust and the engine jerks hard. The lower gear case in not on the motor yet. Am using a submersible pump to circulate water. Do I need the lower end with propeller connected for testing?<br />Thanks,<br />Jim

 

[rwise]

Re: Powerhead jerks & pops

In some cases you may get a run away, the engine could go over rpm. not a good thing!

 

[Jim1942]

Re: Powerhead jerks & pops

I ran it at start to low speed,at about 8 or 900rpms it started kicking. It did not over speed. Do you think I need to put on the lower unit to run a true test. I also replaced the coils, points, condenser.

 

[Walker]

Re: Powerhead jerks & pops

Sounds like the classic lean condition sneeze. Turn the adjustment needle counter clockwise 1/8 turn at a time untuil it stops sneezing. Then fine tune it til you find the sweet spot where the engine idles the best.