Lean Popping?!?

[merheb]

My 1996 Johnson 130HP has what sounds like a popping sound while idle on the muffs. It pops maybe every 10-20 seconds and when it pops, a big puff of somke comes out. It seems that after awhile, it getts better but it still pops. I noticed that there is about a 200 RPM drop after it pops.<br /><br />A friend of mine mentioned that it sounds like lean popping and that it can screw up the pistons. Anything above idle is OK although this motor stalls often when shifting. It seems that it always dies when I need it the most, like when docking. Could these two be related? Is it stalling because it's too lean?<br /><br />I rebuilt the carbs earlier this year and they were spotless. The stalling problem has been going on for a long time...<br /><br />Thanks in advance!<br />Freddie

 

[mikeyzx2]

Re: Lean Popping?!?

mine does this too usually right after cold startup. and it's a kinda quieter pop, or more like a louder "puff"? I'll keep an eye on this too for more info and help bump it to the top

 

[mikeyzx2]

Re: Lean Popping?!?

^

 

[part time]

Re: Lean Popping?!?

I had a Johnson 150 doing what sounds like the same thing. Seemed you had to get it in gear quickly from high idle or it would die. It also stalled while in idle. I let it go for a while and it screwed up the pistons. I think your friend was right.

 

[mfinucan@sympatico.ca]

Re: Lean Popping?!?

I also have a 2000 150 Johnson that does the same thing I will be taking into the shop at the end of the summer. Too hot to be off the water, I will just live with the problems for now. Mine always dies just when the skiers or wakeboarders are ready to go, the odd time at the dock, which isn't pretty. Ouch! If the engine is cold forget, I can't go anywhere it won't rev at all when in gear, just bogs down and stalls. I must warm it up to about 140* first.

 

[red boat]

Re: Lean Popping?!?

I also had the popping sound you all are refering to in my 1990 XP-200. I fixed mine by cleaning the recirculation system out. there are sime small brass fittings below each carbureator on the intake manifold with hoses on them. they are small "checkvalves" mine were all blocked up with gunk. take them out and soak them in carb cleaner. air should go through them one way but not the other, if air goes through them both ways they need to be replaced. also clean the small hoses to each one of them with some spray carb cleaner.