engine choking out at WOT

ryan04

Petty Officer 1st Class
Joined
Jan 26, 2005
Messages
212
Hey guys, this should be the last question before summer is over. I have a 1972 125hp johnson, about a month and a half ago I through in a set of carb kits on this thing in hopes it would improve idle problems. It idles ok, but doesn't seem to be a nice steady idle. It sits there and idles then sounds like it skips a bit then evens out then skips again, this goes away once you are in gear and moving. The next problem is when I open it up right off the bat it starts to go then sounds like it's starving for fuel or something. It just kind of chokes and doesn't speed up unless I ease back on the throttle then it feels good again. From there if I want to go faster I have to slowly ease it forward and most times it will studder but slowly speed up. In some cases it's been studering then like somebody turned a switch it will rev up nice and take off then kind of choke out again. Do I clean the carbs again, even though I did a very thourow cleaning and kits. any thoughts?
 

cr9c1

Petty Officer 2nd Class
Joined
Aug 28, 2006
Messages
146
Re: engine choking out at WOT

Strangley enough, I went to the local outboard shop to purchase a mint 1973 Johnson 9.5 HP. I demanded a test run before paying cash for the outboard which he obliged.

Acted the same way. So I took it back and told him it ran like *censored:)*

After he drilled his mechanic about replacing coils, points, and condensers as a packaged deal, he discovered a bad plug wire that was working intermittently.
 

ryan04

Petty Officer 1st Class
Joined
Jan 26, 2005
Messages
212
Re: engine choking out at WOT

That's very true, I heard a ticking noise one night two weeks ago and noticed that my #plug lead was rubbing on the flywheel and it wore through and spark was jumping to the flywheel. I replaced it and the engine was immidiately 100% better. So now it's just this stupid problem. It did this years ago when I first took it out of storage. I got it tuned up and it was perfect for about an hour then it did it for a second then didn't do it again for months, then the next year it just got progressively worse to where we are today.
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: engine choking out at WOT

sound like clogged high speed jets, in the carb, and link & sinc. or a weak fuel pump, is vent open on tank.
 
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