How do I do this?

1996 Evinrude 25 HP

How do I, or do you even adjust the timing on this motor?

New to the whole two-stroke outboard thing so I don't have a clue. Just wondering if it is something
that should be checked as a new to me, older motor.

Thanks!

Timing usually doesn't change.You'd be better to check the water pump impeller & gear lube in the lower.

FWIW with owning or running > 50 OBs in my life, I have only ever had to check/confirm the timing on one, and that a big V6 after a complete power head rebuild.

I had to adjust the timing on my 1994 Johnson 50/35 after my buddy and I completely rebuilt it. It involves using a timing light connected to the #1 spark lead and running the engine at WOT in forward gear. You point the timing light on the flywheel timing "grid" and then adjust the length of the spark control rod up or down to advance/retard timing as needed. Your manual will tell you where it should be at. IIRC, mine didn't need a lot of adjustment but it definitely helped. We also fine tuned the carburetor linkage and idle adjustment all at the same time.

Alright, well I am going to say then that my timing is OK as the motor has never been torn into. The reason I was asking is because at idle, in gear, I get a "cough" or a "sneeze" where it will almost shut down for a split second but kick back on and is fine. Doesn't do it in neutral, so only under a slight load. Idles all day in neutral, runs perfect when on the throttle and doesn't miss a beat! Any thoughts?

Kustrud said:

Alright, well I am going to say then that my timing is OK as the motor has never been torn into. The reason I was asking is because at idle, in gear, I get a "cough" or a "sneeze" where it will almost shut down for a split second but kick back on and is fine. Doesn't do it in neutral, so only under a slight load. Idles all day in neutral, runs perfect when on the throttle and doesn't miss a beat! Any thoughts?

Click to expand...

Sounds like a carb adjustment is all that's needed. Try a quarter turn CCW on the slow speed needle while idling on a boat in gear and see if it improves.

-jasper

Yes, sounds like a lean sneeze. ONLY do this in the water - not in a barrel or on muffs. After setting it, take it out for a high speed spin - if she coughs or sneezes again, it's needs another setting.

FWIW, from where initially set, I always COUNT the # of turns IN (and NOT forcibly tight so as to damage the seat). Write it down!

Now turn it OUT and back to the setting and work from there. Ideally you want the smoothest idle at the highest revs without bogging, spitting, coughing or sneezing. If she was running OK, I turn it IN a turn or so - to where she stumbles - and then work my way back OUT by 1/4-turn increments only. Always letting her run for a minute or two at each setting.

If you get "lost" ... since you wrote it down, you can go back to where she once was set :wink: ... and at least running.

Alright good deal, thanks! I turned it CCW about 1/3 of a turn in the garage and took it back out and it seemed worse before posting this, so I just turned it back. But maybe I just need to do it on the water an keep going until it stops coughing?? What happens or how do I know if I have turned it too far CCW?

You need an OB in the water for adequate backpressure. And turning 'too far' in either direction causes it to either stumbles or starts to die (too lean, by turning IN) or run rough & shakes (too rich, by turning OUT).

I also like tuning OBs "on the water" as a high speed test run, then slowing right down to idle/headway speeds can tell you if it is still not optimally set.

Usually you don't have to fool with timing but sometimes you have to. It is rare though

Yeah it's gotta be a lean idle. I'll play with it next time out and let ya know. Thanks!