95 honda 25 hp tiller misfire.

bigmeal

Cadet
Joined
Sep 23, 2008
Messages
8
Hey does anyone know what to do with a 95 honda 25 hp tiller outboard that has a misfire on # 2 cyl? I have switched up spark plugs to different cylinders, switched up coils, checked compression and made sure there was no broken valve springs. I do have a spark on #2 but it looks like a cold spark (orange looking spark, not blue). I did change up spark plug and the problem still persists on # 2 cyl. Could the problem be in the cpu? I don't think it is a carb problem as it was running great and all of the sudden picked up this misfire. It seems like when the engine works hard for longer than a half hour, it seems to turn a little sluggish. I would really appreciate some expert advise on this. Thanks
:confused::confused:
 

hondon

Lieutenant Commander
Joined
Jun 11, 2001
Messages
1,922
Re: 95 honda 25 hp tiller misfire.

To tell you the truth you have really narrowed this down to exactly a fuel problem.If you have ignition output ,compression, proper timing that you verified with that valve adjustment,Right?Exhaust , then all should be good.If you are still convinced you have ignition problems take a timeing light out and see for yourself.Or save a bunch of time and take a fuel sample out of the float bowls into a fuel safe container and let us know the results.
 

bigmeal

Cadet
Joined
Sep 23, 2008
Messages
8
Re: 95 honda 25 hp tiller misfire.

Thanks, I will give that a try. It was fresh fuel that I just put in, but maybe some water got in or something. What should I be looking for with this fuel sample that might have led me to this symptom? Thanks again for your help and I will let you know what I find.
 

hondon

Lieutenant Commander
Joined
Jun 11, 2001
Messages
1,922
Re: 95 honda 25 hp tiller misfire.

Drain each of those bowls into that container.I suggest something at least translucent if not transparent.Jars work great but are breakable so be carefull.The paint store has containers that work well without the breakage issue.Now that I've tried to make you a safe boy, take those samples.Any water,will be evident in the bottom of that container as well as any other crap you have just drained out.
 

walt-oxie1

Petty Officer 2nd Class
Joined
Aug 13, 2009
Messages
141
Re: 95 honda 25 hp tiller misfire.

This is a problem that I have on several of my Honda 3 cylinders. Commonly it is the bottom cylinder that has a miss. The problem is most likely a clog in the venturi tube in the carb. Remove the carb, remove the bowl, remove the big flat tip screw in the bottom of the carb body. This will expose the tube. The tube will need to be GENTLY pried out with either a flat tip or needle nose pliers through the end of the carb (I cannot remember if it is the choke opening side). Once the tube is out it needs to be cleaned out with a small piece of wire or torch tip cleaner. There are 2 small holes in the side of the tube and one end that get clogged. Work the wire through until you can see through the tube. Then spray with carb cleaner and reinspect. Once it is totally clear it is time to put it back together. The small holes in the tube go parallel to the choke shaft. Lube the o-ring on the tube with a little oil and GENTLY pry it back in place through the opening in the carb. Put everything back together in reverse order.

I have to do this to mine about once a month. Then again, I commercial fish and rack up a bunch more hours than most. Not to mention 12 gallons or more of gas every day.

Hope this helps.
 

bigmeal

Cadet
Joined
Sep 23, 2008
Messages
8
Re: 95 honda 25 hp tiller misfire.

I really appreciate all the advise I and I will certainly put it to use this weekend. I really want to get to the bottom of it and get out fishing again. I will let you guys know how it works out.
 

bigmeal

Cadet
Joined
Sep 23, 2008
Messages
8
Re: 95 honda 25 hp tiller misfire.

So guys, it did turn out to be a carb issue. My #2 carb had the needle valve clogged as walt-oxie1 had so helpfully suggested. I cleaned it and made sure as well that my fuel didn't contain water. It seemed clear and now that the needle valve is free of crap, the motor is like new again. Thanks once again for your guys help!!!:D:D:D:D
 
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