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Honda 25 4stroke issues

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nate0311

New member
HI All Im hoping for some insight on an issue I'm having with an older outboard I have. its a 2001 honda 25hp 4stroke that I just had 3 brand new carburetors installed about a year ago. After that point I did not use the boat much besides to run at idle in the driveway. I had no issues running in idle and last week I took it out and ran it in the water for a few hours. At one point during the trip I was about 3/4 throttle and I felt a give or pop in the throttle and had to bring it back to neutral. After that point when I started engine I would have to run it at full choke for it to run it neutral and then quickly put it into gear for it to run. after that it would run fine in gear but not neutral. I hauled the boat out and adjusted the idle screw 2 turns and then engine now idles well but when I put it in gear it dies. I have tried leaving it in neutral and running for about 10 min then putting in gear but it immediately dies. I tried backing off the idle screw but then the neutral craps out.

sorry for the long winded story

any help would be greatly appreciated.

Nate
 
If you the motor runs with the idle mixture screws turned out 2 turns more than the standard 2 3/4 turns out, then you probably have debris in one or more carburetors. It is very possible that the idle fuel passage or idle air jet is clogged.

Typically, it means a carb job....but you can try one thing....and you might get lucky

Drain all the carburetors and take out the drain screws.
Remove the idle mixture screws and springs.
Take some brake kleen or similar solvent (carb cleaner as a last resort...since it is more caustic) and stick the straw into the idle mixture screw hole and give it a few good shots.

If you have compressed air available, give it a couple of shots of air. Do not hold the air tip right up against the carburetor...you could blow out the little silver plugs on the side and top of the carburetor. If you lose them, you can not buy them from Honda.

If you do not have compressed air, you can use a can of compressed air that you use to clean your computer.

Then do the whole process over again....spray solvent......shoot with air.

What this does is potentially clean out the idle air and fuel passage.

Once you do that, squeeze your fuel bulb some to flush debris out of the carb, if any got blown into the bowl. Any debris that was blown out of the air jet would go into the intake muffler. The debris is so small, you probably would not be able to see it anyway.



After the carbs are flushed, put all screws back in....set idle mixture screws to 2 3/4 turns and start your engine and see if you got lucky.

It may be hard to start at first due to the extra solvent in the carbs.

Most of the time this does not work, but sometimes it does if the debris is very small and not lodged in place.

If it works....go buy a lottery ticket.

Good luck!

Mike
 
Mike's trick just MIGHT work for YOU. The reason I say that is that these carburetors are new. So, if this has a chance of working for ANYONE, it would for newer carbs.

The reason I chimed in however is to speak more about how NOT to have it happen again. You didn't say but I'm guessing that while this outboard typically just sat in the driveway for the last year....you probably never DRAINED the carbs.

This sort of "contamination" might not EVER happen if the carbs are ROUTINELY drained dry if the outboard is to sit for any time longer than a few days. Honda carbs do NOT do well when left to sit for more than a week with ANY fuel in them. It is best to run the engine with the fuel line disconnected until it quits...pull the kill key.... and THEN open the drain screws on all three carbs to remove what is left in the float chambers.

Also, to add to Mike's suggestion.....you may want to do EVERYTHING that he suggests....plus....pull the intake "muffler plate" (item #37 in the link below) and insert the cleaner straw into the drilled passages, at the front of each carb, that are above and to the side of the BIG Venturi hole or "carburetor throat". Just a couple of "blasts" from the straw and then a LIGHT rinse with compressed air, as Mike described, will suffice.

Note that the muffler has a pretty large gasket that it mounts on. This gasket is prone to tearing during removal so you may need to patch it or replace it. In addition to that, the bolts that secure the muffler also secure the carbs to the intake manifold. I use "studs" that I make from bolts purchased at the hardware store to keep the carbs in place when I don't want to completely remove them. Yours may want to "fall off" because everything is so new and not "baked on". So, if you want to try this cleaning step, you need to consider that as well.

http://www.boats.net/parts/search/Honda/Outboard Engine/2001/BF25A1 SHSA/CARBURETOR/parts.html

If this works it will save you a BUNCH of disassembly and cleaning but after that...

....DRAIN THOSE CARBS!

But...most of all....

GOOD LUCK!
 
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