Honda is sputtering

Tom turkey

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Sep 14, 2014
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15
I have a 98 honda 40 hp four stroke with carbs. It had been sitting for a few years, got new gas in it and all but did smell old gas so some must have been in there and pushed thru.. I can get it running under choke with throttle but its sputters.. I think its just two cylinders firing, its purrs for a few seconds with carb cleaner sprayed in...as soon as you take off the choke it dies out.. Could the old gas have the fuel filter buggered or buggered the spark plugs? It seems like its so close to taking off... I was going to get a new filter and plugs... Any chance that will do anything? Any other thoughts?
 

alldodge

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Mar 8, 2009
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I have a 98 honda 40 hp four stroke with carbs. It had been sitting for a few years, got new gas in it and all but did smell old gas so some must have been in there and pushed thru.. I can get it running under choke with throttle but its sputters.. I think its just two cylinders firing, its purrs for a few seconds with carb cleaner sprayed in...as soon as you take off the choke it dies out.. Could the old gas have the fuel filter buggered or buggered the spark plugs? It seems like its so close to taking off... I was going to get a new filter and plugs... Any chance that will do anything? Any other thoughts?

:welcome: to iboats

Not a Honda dude but if you added new gas to old gas there will continue to be an issue until it is all gone. If it was just the fuel left in the carbs then that would be OK. From the sounds of your issue you have a fuel supply issue. I would suggest doing a compression test to determine if the engine is sound. If compression checks out then pull the carbs and clean them. If old gas sat in them it leaves behind crud which will clog them up. Best way to store any engine for a long period, is disconnect the fuel supply and let them run until the engine dies.
 

midcarolina

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Jul 16, 2013
Messages
631
Pull the carbs disassemble and clean every nook and cranny.............Sounds like at a minimum the slow speed circuit is clogged up.
 

Tom turkey

Cadet
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Sep 14, 2014
Messages
15
And they need sync when reassembled? I cant do that part, should i still do the carbs or just have it serviced?
 

midcarolina

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Jul 16, 2013
Messages
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Here is a link to a video of a guy working on carbs of a Honda 30, Maybe it will be a little helpful........... The guy is not a mechanic and managed to get the job done.
 

steelespike

Supreme Mariner
Joined
Apr 26, 2002
Messages
19,069
Speaking generically;
Symtoms are classic fuel supply problem rebuild the carbs.Very likely one or more jets or passages are plugged.
If your mechanically inclined you should be able to do the job.Most brands lync and sync are usually pretty straight forward.
You will need a factory service manual.
 

isaksp00

Petty Officer 1st Class
Joined
Jul 14, 2010
Messages
225
If you are going to take the carbs out, I would also dip them in the stronger carb dip - that comes in the gallon cans. I find that the carb spray doesn't do a good job in the tiny passages in the carb body. Just make sure you dip only the metal parts.
 
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