Honda 50 power

[TAM]

I've seen MANY posts on troubles with Honda 50s, but looking for advice on what to check first. Engine idles fine. If I advance the throttle quickly it sputters and dies. If I advance slowly, it keeps running, but never reaches full rpm. I don't have a tach connected so I don't know exact rpms. 2007 bf50a. New fuel, old fuel hose. Getting ~11knts, last year got ~16. I don't want to go through a carb rebuild if I don't have to.

What have others found to be the real issue?

[ROAD Soldier]

Hate to tell you but it is your carberators in one form or another but not all is lost try these things:

First lubricate the carberator linkage.
Second take the drain screws out and squirt high quality carb cleaner up in them.
Third if that doesn't work take front intake off and squart carb cleaner in each carb.
Lastly take carbs off and take them apart. This not hard and there isn't a lot of small ball bearing in them like a Rochester Quad Carb for a car.
The bad thing is there are no carb rebuild kits for them you have to order each individual peice other then the packing that you can get in a kit. Marine parts are not as expensive as aircraft parts but are diffently more expensive than automobile parts for the same part. I rebuild all three of mine with $300.00 worth of parts. Next winter drain your carbs and preserve them with sea foam and will not have this problem.

[Retcoastie]

First, check that the throttle plates open all the way. You may need to lubricate the carburetor linkage or replace the throttle cable. Then, run a tank of fuel with sea foam in it.

[Just Nuisance]

Sounds like your high speed jets are clogged. I rebuilt mine during the winter. It was quite easy. There are five very small holes (Jets) at the top of your throtle body that flow fuel during high RPMs. If they are clogged your engine will stall as the RPMs increase. If carb cleaner in the fuel does not work. You should buy a shop manual off of ebay (cheap) and rebuild (clean) them. When I bought my boat last Sept I had this problem. Ethanol is a pain in the butt when it comes to carbs and the improper storage of an engine.

Good luck

MIke
Just Nuisance.

[Laika 26X]

FWIW...check the plugs.

Pull them, inspect them, smell 'em and taste ‘em! See that they are not cracked or damaged in any fashion.

Needless to say, my Honda 50 exhibited the same exact symptoms (you describe) as the ethanol "clogged carb" issue that we've been reading about since '05.

I replaced the fuel filter, fuel lines, cleaned and I scrubbed the tanks, and even I added an inline separator/filter, no go.

I added "SEAFOAM" Carb cleaner, still no go!

Then I brought in the "big guns", the "Certified" Honda Mechanic.

After having all three carbs rebuilt, one replaced at cost of $900+, still no go! (He tested it at the dock and it ran fine throughout the throttle range, after he left I got underway the symptoms returned!)

Finally after screaming on the phone, the "expert" Honda Marine Mechanic returned and found a broken plug in cylinder #3.

Boy I was angry, probably more at myself for not checking that. Regardless, I fought with the Mechanic to no avail, claiming I knew of the plug issue.
Why would I spend $900 if I knew the issue??

I also love how all the "Monday Night Quarterbacks" came out and said, "Dincha' check the plugs??" NO! I had naturally assumed...like they ALL said, that the carbs were clogged.
Why didn't someone tell me THAT along with all that ethanol advice???


Regardless, the point here is to check the plugs too. I’m not saying that IS the issue, but it cost’s nothing to do. You may just save yourself time and $$

Ed "How I could a spent that cash on Mods! "Tordahl
S/V LAIKA
USCG Auxiliary
Qualified Crew
Qualified Aids (Nav) Verifier
Qualified Instructor
NYS Qualified Instructor

[argonaut]

Actually since they're like $3 a piece I don't bother removing, testing and reinstalling them. I'd just replace them.
A plug can crack and arc internally and you'd never see it.

But since it's a HONDA my dollar still says one or more carbs are cheesed.


Happy with my Yammy
-argo

[ROAD Soldier]

argonaut is right, most if not all sparkplugs are made out of porcelain of some kind of ceramic material that can crack so microscopically you will not notice it. If you are ever at a Auto Parts store and you have the clerk get you some sparkplugs and he drops one or more do not get those plugs. I don't care if there in a box and only dropped 3 feet do not get them. However if it was a spark plug I think it would run rough at idle too. But just in case there is some weird fishing line theory at work here ( I still believe you Dave put the weapon down!) pay the cheap amount to replace the plugs if not just to do nothing more than eliminate the cheap fix as the solution.

[John McDonough]

While your buying spark plugs, for another $5.00 get a fuel filter. I believe the Honda 50 uses the same filter as a Honda Civic Auto. (somebody posted that info here a few years ago)

I had bad gas once, Motor was smoking bad when I started it cold. After it warmed up I would have trouble getting it to start. Repaced the old fuel an added lucas fuel conditioner to the next tankful and it was OK.

Every fall, the last time I use the engine, I pull off the fuel line and let the motor run until its out of gas. I also drain the carbs by unscrewing the small drain screw at the bottom of the carb.
A few years ago when I was unscrewing the fuel drain screw, I mistakenly turned the Air mixture screw out. I checked the other two carbs and placed the air mixture screw between the two settings. The following year when I replaced my plugs, I noticed that the plug was black and fouled at the carb I had messed with.

Good Luck.. keep us informed of your problem and solution.

[TAM]

Replaced fuel line and sprayed carbs with cleaner. Added fuel based cleaner. No real change. I installed a tach and it seems to get blocked around 3200rpm. I believe I read in other posts that that seems to be a magic number. Tried to change plugs but brought a 5/8 socket (new plugs are 5/8) but old plugs are 7/8. Runs well enough so I figure I'll wait until the end of the season to rebuild the carbs.

Is it worth trying seafoam?

Terry

[Retcoastie]

Yes, try the SeaFoam. It can only improve things. It will not harm anything and is cheap.

[capncarp]

There is alot of good advise here. I had the same problem with my 99, 25 Merc. One day when trying to figure it out I noticed that the plug wire on one cylinder was just long enough to reach the plug. Well, since I was rideing the ole Harley that day I robbed the plug wire off it and put it on the Merc. Problem solved. It never ran better. Apparently good enough contact by the shorter wire wasn't being made and she would stall at high or more abrupt RPM's. The mechcanic's didn't find that one either.
capncarp,
99

[Gypsy]

My Son who was a mechanic in the Army , is now a contractor with the Army was the first to turn me on to SeaFoam . He wholeheartly believes in the stuff.

I have turned off many a "check engine" light , with SeaFoam .

It won't hurt your engine , it will only improve it.

I had problems with the sparkplugs in my Honda as well . The engine was running rough , backfiring , would smooth out ,then get rough again. I was thinking it was carbs as well .
Turned out , the center elctrode in one of the plugs had come loose and would close the gap , shorting out the plug , then that cylinder would die, then the electrode would move again and it would come back to life .

I didn't discover this untill I decided to change the plugs just as a matter of "making sure" they wern't a problem.

[sbods]

As previously stated.... £ for £ changing the plugs is a worthy investment.

[Dave X2000 Jac]

Just throwing this out as another possibility...
I also have the Honda 50 on my 2000 Mac. I hadn't studied engine ("under the hood") very well when I purchased the unit, new.
It looked like I needed a fuel filter - I had yet to notice the one already attached, but hidden from view,
I installed a good fuel filter in the middle of the fuel line running from the tank to the motor.
99% of the time it sat in the well coiled with the line. A month or so later, on a day with little wind, the kids wanted to go for a boat ride.
I took them out, but we couldn't get much above an idle. I trailered the whole thing to a Honda Marine mechanic.
He did just about everything he could, and he still couldn't get it up to speed. Even though the inline filter I had installed wasn't discolored, I decided to replace it.
While loosening the clamps from the filter, I found a severe bend in the plastic tube running out of the filter to the motor. One of my "little angels" had stepped on the filter
when it was out of the well, bending the tube carrying fuel to the engine. A new fuel filter and I was back in business. Did the hard plastic hose running from your filter get bent?
Dave
p.s. I've been gone from this site for a while. On Heath's older page (second of three?) I was a more-consistent contributor. Two daughters in college out west - thousand miles or so away, wife working full time, my dad too old to go out for our annual trips to the North Channel has kept the Mac under tarps for four years. I recently retired after 37 years of teaching Junior High lab sciences. The polish for the Mac and the black paint for the trailer are yet to be purchased, but It won't be long before I will be here sharing other "dumb" things I can do to mess up a sailboat. However, sailing is still on the back burner. I have to get my brother up to the top of some Colorado 14ers this fall. If any of you will be near Handies, Redcloud, Sunshine, Torreys or Grays this mid-September, feel free to pitch a tent near ours (- then point me in the right direction to the top ).

[verena]

We have a 1999 Honda 50 on Webfoot and it was doing the exact thing you describe. We got the carbs done and now it runs like a champ.