# Honda 9.9 4 stroke carburator problems



## TSOJOURNER (Dec 16, 1999)

About a month ago I bought a 1988 Catalina 22 that came with a 1999 Honda BF9.9 (4 stroke) outboard. The folks that sold the boat told me they hadn't used it but twice in the past year (S. Florida) so when I arrived to "drive it home" I topped off the 1/3 full gas tank with fresh gas and happily headed out. About 15 minutes from their dock I increased the rpms but almost immediately the engine died. It started easily on the second pull (battery was flat of course) and maybe after 10 minutes of slow cruise I increased the rpms again and again the engine died. So I figured the engine was trying to tell me something and for the remainder of the 2 1/2 hour trip I left the throttle at slow cruise. The next day (after charging the battery) I started the motor easily with the choke out but after 10 seconds the rpms began to decrease and at 30 seconds or so the engine quit and wouldn't restart for 3-4 hours, neither with the choke on nor off. Then it started again only to the repeat the same exact sequence. I also noted that if I tried to lean it out then it quit sooner. I talked to some of the people on this board and they were very helpful...following their advice I checked the gastank air vent (ok), the fuel line to the fuel pump (ok), the fuel filters (ok), the spark plugs (black but dry) and I bled the carburater sediment bowl by loosening the screw to find a good amount of gas both before and after running. I was hoping that the diagnosis offered by several senior members (clogged carburator) was wrong and that their advice (to clean the carburator) was unnecessary but I am afraid they were dead on so I ordered the Selog mechanics manual for this Honda and when it arrives I will (gulp) attempt the job. I read with interest the suggestion that I strip the carburator of heat sensitive parts and simmer it on the stove in a pan of water for an hour thereby avoiding disassembly but thought I'd consult you senior sailors out there for your advice once more. Thanks again to the senior members who generously responded to my "out of gas" note.
ewjili


----------



## hellosailor (Apr 11, 2006)

Cooking the carb is like baking enamel paint: It may just do a nice job of setting the varnish in place.<G>

Ask yourself, do you want to start off with "maybe" shortcuts, or with a reliable engine in "known good" factory condition?

If you have a work area reserved for the job, and work slowly, taking notes or digipix and spreading the parts out in the sequence they need to be re-assembled in, this is a slow job but not a hard one. There's really no way to get into passages to make SURE they are clean, except with needles and tiny brushes and the like. And, a good soaking with a high end solvent is the only thing that will dissolve the "it's varnish, not a water-based paint!" deposits.<G> Laying parts out on an old terrycloth towel helps--they can't bounce or roll on that.

You're right to be suspicious of it.


----------



## tigerregis (Nov 24, 2006)

Not a mechanic but, worked at a Honda dealer. My boss, 38 years in the business told me 90% of problems was dirty carbs. Buy a can of carb cleaner and use the WHOLE can, This worked for most of the walk in "can you help me" guys. The needle advice is correct but at 4 bucks a can, start there IMHO


----------



## Newport41 (Jun 30, 2006)

I used to be a small engine mechanic. I'd try to spray some carb cleaner through the air intake after removing the air filter. Spray in short bursts or the motor will die. However this is a band-aid solution. You will have to clean the carb properly but it's not a big deal. Order a carb kit from the honda dealer. All you have to do is unscrew the screws, keep all the parts diagramed so you can put it back together(egg cartons are useful), clean with a can of carb cleaner, install the new rubber bits (that's the carb kit) and put it back together. And put fresh fuel it it. You can figure it out. And if not......well, then refer to that manual that you ordered. Good luck. It's not really a big job at all.


----------



## feetup (Sep 19, 2006)

*Honda carb.*

There seems to be a nasty circle brewing the last few years. 
Virtually all gasoline in the U.S. and much of it elsewhere now has ethenol added as an oxygenator/ anti knock additive. This was discussed at length in a recent thread. One thing that was not touched on there was the effect that the hydroscopic nature of ethenol has on the aluminum/magnesium alloy carburettor body and sometimes the float bowl of many outboards. If the fuel is allowed to collect moisture, and if this moisture is allowed to sit in an alluminum/magnesium alloy carburettor body the resultant oxide is a white powder that is pretty much resistant to any cleaners or petroleum solvents.
Being a metalic oxide it can only be reduced or removed by acidic disolution (an absolute no-no around magnesium) or by mechanical means.
If you dissasemble your carb and find white powder or coating scrape and brush to loosen it and blow with compressed air. Do not get agressive with anything hard in jets or passageways as jets are precision and scratches or gouges will affect them more than you would think. You could also remove all plastic and rubber and soak in a Carb cleaner THAT YOU ARE SURE IS SAFE FOR ALLOYS CONTAINING MAGNESIUM. I am not sure that the Honda carb contains magnesium but most small engine parts do. You could also remove the carb and have a Honda service center clean ot for you.
Now clean your fuel tank and fuel lines, and don't leave fuel in it for any length of time. 
Also, when the season is over go to your outboard or motorcycle dealer and buy a can of 'fogging oil' (I said Fogging) and use as per directions to winterize your motor.


----------



## resdog (Mar 29, 2006)

feetup is right on the money. Dump the old gas out of the tank. It's easier to buy a new tank and fuel line/fittings than to try and clean them out. Take the engine to your local Honda Marine dealer or a good independant shop and have it cleaned up and serviced. Chances are that after you attempt to rebuild the carb yourself, its not going to work correctly and you're going to end up at the dealer or a repair shop anyway.

I've always disconnected the fuel line from the engine after coming in to the marina and let it run till it quits. I've never had problems with varnished fuel, although this has always been with 2-strokes.


----------



## hellosailor (Apr 11, 2006)

"Chances are that after you attempt to rebuild the carb yourself, its not going to work correctly" "a good independant shop "

What planet do you come from? Finding a GOOD shop, independent or dealer, that will do a GOOD carb overhaul on any engine for less than a fortune, is a pretty good trick.

OTOH, rebuilding a carb doesn't require a lot of skill or practice, the rebuild kits usually include blowup diagrams and all you need is some time and patience to do a rebuild. Which will usually outperform what the average shop has done, simply because the average shop is rushing the job and thinks "Close enough" is a good way to work.

But if you know a careful shop that doesn't charge a fortune, please, do recommend them online, it would be worth SHIPPING to them.


----------



## resdog (Mar 29, 2006)

Hellosailor, it's so refreshing to know that there are still a few renaissance men such as yourself out there that are able to fix their own carburators. It is unfortunate that you have been unable to find a good repair shop - dealer or independent. They're out there. It takes a little leg work and asking for recommendations from your fellow sailors.


----------



## hellosailor (Apr 11, 2006)

Resdog, over the years I've heard many folks (not just in my area) asking/posting "Where's a good outboard shop?" and not get answers. Seems like since comic book went up from a nickel and kids stopped reading "Make money from home fixing outboard and mower engines!" ads, everyone has gone out of business. Or, they're so busy they don't really care when your engine gets done, much less how.

Not a unique marine problem though, even with cars I learned to overhaul my own carb after asking *dealers* (not as a stranger) for a referral and finding none of them could recommend one of those, either. Watchmakers are a dying breed, everyone else thinks "comebacks" are normal. Sad state of affairs, maybe it's better in the boonies.


----------



## sailingdog (Mar 19, 2006)

Unfortunately, a lot more has become disposable, as opposed to repairable. The cost of repairing a lot of goods today, like DVD players, TVs, and such is actually often higher than merely replacing them. 

The skills and tools required to overhaul a carburetor are not all that specialized, and it is well worth learning to do, especially if you plan on cruising in foreign areas, where such skills and parts may be even more difficult to find. That said, in less "civilized" areas of the world, repair shops are often easier to find, as the need for repairing, rather than replacing is much higher.


----------



## feetup (Sep 19, 2006)

*Carbs and stuff*

I can understand the frustration in dealing with outboard repairs etc.

I don't know about many areas but where I live there are always adult education networks every fall that have classes on everything from jazz dance to basket weaving and sometimes they have courses on small engine repair. Usually they happen at night at the local high school. I'm sure you would be a little hard pressed to find one on advanced geophysics but some of them are well worth the money.(usually quite inexpensive) 
A carburetter isn't really that complex, you are not disassembling the entire factory, just a small part of it. Many good repair manuals exist, usually with good graphics. The factory manuals while usually considerably more expensive are usually better. They go on the premise that you know something about mechanical things but you don't have to bluff anyone but yourself. 
The old method that tradesmen use when dissasembling something unfamiliar is the onestep forward, onestep back routine. That is take one piece off then put it back on to be sure you understand how it goes on. Then take it off again and set it on a clean cloth spread out on a place that will not be disturbed. Place each piece in the approximate order that it occupies on the carb. If there are adjustable needles, gently turn them in 1/4 turn at a time and count till they stop, then write it down! Make sketches of things.
Whatever it takes. It's just not that hard. The people that made it aren't any smarter than you are, and they don't have any magic tricks.
One point though, with screwdrivers, especially slotted and Phillips styles if you use an old well used screwdriver you WILL damage the screw. The steel used in common small engine screws is of a fairly soft alloy, both for cost and for ductility and the loads imposed on the tiny areas where the screwdriver and screw meet are enormous. You should get three screwdrivers in each type of three different sizes and baby them. They don't have to be Snap-on but don't be cheap either. 
One final note: before you attempt to remove any fastener from a marine engine give it a smart strike on the head with a small brass or aluminum drift and a hammer at a small angle to it's centerline. Sort of like dealing with a teenager, only they won't let you give them a good smack "upside the head" any more. This will usually fracture the oxides that form between the threads and give you a better chance of removing it without problems. It is quite amaizing how well this works. You can smack it fairly hard, just don't break the casting.
OK, THIS is the final note. ALWAYS lubricate, or anti-seize or locktite the threads on ALL fasteners. There is a whole thread waiting on the relative merits of anti seize of different types but at least oil the threads.

Feetup


----------



## hellosailor (Apr 11, 2006)

Priceless, feetup.


----------



## mike dryver (May 13, 2006)

ewjilli if you are near or can get to a NAPA store ask if they have their carb cleaner soaker in a can (1 gal) unforunately but this stuff works unbelievably well, and will not hurt the metal. just make sure there are no o-rings left in the body as they will usaully swell from emersion. you just soak for 1/2 to an 1 hr. flush with water let dry or blow dry and put it back together. after you kust pour the cleaner back in the can for next time. i've used this stuff for about 15 yrs. it completely cleans the metal surface of all and any fuel or oil/grease residue. 
regards mike


----------



## Valiente (Jun 16, 2006)

I have the exact same engine and the exact same issue, only I was powering a Zodiac C310 RIB when the Honda BF100 died, started, died, started.

Then I was glad of the oars.

I got the Seloc/Clymer guide and with a rebuild kit and a brightly lit and clean work area, I can't see this being too hard. The tapping with a drift advice is good...I had forgotten that old trick. I rebuilt my simpler Bendix carb on my Atomic 4 with little trouble. Just take your time and have a free hand with the goo cutting fluid. I plan on doing this job over the winter.


----------

