carburetor problem Honda BF 90

[T.R. Bauer]

Bob,

If I store my old Honda 45s they way you are supposed to they get a stuck float or two every spring. Unfortanately I have a lot of experience with you have going on. I know this is crazy, but I put Stabil in the tanks, don't drain anything, and squeeze the primer bulb every 2-3 weeks until they are firm again. I have never had a stuck float since adjusting my storage procedure.

My advise if soaking, tapping, and time hasn't worked, is to open the carb drain and give it a few blasts of compressed air. It has worked on mine before as a last ditch effort to avoid pulling the manifold. Sometimes running the trim up and down helps too......I feel your frustration here!

BTW, if I remember right, the 90 is very close to the 45s on the carb setup. It only takes a few minutes to get the entire manifold off with all the carbs. It really isn't to hard. Getting gaskets on the parts store shelf might be harder - at least it is for me......Good luck and I hope you fix it soon!

[thataway]

Yes, from reading and looking at the diagrams/photos, the same basic carb is used from the 25 on up thru the 150. The linkages are a bit different. Re-sync and getting the linkages correctly aligned are probably the most difficult part of removing the manifold, air filter. Just time in a busy schedule, and the boss wants to do the final clean and pack the boat, so we can go break some ice in Lake Superior…..

Alaska and Florida do both have their challenges with fuel. Unfortunately part of the year the C Dory is left for 3 months where I could not squeeze the primer bulb--but that is a technique well worth remembering. I had also considered the compressed air--The carburetor cleaner I am using has a pretty good pressure in it, and I seal the drain tube around the output, so the float gets a good blast. I probably would have fired up the compressor, and tried that, but…..

This morning, I gave one last good blow--plastic hammer to a piece of plastic held against the carb. Drained the solution which soaked the bowl thru the night, and squeezed the bulb--it came tight, with a couple of squeezes-- [b]no more leak!

The engine fired up after a few cranks, and low speed idle is a little rough. I have filled the other carbs with cleaner, and have carb cleaner in the fuel, so I 'll see if that takes care of the rough idle. It does not stall on shifting, so I suspect with some fuel, it will smooth out.

Thank all of you for the comments and suggestion, and hopefully this discussion will help someone else.

[T.R. Bauer]

I am so glad to hear that. When mine used to do that, an overnight soak would often free them up. It's good you didn't have to tear it apart. After all that carb cleaner runs through the carb, and you actually have pure gas in the float bowls, you can turn the idle mixture adjustments to smooth out the idle. Sometimes a little piece of crud gets stuck on the needle part of the screw and just a little turn lets it pass on by. If they are anything like mine, just a quarter to half turn or so does the trick. Then, put it right back where it was when the idle smooths out. If this doesn't work you might have some deposits in/on the stupid emulsion tube, or even a crack - which is very common. However, the idle mixture adjustment screw just might do the trick and I'd screw (pun intended) with those first. This will not mess up you carb synchronization.

[thataway]

Thanks---great idea, and I'll get to that! It was interesting to see when I first ran new gas thru the carb that was sticking--I had a little crud in it. After soaking all of the bowls in carb cleaner, and then draining, flushing with pure gas, again, each carb had a little curb. Darn Calif. for lack of sanity and not allowing pure gas for outboards…. (I love to blame California for all sorts of woes--I was 5th generation--but not the first in my line to leave. My kids love to defend California, and tell me why I should have stayed and paid their taxes! )

[katkt]

I just pulled the manifold, and opened the carbs to replace the idle tubes, on one of my motors. It really wasn't a bad job. It looks far worse then it is. The choke and throttle linkage just pops off of the carbs(mine were ball socket affairs). You don't have to mess with anything that needs adjusting.

Pop the two linkage bars offThrottle and choke)
Disconnect the fuel lines at the opposite ends from the carbs.
Loosen the nuts on the bracket that holds the linkage in the bracket, and slip them out, and then ease the barrels out of the throttle wheel(I'm assuming this is similar to my 90's).
I had two bolts that held the throttle linkage bracket on the motor. I had to remove the bracket to get the manifold off.
With everything out of the way, remove the bolts(I had two nuts on studs as well).
Remove the manifold/carbs/air box as a unit.
Remove the airbox from the carbs.
Repair carb(s).
Clean gasket surfaces, and reinstall new gaskets.
Replace the intake assembly.
Reconnect throttle linkage, bracket, choike etc., in reverse order.
Reconnect fuel lines.

It's not that bad of a job. Don't tinker with any adjustment, and you can put it right back together again. If it was running good before, then you shouldn't have to do anything but RandR the manifold and carbs.
The whole thing took me about 3 or 4 hours from start to finish.
I had to replace the intake to head manifold gasket, and the gasket between the carbs and the air intake box.

[hardee]

Sounds like you are well on the way to a better day Bob. Hope it continues.

I'm not a mechanic so this is what I do, per instructions from my (Yamaha) mechanic.
1. Every tank, every time, Marine (blue) Stabil, and Startron Enzyme Fuel Treatment. Both at the maintenance levels.
2. End of Season. On the last tank fill, double up on the dose of both then add in the full tank of new fuel. (I fill it really way up to the top.)
3. Run the engines for at least a half hour to an hour to thoroughly get the new mix into the system.
4. Park the boat. No draining or adding anything. (Oil changes excepted.)
5. Keep the batteries charged.
6. Come spring, on a fully charged battery, pump the bulbs till firm and ...
7. Start the engines. Go run that first tank through to at least half down.
8. Add new gas with the double mix. Then from there on go back to the maintenance mix on every fill.

Has worked well for my Yami's, with a layover of 8 months one year. Started and run without a problem. Honda may be different. And I have been doing this with 10% E (eeek) gas every year.



Harvey
SleepyC

[T.R. Bauer]

They really are not that bad I agree. But, they do have the appearance of nightmare written all over them. Hopefully they behave for a long time.

[thataway]

Hardee, are your yamaha's fuel injected or carbs? I think that the heat causes much more rapid detiorration of the fuel, and is more likely to have the carbs gum up.

My 140 Suzuki is injected: I avoid ethanol in the gas. I put Stabil and Starton--always fires back up 4 to 6 months later.

In the case of the Honda, 90 the fuel was shot. I would not run it in a lawn tractor.

Katjt--thanks for the description--hopefully I will not have to do this in the Wild's of Canada…So far the engine seems to be fine after cleaning the other carbs.

[katkt]

I hope you got it squared away. I had one motor, that was running rough, and wouldn't throttle up properly. If you'd force it, it would die. I was able to cheat it into the upper RPMS, and it ran great up there, just couldn't get over the throttle hump from the pilot circuit to the main without coaxing. Good to go now.
If you do have to get into it, Bob, I'll PM you my phone number and if you want somebody to look on and offer encouragement, I'll make some time. I was worried about adjustments also, but the only thing I used a screwdriver on, was the bowl screws, and the jets. I blasted everything out, while I had them apart.
The bike forum I'm on, has a lot of sticking float valves(needle and seats) this time of year. Usually if you can get them to stop leaking, and they run, they'll clean up.

[hardee]

My Yamaha's are carbed, 40's, twins. I don't always have options to get E-free gas.

Harvey
SleepyC

[thataway]

'The final post on this saga. We have been talking about launching the boat--but it has been too hot (close to 100 degrees--and the reason we usually go North this time of year). This morning we had to get up at 5:30 so a friend could work on our attic fan, when the temperature was less than 120 degrees in the attic! By 8:30 he had replaced the fan motor and we were back in business--great time to launch the boat.

The engine fired right up. came back across the bay at 18 knots, happy as can be, took the boat up to 25 knots, no problem, Idles smooth. So letting the carb cleaner sit in the jets did its job

Also got a chance to try out the Garmin 1040xs and 740S. Both transducers work and hold the bottom well at speed. The Down scan/chirp is great! Radar works--so all projects are done and checked off!

Thanks to those who helped and made suggestions!

[Sunbeam]

[Wayne McCown]

What "carb cleaner" did you use/do you recommend? Is there a difference between the carb cleaner you would use in an auto, and what should be used in an OB motor?

[thataway]

O used "Gum Out" Gum out is 60 to 100% acetone, 5 to 10% propane (propellant), 1-5% Methyl Ethyl Ketone, and 1-5% petroleum distillates. I used the spray can, because I could spray the solvent retrograde into the carburetor drain tubing, and fill the bowl with the cleaner. Yes, this is the same I have used in generators, cars and outboards in the past. I have put Lucas fuel treatment into the new, non ethanol containing, fuel (after pumping out all of the old fuel I could.)

[Wayne McCown]

Thanks!!