unblocking fuel system on johnson 2hp outboard

PaulR

PaulR

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our poor little outboard lives all season in a cockpit locker and very rarely comes out (last used summer cruise in august) and come winter comes out - is lovingly run in and flushed through with fresh water, drained and lives in the attic for the winter,
last winter for the first time- it wouldn't start for the winter flush through and I eventually gave up and took it to outboard bod who fixed it - saying fuel system was clogged and thereafter if was fine when used in the summer- this winter once again no life - spark big and healthy so assume that must be fuel again - any one know how to clear jets etc on diy basis and any idea why (if that is what it is) is should happen again so soon?

thanks
 
You do not say what year or model number so impossble for anyone to give specific advice. However the 2hp carb I have looked at is relatively simple and it should be possible with reasonable care to remove the jet assembly and clean it. No poking with wires though! Take care not to lose any small bits or damage any gaskets or O rings

Do not overlook the posibility that the float or its associated needle valve are sticking so preventing fuel getting into the carb. If there is a drain plug on the bowl removing that will tell if there is fuel in there or not. It would be sensible to check this first before going any further.

You willl find parts diagrams on The BRP website which may be helpful in identifying what is what. You will need to enter the year, HP and maybe model number as well as selecting Johnson.
I would clean out the fuel tank as a precautionary measure and take care to only use clean fuel in future. It is possible to store fuel in the correct conditions but with the small amounts you will have for a small engine it is probably more sensible not to. It is a good practice to turn the fuel off and allow the carb to run dry before stowing the engine away if you can. That will prevent gum deposits forming and blocking the jet.
 
Also get an in-line filter from your friendly local motor factor. Only cost buttons. The standard filters on engines I've had dealings with have been rubbish, and let all sorts through.

Safe sailing

Sparkie
 
There should be a filter of sorts in the tank outlet but not so fine what as you are suggesting. There may not be room to fit an additional filter as the pipe between tank and carb is fairly short. With good care when handling fuel an extra filter should not be necessary. Only once on 30 years have I had trouble with a fouled up carb (provided you dont count the time water got in somehow) and that was the only time I used fuel stored from the previous year without filtering it.

PS my earlier comments were based on recent models, 2000 plus or minus a few years.
Earlier models eg from the early 1980s had a more complex carb with separate fast and slow running jets and separate adjustments. If the carb in question has any adjustments note their settings before dismantling
 
Get a can of carb cleaner from your local car DIY/Halfords, It gets into all the corners and dissolves petrol residues. Petrol if left to evaporate leaves a sticky brown residue that can be difficult to remove without a powerful solvent.
 
If you do want to fit an in line filter pop into Your local Motorbike shop/menders.
They should have "small" ones.
Plus carb cleaning stuff.
However as VicS points out there aint mutch room to play with.
Your bike shop man will also be clued up on Carb cleaning, especially a comparetively simple jobby on Your outboard.
Probably have an air line with a nice jet to blow the muck away!
 
FWIW, I have an old yamaha 4hp 2stroke o/b, I warmed the engine, poured half a bottle of "Wynns" (sp?) carburetor cleaner into the tank and let the engine burn it all... it did it with a bit more smoke than usual (and it took a very long time, surely more than one hour)
after that, the engine started and ran much smoother (keeping idle, higher revs, less need of choke for starting, etc), it s maybe just an impression but I think I ll do the same treatment again every year

/forums/images/graemlins/smile.gif
 
If you want or need to identify the exact year you can do so from the model number (not serial number) stamped on a plate on the mounting bracket. It will be something like J2RCNE where J=Johnson, 2=2hp, R=ropestart. C & N are the year letters where I=1, N=2,T=3, R=4, O=5, D=6, U=7, C=8, E=9 and S=0. Other letters eg the final E are not significant. The model number should also be stamped on a core plug on the engine itself.

Yours will have a carb with separate high and low speed mixture adjustment screws. The one at the bottom of the float chamber is the high speed one while the one in the top cover is the low speed one. If you remove them screw each one down fully first noting how many turns it goes so that on reassembly you can set them in the original positions. You should find that they are about 1½ turns open.
 
still trying but so far no success- fuel definitely gets through to float chamber when fuel tap turned on - have removed both jets and washed them and now leaving them and carb to soak for day or 2 in cleaner then will try again - many thanks for help so far - mine is BJ2RCOC which I now understands means johnson 2hp rope started and this year celebtrated it's 21'st !!

determined to keep it going so will keep trying,

thanks all
 
That has a similar carb to my 6hp, except that has a fixed high speed jet. I have never had to touch the carb so why yours is so problematical is a bit of a mystery.

You may find you have to clean the jets and passages with a wire if soaking does not do the trick but use a soft copper wire with caution to avoid damage. I had to do that with another one which had got water in it.

R U absolutely certain that the float chamber is filling to the correct sort of level?
 
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