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Johnson 8hp

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the_flying_scotsman

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"Hi i have just got a J8BAESR

"Hi i have just got a J8BAESR 8hp johnson. It wont idle and will only start with choke and a lot of throttle fiddling. I have done a carb kit and replaced the spark plugs, new fuel mix and cleaned everything . Hoever it still acts the same.when it does rev it is strong and free. i have tried to get it to idle using the choke but cant get it. i set the slow idle screw at 1.5 turns out as this was where it was when i took it out. I have to fix the stop switch which was broken off but it wouldnt even fire if this was concerned right ? when it dies it feels like it is choking !
any help is good help"
 
"correct about the stop switch

"correct about the stop switch...have u put new plugs in it?...u need to try to determine,..if it is dying ,due to ..over-fueling--flooding,...or running too lean.....
compression/spark tests,..are always first..
is this eng new to u,..or,have u had it many yrs?"
 
"(Carburetor Adjustment -

"(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note 1: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

Note 2: If the engine should be a three (3) cylinder engine with three (3) carburetors, start the adjustment sequence with the center carburetor.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay store at:

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
"I just got the engine from a

"I just got the engine from a friend. Who didnt seem to know much about it. I have changed the plugs,and the compression / spark is good. It does fire and try to run but cant get it to idle seems to me to be due to fuel prob. I guess as you said too lean or too rich . how do i test for these . Is it possible that the fuel bulb could give a problem , I pumps up but doesnt get as firm as others ive had."
 
Provided the fuel bulb fills t

Provided the fuel bulb fills the carb bowl it should be Ok. Some seem to feel firmer than others. If there is some air in there it wont feel as firm as it will if you get all the air out. (other problem sometimes is air leaking in to the fuel line but then it'll run for a few minutes then die as the carb bowl runs empty. Pumping the bulb will keep it going though)

Your carb is one with a plastic top?? There has been problems with those cracking and have been replaced with modified versions IIRC. Worth a check perhaps. JWB or Joe will know the details if that applies to your engine.

Joes adjustment instructions apply to carbs where the adustment screw is on the front. IIRC the initial setting for those with the idle adjust screw is on the side of the top cover is less than 1.5 turns. ¾ ??. worth a fiddle.

If the carb idle jet is dirty it should be possible to get it to run by playing the choke control.

Flooding due to float valve not closing properly ???. Try filling the bowl with the bulb then disconnecting the fuel line. It should run for a while on what's in the bowl.
 
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