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89b 25hp Johnson CarbTiming issue

S

skylberg

New member
"My friend just bought a 89&#3

"My friend just bought a 89' 25hp Johnson electric start outboard. We hooked it up to a battery and fuel tank, replaced the spark plugs and gave it a crank. Initally fuel was running out of the carb vent (Stuck Float) but the engine would fire right up if you hit it w/a squirt of starting fluid. We removed the carb (after removing the starter to gain access to one of the nuts). Just as suspected the carb bowl was sludged up and the float was stuck. We cleaned it out and re-installed it and the starter. The fuel leak was stopped but now the motor will not do anything but backfire. We did not mess with the flywheel or timing. We put all of the wires and linkage back like we found it. Does anyone have any ideas? I have always done my own work on small engines 2 & 4 stroke but my experience with outboards is very limited.

Any help would be appreciated.

Thanks
Steve"
 
Just read another post about a

Just read another post about an Evinrude 89' 25hp carb linkage/timing issue. We did mess with a stopper/stud that was on the starter bracket and screwed it all the way in. Is that part of the timing system. If so I did mess with the timing.....

Thanks
Steve
 
Would this cause the backfire?

Would this cause the backfire??? If so how do you set that timing stop?

Any help appreciated.

Thanks
Steve
 
if you have got the synchroniz

if you have got the synchronization off it will sneeze and backfire-------thats the lil cam thing that moves at the same time as the timer base....it opens the carb.
it should not be touching the lil plastic roller at idle.

i gave you a method for setting the timing on your other post..........but if you really want it ot be correct you will have to do it on the water at wide open throttle.

you can get partial repair manuals on googlebooks.com ...........if you are going to work on it at home you really need a book of your own
 
by the way--- NEVER use starti

by the way--- NEVER use starting fluid on a 2-stroke..........if you need to prime it maually use pre-mix in a spray bottle.

the oil in the fuel is the only lubrication you have....and starting fluid has no oil.
 
Did you remove the coils or sp

Did you remove the coils or spark plug wires?

Even if the synch is out by a country mile the motor will still start and run however bad.

Set the low speed mixture screw at 1&3/4 turns out and once running and warm adjust...wind in untill best running is achieved and then turn the screw out about a 1/8 of a turn and it should be ok.

These engines are easy to synch staticaly and the max timing never changes with wear or age.
 
"The main jet in the bottom of

"The main jet in the bottom of the float bowl is plugged, the idle draws here also, backfiring is from being lean.

Dan"
 
David.....I will follow that p

David.....I will follow that procedure and quit using starting fluid.

Jamie...We did not mess with the plug wires.

Dan....There is a main tube that goes to the bottom of the bowl and inside is a smaller tube. Should that smaller tube be hollow. if so it is really clogged.

Thanks guys if you think of anything else I am all ears.
 
"Stephen the carby is still bl

"Stephen the carby is still blocked you are going to have to give it a good clean, once you have it cleaned i use a spray can of carby cleaner with a nozzel to spray through the idle, intermediat and high speed circuits to ensure there are no blockages"
 
"here is a carb cleaning link.

"here is a carb cleaning link....it walks you through the process

http://forums.iboats.com/showthread.php?t=244013

you will need some wire, carb cleaner, and preferably compressed air........carb kits would be great also, but if you are careful and your gaskets and needle are in good shape you may be able to scrape by for a while.....if your needle has a little ring around the top you can gently twist it back and forth on some fine sand paper to remove the groove..or emery cloth"
 
"NEVER use starting fluid on a

"NEVER use starting fluid on an outboard.
As David says, there will be a no oil condition when it fires up on the ether.

Also, and this is verified...ether starting fluid on the plastic venturis of plastic carbs will wrinkle and bubble the plastic surface of the venturi bore. This disrupts the air flow ever so slightly, causing turbulence in the venturi. This turbulence changes the air pressure difference between front and back of venturi, and then it does not draw enough gas up from the high speed jet and fuel bowl. What is the result? Lean running at high speed, and a burned piston. Guaranteed! I'll show you one!!!"
 
"Stephen, the main jet that is

"Stephen, the main jet that is plugged is not visable, it's in the passage in the bottom of the float bowl where those brass tubes fit into.

Dan"
 
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