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2003 175 johnson

bjustice

New member
i have a 2003 175 johnson , i have to choke it most of the time to keep the motor running until i get to full throtle , when i stop for awhile the fuel bulb loses prime , i have to reprime it and still have to choke it , local mech said it was fuel pump problem , any suggestions
 
choking a motor to make it not stall..usually means it is not getting enough gas..... so a fuel pump is a possibility.....or a dirty carb.... a primer bulb that goes very soft, usually means an air leak.....if there are no leaks the column of gas in the line all the way to the fuel pump.....has no where to go...so it is sitting there for the next time you want to start the motor!!, which means maybe the bulb squeezes slightly....and then stays firm...


if yours does not do this....it means you have an air leak some were

good luck

bob
 
Thanks, already had the carbs cleaned and it still does it , replaced primer bulb also , i can pump the primer bulb and it gets firm and stays that way until i run the boat for awhile then after fishing a few min that is when it does it , could there be a prob with the fuel tank or do you think it would be in fuel lines causing a leak
 
So your saying it runs fine wide open? If that is the case it would not be a fuel pump, right? Maybe mixture screws are not set right.
 
well the back fire might be a clue... i wonder if you are running on all cylinders...and might be dumping raw gas that isnt getting fired out the exhaust and it ignites there....

you have 6 cylinders...it is possible 5 are carrying the load...especially if you have a LEAN condition....leaning a motor out gives it a little more power and rpms...

I still think since you lose the prime, you have an airleak....but that shouldnt be the reason you have to choke the motor to start it... do you Prime the motor with the key push??

that is HUGE...i am having an issue with with my electric primer solenoid.. and found the motor was very hard to start... the key push was doing nothing!! i threw the red lever down and squeezed the gas line bulb, and wham.. the motor fired over..... the hard start was because it wasnt getting gas!!......your motor probably has the primer solenoid... pull a hose off the manifold and have someone push the key in to activate the primer....see if it squirts gas.


other than that you really should start are ground zero.....

make sure the motor have a LINK and SYNK done... check to make sure you have strong spark in all cylinders...check to ake sure you have equal compression in all cylinders...

if you have good spark....and your timing is set right...you concentrate on the fuel mixture......people rebuild carbs all the time and they miss something..

you realize in regaurds to the gas bulb losing prime, that there are a ton of gas line connections on that motor where air could get in!! TON!

viejito
 
thanks viejito, the motor will start without choking , but when i go to give it fuel that is when it dies but if i choke and give fuel at the same time it will run
once i get going it does not need to be choked anymore seems like it is mainly on the takeoff, as far as the gas lines go is there a way to check them all or would it be good idea to replace them
 
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Pull the pulse limiter line off on the vro pump and make sure there is no fuel present.

whats that a sign off...a torn diaphram in the fuel pump???

try this: turn all the idle mixture screws in till they seat and then turn them out 6 full turns( my 1997 manual says 5 turns...but we want to make sure you get enough fuel)( also if you have a 2003 manual and it says a different # of turns..then do that)....outside of that, id look at dissasembling the carbs again an dmaking sure everything is spotless and you run a wire through all the passages...and you make sure you have a good seal on all your gaskets.....( an air leak will lean out your mixture...which is your issue...not enough gas)

beyond that.. you may need to visit a linkage-timing-syncronization proceedure.....which i have never done up to this point..


(PS): your year motor MIGHT have a special idle needle head, that could require a special tamper proof torx style screw driver to turn!!!....I hope not....sometimes you can drill a hole in the middle of a regular torx head tip and it will work

bob
 
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