fuel system problems
Submitted by Rig on Thu, 2010-01-21 16:52
Hi all
I have a 97 johnson 40hp. when i am running the motor under 2000rpm it starts to cough and conks out. when cruising at higher revs no problem or if i keep the revs up in neutral. after speaking to my boat mechanic he said it is either the fuel line kink or leak or the fuel pump needs replacing which is about $600 plus labour. I have replaced the entire fuel line to no avail. i was thinking it could be sediment etc blocking the carby or something. does anyone have any other ideas solutions
cheers
rig
nackers
Posts: 341
Date Joined: 23/10/09
sell it
and buy a yammie %)
Paul G
Posts: 5215
Date Joined: 12/12/07
Have you changed the filter
Have you changed the filter if you have one.
Active Gyp-Rok solutions ,Residential and commercial ceilings and walls
just dhu it
Posts: 1081
Date Joined: 14/05/09
fuel pumps
you may have to go to an service agent , some of the motors run two fuel pumps one for a certain lower rev range and then another when running at higher revs.
PJAY
Posts: 1005
Date Joined: 12/05/09
have a look at the o rings
have a look at the o rings on your motor and fuel ine connection. Had a similar prob with a 30hp yammie it was sucking air. replaced the fuel line and motor o rings and it was fine after that...
The Kimberley....perfect one day and more perfect the next!!!
Rig
Posts: 2925
Date Joined: 27/12/06
has new filter hey pjay
has new filter
hey pjay are these o rings actually in the power head.
i noticed tonight when inspecting it that the fuel hand pump was leaking again. i got a new kit to replace the old one. when i squeeze the bulb a little bit of fuel leaks. maybe i have had 2 dud ones in a row or is this common/ meant to happen.
dont worry nackers i would rather have a yami
PJAY
Posts: 1005
Date Joined: 12/05/09
nah rig the o rings are on
nah rig the o rings are on the end of the clip on fuel line or where the fuel line attaches to the motor
The Kimberley....perfect one day and more perfect the next!!!
wide open
Posts: 444
Date Joined: 24/12/09
ok its a 2 stroke and fairly old
so i think that you should definetely have carburettor cleaned.
do you run off the fuel when you flush it so oil does not gum up in the carby
when the problem started on the first drive was the motor left not started for a long time.
and having a air leak on 2 stroke dirt bikes usaauly causes a exceccevly high idle
but on our boat the fuel bulb does not leak at all so i would definetly fix that up.
how often do you use the boat
Rig
Posts: 2925
Date Joined: 27/12/06
i use it a fair bit minimum
i use it a fair bit minimum once a fortnight usually more. but i bought it about 3 months ago so before that it probably wasnt used much. the idle doesnt speed up like a dirt bike. i run it dry but cant speak for previous owners
wide open
Posts: 444
Date Joined: 24/12/09
is the fuel leaking out
were the hose meets the fuel bulb that you squeeze to prime it?
i dont know why that would be leaking if you changed it, our motors does not leak at all
maybe the carb nees cleaning maybe the jets are partly blocked.
i would try do the cheap fixes before throwing $600 at it
take the leaking bulb back to the shop
greasemonkey
Posts: 112
Date Joined: 08/05/09
Carby
I had a very similar issue with one of my old motors . It turned out to be crap in one of the carbys . It only takes a small amount of crap to cause a big problem .
Rig
Posts: 2925
Date Joined: 27/12/06
yeah i got a new bulb today
yeah i got a new bulb today and i am also replacing the plug on the end of the lead that goes into the motor. i need to get my hands on a service manual
wide open
Posts: 444
Date Joined: 24/12/09
if that doesnt
fix it i say its the carb its party blocked
kane
Posts: 1752
Date Joined: 07/12/08
if it coughs and splutters under 2000 rpm ...
but runs ok at higher rpm its probably not a fuel problem, obviously the more rpm the more fuel your sucking so if it runs ok at high rpm its getting enough fuel.
at low rpm id be more inclined to check your spark plugs and leads
Gooooone Fishin!
Rig
Posts: 2925
Date Joined: 27/12/06
yeah new plugs, it was tough
yeah new plugs, it was tough at times to get it to full throttle, i am gonna take it to boat city next week maybe they are a johnson dealer
PJAY
Posts: 1005
Date Joined: 12/05/09
rigg it could be worse
rigg it could be worse mate.........you could have a westbend or chrysler motor. Then the problem is easy identified.............they are both boat anchors! lol
good luck getting it sorted.......let us all know the outcome...
The Kimberley....perfect one day and more perfect the next!!!
wide open
Posts: 444
Date Joined: 24/12/09
maybe
you sya if it was tough to get to full throttle maybe its not getting enough fuel