Yamaha 1999 150 outboard

kitty kat

Cadet
Joined
Jul 6, 2015
Messages
11
change my lower unit fuel pump now when I get the motor up I could see gas coming out the back of the motor can you explain to me why
 

kitty kat

Cadet
Joined
Jul 6, 2015
Messages
11
my lower pressure fuel pump went switched it out now when I lift up the outboard motor I could see gas coming out the prop or underneath the boat could it be that I didn't steal the gas here on correctly on top of the fuel pump housing
 

kitty kat

Cadet
Joined
Jul 6, 2015
Messages
11
change my lower unit fuel pump bolt was running good today I come in I left the motor of I can see gas coming out the back of the engine motor
 

kitty kat

Cadet
Joined
Jul 6, 2015
Messages
11
change my lower unit fuel pump motor was riding good came in with my motor up and I could see gas coming from behind the Motor did I miss something or somebody help me
 

99yam40

Fleet Admiral
Joined
Sep 7, 2008
Messages
8,851
Might want to pay attention to what you are writing.
There is no lower unit fuel pump that I know of
 

99yam40

Fleet Admiral
Joined
Sep 7, 2008
Messages
8,851
maybe a lift pump you are speaking about?


Fuel injected or carbed motor?
Complete model # would help all try to figure out what motor you have
 

kitty kat

Cadet
Joined
Jul 6, 2015
Messages
11
feel like the engine is still starving for gas where should i look at it ,out today in you can feel the surge and rpms surge under load coming back in at 4 miles per hour the boat just want to shut down
 

kitty kat

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Joined
Jul 6, 2015
Messages
11
I have a 1999 150 Yamaha 2 stroke ox 66 out borad change the high pressure pump two fuel pumps and the Boat is still starvingfor gas can anybody out there give me a idea where to look at check the fuel pump pressure pressure is coming out good but the engine still missing when I go to start it starts up 20 seconds then shuts down sometime when I started up and stays running but the RPM surges up and down at the dock when I left the lever up in neutral and goes from 20 rpm to 26 rpmthen when I back it down it will stay idle perfect but sometime when I started doesnt start up and run for 20 seconds and stop missing again
 
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kitty kat

Cadet
Joined
Jul 6, 2015
Messages
11
how you doing I have a 1999 150 outboard Yamaha SxtLrX ox66 fuel injection I change high pressure both fuel pumps theboat still want to stall out 600 RP M's anything over 600 rpm the boat is Running fine while driving the Boat I can feel the RPM's go up but do still have a little slurred in it as I Drive the boat can anybody tell me why the boat is stalling out under 600 rpm
 

Propwash79

Cadet
Joined
Jul 12, 2015
Messages
26
Sorry but sounds like your all over the place. I t sounds like a fuel pump issue sucking air and that's why it surges. How does it idle and does it shut down? You said that is leaking fuel and that should be very obvious that something isn't put back correctly and posses a fire hazard and worse an environment hazard and you don't want the local law or coast guard seeing that.
 
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