2005 Yamaha 150 - 4 stroke NEEDDS Help!!!

[mak9504]

Does anyone have any ideas to help me. Engine ran great till we went to a restaurnant on the lake. After dining, it wouldn't start. The motor turned over, but wouldn't start. I have been using non-ethonal gas. I checked the fuses. I checked the fuel filter. Had it towed to the mechanic. They couldn't find anything wrong and it started every time. I picked it up two days ago, and it started fine and ran perfect. Started it a few times that day and it started up each time. I tried to start it today and again, it won't start. Any ideas would be appreciated. Thanks, Al.

 

[divinginn]

Re: 2005 Yamaha 150 - 4 stroke NEEDDS Help!!!

I had a friend that had a problem with the kill switch doing the same thing.

 

[mak9504]

Re: 2005 Yamaha 150 - 4 stroke NEEDDS Help!!!

do you mean that his kill switch was faulty. What did he do. Thanks, al.

 

[rodbolt]

Re: 2005 Yamaha 150 - 4 stroke NEEDDS Help!!!

if the kill switch is faulty you will get an alarm while cranking.
can you hear the fuel pump whine for about 5 seconds at key on power?

 

[mak9504]

Re: 2005 Yamaha 150 - 4 stroke NEEDDS Help!!!

Thanks for your reply. The alarm does not sound while cranking, so that is eliminated. While power is in the ON position, I sometimes hear the whine from fuel pump but not all the time. I also hear clicking in the fuel rack, but also sporadically. I am getting a spark on all 4 cylinders, but the spark plug is dry. Any other ideas. Thanks again for a reponse. Al.

 

[rodbolt]

Re: 2005 Yamaha 150 - 4 stroke NEEDDS Help!!!

check fuel rail pressure and test fuel pump voltage.
the yellow red wire has 12V positive anytime the key is on.
pump ground path is the blue wire through the ECU.
blue wire will be grounded for about 5 seconds at key on power.
the chatter you hear at key off is the ISC valve resetting for the next start cycle.

 

[mak9504]

Re: 2005 Yamaha 150 - 4 stroke NEEDDS Help!!!

Rodbolt - You're the best. I'm going to try your ideas now. or do I need to have a fuel injection pressure tester. Can I use anything else. Could it be a sensor holding it from starting??? I'll let you know how I make out with the pressure. Thanks again, Al.

 

[mak9504]

Re: 2005 Yamaha 150 - 4 stroke NEEDDS Help!!!

Hi, again. I checked the voltage on the yellow red and the blue and both worked out okay. I checked the fuel pressure on the fuel rack and there is NO pressure. Do you know where I can go from here. You've been a big help, since I was now able to eliminate a few things. I appreciate it. Al.

 

[rodbolt]

Re: 2005 Yamaha 150 - 4 stroke NEEDDS Help!!!

if your pump volyages are correct and you have no rail pressure then test the pressure regulator and the pump.
pull the VST and inspect the filters.
there is one just above the VST and one in the VST.
if the voltage is correct and the pump doesnt run its sad news.
use some paper clips to back probe the VST pump connector at the fuel rail connector. key on you should read 12V for 3 to 5 seconds then nothing.
while the 12v is there you should hear the pump whine.
no whine at 10.5 to 12V means a pump issue.
what part of the thicket lump state do ya be in?

 

[mak9504]

Re: 2005 Yamaha 150 - 4 stroke NEEDDS Help!!!

Thanks for all your help. I have tried all those things and yes, it's sad news. It's sure looks like it's the pump. We're on Lake Murray in S.C. and I hate to call the local marina, but this job looks a little too big for me to do in the water. You were great, though, with your ideas and I appreciate it. At least it might have narrowed down the problem. Thank you, thank you, thank you. Al on Lake Murray.