Motor dies after planing out

[mcgreavster]

88' XP 150 will idle perfect all day long, I'll go to throttle down and it gets up on plane really quick with lots of power and everything seems great until about 15-20 seconds later when the motor just dies. It doesn't seem to sputter or matter if I back off the throttle, it seems to just be instantaneous so I'm thinking an electrical issue? It'll start right back up after and it'll be the same as before.

My tach hasn't really worked since I bought the boat late last year (kicks on for a minute or two here and there). So today I moved my gray tach wire from the rectifier to the yellow/gray stator wire and the rpm tach started working again. Also I checked the volts on my battery before running it (12.7V), during running (12.56V), and then again after I shut motor(12.67V).

So I for sure have a bad rectifier but I don't know if that would cause my motor to die after full throttle? I've read it might be more of a Stator or Powerpack problem? By the sounds of it running with a bad rectifier can eventually cause your stator to overheat, and after inspecting my stator from under the flywheel it does appear to have some black possibly melted material on it.

Does anyone have any ideas what my problem might be?

 

[boobie]

Have you tried pumping the primer bulb when this happens ??

 

[mcgreavster]

Have you tried pumping the primer bulb when this happens ??

I haven't got to mess with it much because it didn't start happening until the end of last season and I Iive up north so no open water till April. But it only happens at WOT so I can't really test it out of the water and can't prime the bulb when I'm driving the boat. Also not sure if I have anyone who wants to sit on the back of my bass boat when the motor dies at 50+ mph(the only time it dies)

 

[jimmbo]

How did it run at high speeds that were lower than full throttle? The last 1500 rpms really make the motor thirsty. If it runs ok there, could be air leaking into the fuel line, could be restricted fuel line/filter. Primer bulb will be flattened if there is a restriction prior to it.

 

[boobie]

Where's up north ??

 

[mcgreavster]

How did it run at high speeds that were lower than full throttle? The last 1500 rpms really make the motor thirsty. If it runs ok there, could be air leaking into the fuel line, could be restricted fuel line/filter. Primer bulb will be flattened if there is a restriction prior to it.

Seems like I could run at 75%~ throttle and be fine. I just replaced the primer bulb and fuel filter today. Unfortunately can't test it on the water till next month.

 

[jimmbo]

You can check things like the fuel pickup for dirt or jelly. With time fuel lines can deteriorate internally. Fittings and hoses checked for leaks. The Primer Bulb fittings are notorious for leaking air in.

 

[mcgreavster]

You can check things like the fuel pickup for dirt or jelly. With time fuel lines can deteriorate internally. Fittings and hoses checked for leaks. The Primer Bulb fittings are notorious for leaking air in.[/QUOTE

By fuel pickup do you mean at the tank? I've got 2 tanks and I have the same problem regardless of the tank I'm using. The primer bulb I replaced didn't have a clamp on the outgoing end so Hopefully it's just something simple like that. Once I found out my rectifier was bad I thought I might have electrical issues.

 

[mcgreavster]

Where's up north ??

Michigan

 

[bob johnson]

I cant imagine a fuel issue...as the motor just dies.... any fuel issue at WOT would show itself at ALMOST wide open throttle... I am wondering if you have a short from the extra vibrations at WOT....just a guess.... I would think a fuel issue would make it sputter.....and slow down fast...NOT kill the motor. good luck

bob