I fished two tournaments last weekend the temp was upper 90's and humid. On Sat. was going to run to another spot and had to pump the ball up to get it to start. Day two had to pump the ball up 3-4 times and the motor died running in to weigh in.
Is this normal for Yamaha's? This is the first one I have owned any ideas?
Thanks
For all brands. Vapor locking (vaporization-boiling off ) of fuel system is a major problem on the draw, suction, side of your fuel system more so in hotter climates. Therefore i recommend as the other moderators have, to temp bypass your boat fuel system with a known good portable tank, ( 5/16 minimum line and fittings and vent open) and see if your boat corrects the running issue yiou have. next test is a fuel pressure gauge at the VST schrader fitting. Thanks, David.
<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by flippin101 »</td></tr><tr><td class="quote">I fished two tournaments last weekend the temp was upper 90's and humid. On Sat. was going to run to another spot and had to pump the ball up to get it to start. Day two had to pump the ball up 3-4 times and the motor died running in to weigh in.
Is this normal for Yamaha's? This is the first one I have owned any ideas?
Thanks</td></tr></table>
No, it's not normal. I don't think I have had to pump my bulb since I did my last filter change last year. Normally my HPDI fires right up without touching it.
What engine (year/model/hp)?
In addition to the good advise David gave, just remember once you pump up the bulb and start the motor, the motor is now sucking a vacuum against the bulb. This is what continues to draw fuel to the motor. So, it's normal for the bulb to no longer be hard after you run the motor.
Now having to reprime the fuel system to get it to start shortly after stopping is another story. That would be a good sign of a vaccum leak on the engine side of the bulb. It sounds like it may be a small one as the motor is still running once primed, so it may be hard to spot.
The easiest ways I know of to see if there is any fuel leaks in the fuel system between the primer bulb and the engine, is to shut the engine off and pump the primer bulb as hard as you can. Then start looking for leaking fuel . The fuel system is under pressure with that bulb pumping, and anywhere fuel is leaking is a place air can be sucked in when the engine is running since those areas are now under vacuum. Prime place to start would be around the on engine fuel filter and the low pressure fuel pump block bases.
Or, the low pressure fuel pump(s) may be starting to go also. Info on the motor type/year/hp will help give an idea of what your pressures should be and where to measure them.
Or, the VST or medium pressure filters may be clogged (or on the verge of clogging). Pumping the bulb makes you a "supplemental fuel pump" and puts additional pressure on the system. May be just enough to flow additional fuel across the filters to get it started, but while running it starts to starve for fuel and dies. Loss of RPM and stalling are signs of filter issues most of the times in a Yamaha.
Just a few thoughts.... Start with the easy stuff and work your way down from there.
My V-Max 150 is doing the same thing. Had trouble loading it on the trailer. 2 Evinrudes also did it at the ramp.
<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by Skeeter ZX-190 »</td></tr><tr><td class="quote">My V-Max 150 is doing the same thing. Had trouble loading it on the trailer. 2 Evinrudes also did it at the ramp. </td></tr></table>
That sounds like a weather induced issue to affect motor from different makers in the same way (or fuel from the same source?).
I know hot, wet air does not produce as much horsepower in any normally aspirated engine as cold dry air which is more dense. That's a fact of physics of the way an internal combustion engine works.
At work the guys who pilot the 3 helicopters are much more concerned with weight load in the Georgia July heat for the same reason. In January they don't bother to calculate it, but in July it matters (and I've flown with them in both hot and cold and even my untrained butt can tell a difference in the response). So if it effects jet turbines which use compressed air you know it has an effect on a outboard.
I pumped the ball up and did not feel it bleed off, checked the vent in the fuel cap andI did not find any obstructions.
The boat is a 2003 196 Champion with 200hp Yamaha hopefully it was just the hot humid weather. I had a Yamaha dealer do the spring check up which included changing the fuel filter.
I have another tournament in two weeks so I guess I will see what happens.
Thanks for all the good info.....
Here I go again on the ethanol thing. But if it is really vapor locking ethanol will make it worse due to its lower vapor pressure. Larger fuel lines and fittings will help this. Premium fuel will also help this most premium fuel has a higher vapor pressure. A low pressure electric fuel pump in the boat is another fix for vapor locking.
who did you send im to
So what was the fix for this problem??
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