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Random Quote: A smooth sea never made for a skillfull sailor...lannyard
Bluefin, I have never seen a Yamaha burn 100 to 1 on oil. There might be one ,every so small, rpm range that it does but every Yamaha I have ever operated burns around 50 - 1 to 60 - 1 at best. That real world data not something printed in a add. My last Yamaha breakin said to premix at 50:1. Yamaha's have never been oil misers.
There is only so much I can try and do from a laptop...on a rainy Saturday...in Burlington, VT.
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Everything BD has said is right on, and I have zero doubts concerning the problems he's having.
Like I said, there's not too much I can see right now, but a few things jumped out at me.
One, I've never heard of this dealer in Baltimore. It appears he's been a Yamaha packaging dealer for less than a year. Perhaps they've not had sufficient time/resources to get some guys down to Georgia for Service School. ??
Also, the system currently shows zero warranty claims in for this motor. None submitted, none in proces, none refused...nada.
That by no means invalidates the story, but it does make me wonder where these guys got a powerhead, or if our RTAs simply didn't get it in. ???
Anyway, it sounds like things are progressing properly and a Yamaha RSR will be coming in to take a peek. Believe me, NOBODY hates blown powerheads more than we do. Esp. repeats. It's simply wasted time/money because someone decided to be a parts-changer instead of properly diagnosing the root problem first.
In the times I have seen similar failures to this, it's almost always been a fuel-system vacuum issue on the boat. Many times it's somethign as simple as a tie-wrap on the rigging hoses being too tight. Sometimes the boatbuilders use fuel hoses too small. Sometimes there is a crimp in the line somewhere.
Unfortunately, checking the vacuum rarely is done.
I'd like to hear what it's pulling when you get it checked.
Anyway, I hope this gets resolved ASAP. I'm sorry you've had to be without a boat this long.
I agree with the air scenerio if you are pumping directly to carbs via a mechanical pump. Not EFI, especially since the electric fuel pump on the out side of the mechanical fuel pump is emersed in a vapor canister. The canister fills up with fule much in the same manor as a carb bowl. But there is one catch, the electric fuel pump pickup is at the bottom of the canister. Gas does not foam to the extent to have the entire vapor canister become a beer keg. Also if the fuel pump was not delivering fuel it would effect all injectors and all cylinders. The required pressure would drop, and you would have performance issues. As Dixon has stated the vacuum test is for fuel pull, making sure there is no leaning
Hawkeye, I went back to double check my maintenence books. We're both partially right. [img]/infopop/emoticons/icon_wink.gif[/img] From what I could find, there there is a difference in oil ratios among Yammies.
- Up to about 60hp, they normally run on 100:1 oil ratio. They use 25:1 ratio for breaking in.
- 70hp and above, they seem to run on 50:1 oil ratio.
- For fuel injection models, the normal ratio varies from 200:1 to 50:1. You use 50:1 oil pre-mixed in the gas tank for breaking in.
So Browndog has used the correct recommended oil ratio. It goes to show you that it is important to check the spec for the particular model.
Quetion,
I just bought 12 (Yes, one dozen) Merc Optimax 200 HP motors for my fleet. As I opened up the boxes right from the factory, 11 of them would not start. Finally, with a Merc mechanic's help, I was able to get 2 of the 11 started. BUT, both of the two blew the power heads just idling for 5 minutes right out of the box. The 12th motor, started right up, but it runs weird and has blown two lower units in about 8 hours.
