Yamaha 9.9 "deaths"

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Yamaha 9.9 "deaths"

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Yamaha 9.9 "deaths"

Posted by Grog (Morning Song) on June 11, 2002 at 07:24:00:

The Newsletter reports "that there were a few outboard engines that died in the
Bahamas this year". We have the same engine identification. Any information
would be appreciated

We are currently trying to solve a problem of an engine which will run at full
power for about five minutes before it starts to fade and then resume full
power. It fades for about one to two seconds before resuming power. At times it
surges and fades repeatedly - cycling every few seconds. We have used a separate
fuel tank and cleaned the carburettor etc., The local dealer has had the engine
off the boat four times so far with no success. Our current guess is the oil
pressure switch which is being replaced today

- Grog

Follow Ups:

Re: Yamaha 9.9 "deaths" Dan Hofmann 04:17:43 07/05/02 (0)
Re: Yamaha 9.9 "deaths" Captain Hank Walden 13:31:55 06/13/02 (0)
Re: Yamaha 9.9 "deaths" Marc Gershel 07:33:35 06/11/02 (4)
Re: Yamaha 9.9 "deaths" Grog (Morning Song) 11:05:50 06/11/02 (3)
Re: Yamaha 9.9 "deaths" Roger Pollard 21:56:11 06/12/02 (0)
Re: Yamaha 9.9 "deaths" Roger Ford 12:16:25 06/12/02 (0)
Re: Yamaha 9.9 "deaths" Colin Swithenbank 17:05:59 06/11/02 (2)

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Re: Yamaha 9.9 "deaths"

Posted by Dan Hofmann on July 05, 2002 at 04:17:00:
In Reply to: Yamaha 9.9 "deaths" posted by Grog (Morning Song) on June 11, 2002
at 07:24:00:


Have you checked the wires that run across the top of the engine to the oil
sending unit to make sure that it is not worn through? You could probably
disconect that wire, ground it and see if the problems goes away. That way you
could prove to yourself that the sending unit is functioning or not

I am still chasing a problem in my spare engine that looses power and then dies
out completly. I hope to borrow a stator and stick it on there to see if it is
that

Good luck. Keep us posted

Follow Ups:

Re: Yamaha 9.9 "deaths"

Posted by Captain Hank Walden on June 13, 2002 at 13:31:00:
In Reply to: Yamaha 9.9 "deaths" posted by Grog (Morning Song) on June 11, 2002
at 07:24:00:


One of my Yamaha engines would die at idle or slow revs. I traced the problem to
an old water separater that allowed too much air into the system. The problem
was resolved with a new water seperator.

Follow Ups:

Re: Yamaha 9.9 "deaths"

Posted by Marc Gershel on June 11, 2002 at 07:33:00:
In Reply to: Yamaha 9.9 "deaths" posted by Grog (Morning Song) on June 11, 2002
at 07:24:00:


Hi, I had a similar problem. It turned out to be a dirty oil filter. I would
clean the filters between oil changes with carb. cleaner to extend thier life

May be good for one cleaning,but that's it. A new filter solved the problem

Marc

Follow Ups:

Re: Yamaha 9.9 "deaths" Grog (Morning Song) 11:05:50 06/11/02 (3)
Re: Yamaha 9.9 "deaths" Roger Pollard 21:56:11 06/12/02 (0)
Re: Yamaha 9.9 "deaths" Roger Ford 12:16:25 06/12/02 (0)
Re: Yamaha 9.9 "deaths" Colin Swithenbank 17:05:59 06/11/02 (2)

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Re: Yamaha 9.9 "deaths"

Posted by Grog (Morning Song) on June 11, 2002 at 11:05:00:
In Reply to: Re: Yamaha 9.9 "deaths" posted by Marc Gershel on June 11, 2002 at
07:33:00:


Thanks for prompt reply. No! Not the oil filter - we changed that

- grog

Follow Ups:

Re: Yamaha 9.9 "deaths" Roger Pollard 21:56:11 06/12/02 (0)
Re: Yamaha 9.9 "deaths" Roger Ford 12:16:25 06/12/02 (0)
Re: Yamaha 9.9 "deaths" Colin Swithenbank 17:05:59 06/11/02 (2)

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Re: Yamaha 9.9 "deaths"

Posted by Roger Pollard on June 12, 2002 at 21:56:00:
In Reply to: Re: Yamaha 9.9 "deaths" posted by Colin Swithenbank on June 11,
2002 at 17:05:00:


I had the same problem with the port engine in 1998. I tried everything but
nothing helped. I finally swapped the port engine with the starboard engine and
haven't had the problem since. I do not know why, but the engine no longer
stalls.

Follow Ups:

Re: Yamaha 9.9 "deaths"

Posted by Roger Ford on June 12, 2002 at 12:16:00:
In Reply to: Re: Yamaha 9.9 "deaths" posted by Colin Swithenbank on June 11,
2002 at 17:05:00:


Colin - did you see any trend to the temperature readings? Were they generally
consistent or relative to the sea temp? Were you taking readings of the water
coming from the little stream?

Follow Ups:

Re: Yamaha 9.9 "deaths"

Posted by Colin Swithenbank on June 11, 2002 at 17:05:00:
In Reply to: Re: Yamaha 9.9 "deaths" posted by Grog (Morning Song) on June 11,
2002 at 11:05:00:


Grog (??):[/i]

Hi! These Yamaha engines are fitted with oil pressure sensors which reduce rpm
if the oil pressure drops below the set level. Low oil pressure can be caused by
old oil or even by high oil temperature. Try replacing the oil and if this
dosn't work, replace the thermostat. I carry an infrared thermometer which
indicates coolant temperature after having had a few thermostat failures

Colin
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