Won't Rev.

[whisper]

Won\'t Rev.

Friend has a 70 hp Evinrude 4 stroke(nee Suzuki).
Ran like clockwork for 2-3yrs but had a service, which may or may not be significant, about 18 months ago. Since then when he goes out to sea he'll open it up and as soon as he gets to around 3000rpm it cuts out, misfires and often stops.
Dealer has looked at it on a number of occasions and thought it was a fuel feed problem from the main tank - since disproved.
I know that the cooling water tell-tale used to be a steady flow at tick over and a positive torrent at higher revs - now there is no flow at all at tick over and a weak stream at higher revs.
Any suggestions please.

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[nordic_ranger]

Re: Won\'t Rev.

It might be worthwhile posting your friends problem here. http://www.outboardrepairs.com/evinrude/
It is a huge site full of helpful advice.

Jim.

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[Dave_Snelson]

Re: Won\'t Rev.

Quite possibly overheating. Suzuli protect their engines in a variety of ways, one of which is overheat shut down. A sensor on the block triggers the management unit to shut the engine down to a low rev range once it detects an overheat situation. It also does this with an oil flow or level situation.

A weak tell-tale is indicative and significant here. First poke a small wire up the tell-tale and make sure it isn't blocked (doubt it) and then seriously consider (and by that I mean you should do it this weekend!) stripping the lower leg and replacing the water pump impellor kit. They only have a service life of 3 years anyway.

<hr width=100% size=1>Madoc Yacht Club
<A target="_blank" HREF=http://www.madocyachtclub.co.uk>http://www.madocyachtclub.co.uk</A>

 

[Fingers]

Re: Won\'t Rev.

I had an old Mercury Blue Band 50Hp a few years ago with the same symptoms. It would tick over and pootle about ok, but when you opened it up it would die.
I found the fault was with the electrics. There was a round black connector that fitted into the engine, connecting back to the throttle control. This had become coroded inside and would heat up and cut out at higher revs.

<hr width=100% size=1>Nil Illegitimi Carborundum!