Outboard Size on Easy 37

Outboards or inboards, electric, fuel or diesel, cavitaion and torque talk
Bligh
Posts: 13
Joined: Thu Apr 23, 2009 9:43 pm
Location: Mandurah, WA

Outboard Size on Easy 37

Post by Bligh » Wed Dec 16, 2009 12:22 am

Thanks for all the advice.



Maybe I'm missing something here - I can typically only get 4 knots at 3000 rpm with my 9.9's. (An experienced outboarder suggested I don't go above this). If I could get 6 or 7 knots that would be great.



On using the tides, good point, but I guess the NW of Australia is remote and with potentially big distances between anchorages, so for safety's sake I would like to know that I've got the grunt to get out of trouble if I mis-judge.

44c
Posts: 1148
Joined: Tue Aug 08, 2006 5:08 am
Location: Hervey Bay, Qld

Outboard Size on Easy 37

Post by 44c » Wed Dec 16, 2009 1:18 am

Don't go above 3000 RPM???? Does he think you have diesel outboards?

Bligh
Posts: 13
Joined: Thu Apr 23, 2009 9:43 pm
Location: Mandurah, WA

Outboard Size on Easy 37

Post by Bligh » Wed Dec 16, 2009 6:56 am

Hmm... might be onto something here. I'll give it 5000 to 6000 rpm and see how we go.



Thanks CoS

puremajek
Posts: 753
Joined: Thu May 04, 2006 7:36 pm
Location: Brisbane Australia
Contact:

Outboard Size on Easy 37

Post by puremajek » Wed Dec 16, 2009 8:11 am

Bligh



We get 5200 rpm at max and normally cruise 4200 - 4600.



If you find you can't get anymore than 3000rpm (or thereabouts), its normally an rpm gauge issue. In your case though it does not sound like a gauge issue given the speed you are getting.



Wind them up I say.
James
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Smooth Cruiser
Posts: 583
Joined: Thu May 11, 2006 1:51 am
Location: Brisbane

Outboard Size on Easy 37

Post by Smooth Cruiser » Thu Dec 17, 2009 6:14 am

These size outboards are quite happy to run at wide open throttle for periods. Of course they will use more fuel (increasing exponentialy with revs!) but if you need them they can rev right out.



Not sure if you mean you physically can't make them go above 3,000rev or you haven't tried on advice to restrict revs. If you can't get them to rev harder and you have cables to remote controllers, then try pulling the cowl off and opening the throttle fully by hand (turning the cam that the cable attaches to). I fthat gets more revs then your cables are set up wrongly or have a restriction.



If it's advice - it may be in order to limit cavitation. Certainly you will find in rough water you can't hold the outboards higher than about 2/3 WOT without the props starting to cavitate - however I find even when I back off until cavitation is reduced then I am still getting around 5-5.5 knots with both engines.



Let us know how you get on. Happy to answer any specific queries via PM or here, as it would seem we have the same engines on the same boat.

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