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Hello All,

We enjoyed a successful first outing on the weekend with our 18. We did about 125 miles in and around the many inlets and channels surrounding Nootka Island on a Salmon Fishing trip.

Now that the boat is up and running, I want to fine tune the setup of the engine, as it is currently mounted in the lowest position, which after much reading, I realize is not optimum.

We have an OMC SST 14.5 x 19" prop, part number 389924. The boat has never had bottom paint.
I understand our target rpm range for this engine is 4500-5500 but I'm not positive of this?

First WOT test, loaded with about 800 pounds of people and gear, 3/4 full of fuel, plus a 100lb kicker engine, full throttle showed about 4600 rpm and 36 mph by GPS, on calm water, somewhat trimmed out. On another test, without the kicker and loaded with maybe 400 lbs, I saw 4800 rpm and 37mph.

I've seen comments of moving the engine to 2 holes up, and a 10 year old remark that Whaler recommended 1 hole up.

The boat will see all around use, from towing kids on tubes in the lake to the odd offshore salmon fishing run.

What do the WhalerCentral experts suggest for our combination?

Thank you

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My 1985 Evinrude 150 is mounted 1 hole up but needs to go up another hole.

I would to 2 holes up.

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Mark -

Moving the motor is a DIY with a set of hands task. You can use the trailer jack to change the transom height.You don't have to remove the engine. A search will give you the steps.

I gained 150 rpm's from each hole raised. Once remounted, retest and report.

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Thanks Phil. Yes, not difficult to change...my issue is time... the joys of being a business owner! Are you going to get another Whaler?

Joe: What prop are you running on your boat?

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I am running an OMC 17" pitch.

My 1985 motor has been detuned slightly (thicker head gasket) so it could use regular octane gas instead of the higher octane originally called for in the manual.
I am not sure about the 1986 model Johnson.

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I owned the same boat, same motor and same propeller for many years. That boat should be good for 45 MPH so if you are only hitting 37 MPH lightly loaded, something is wrong, and not just the motor mounting height.

My 150s (I had a 1983 and a 1990, both virtually identical) were mounted one hole up back in 1983. I am sure yours could be another hole higher even with the old SST II propeller (two holes up).

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Thanks Tom.

I suspected the same, so I'm going to have a good look at my engine control cables, as I just installed new xTreme cables. Perhaps I do not have them adjusted correctly to get WOT.

I will confirm full throttle opening, and raise the motor two holes and will report my findings.

Joe,

I was not aware of the fuel requirement. I'll fill with better fuel next time as well.


Cheers

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Mark,

What does your owners manual specify for octane requirements?
Your 1986 is probably different then my 1985.

My 1985 required 93 Octane leaded fuel.
In order for me to run unleaded Regular fuel, the motor had a service bulletin to change the head gasket.

Service Bulletin
This engine has been modified to run on 86 AKI Unleaded Fuel
Outboard Bulletin #2155

I have 3 props that I have tested.
The 17" pitch seems to work the best for my boat/motor combination and how I use the boat.
If I remember correctly, I am getting around 5200 RPM at WOT.
Raising my motor 1 more hole (2 holes up) should give me another 150 RPM.

Props
15 1/ 2 x 15 #391535
15 x 17 #391200
14 1/ 2 x 19 #389924

I would like to try something like the Viper 17" someday but haven't gotten around to buying one.

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Hi Joe,

I don't have an owners manual for the engine. Maybe I can locate on online somewhere.

Do you recall what your top speed is with the 17" prop?

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I am not a speed freak so I rarely go to full throttle.

If I remember correctly, I get around 40 to 42 depending on load and conditions and that is in fresh water.

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Thanks Joe.

I am a bit of a speed nut, but not so much for the boat. I just want to get it set up correctly based upon the WOT recommendations.

One more question: The notation about the modification for unleaded: Is that a decal on your motor or just a note added to your manual?

thank you

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It was a Service Bulletin sent to dealers back then.

A dealer serviced this motor back then and performed the Service Bulletin.
The motor has a sticker on it with the Service Bulletin number.

The sticker says this:
This engine has been modified to run on 86 AKI Unleaded Fuel
Outboard Bulletin #2155

All this is is a thicker head gasket which lowers the compression.
Basically a detuned 150 hp which I would be (guessing) 145 hp?

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Thanks for the thorough explanation Joe

I'll look for the decal on ours. Cheers

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I made some time to work on the boat tonight. I raised the engine from the lowest position to the 2 holes up position.

I also checked my throttle cable, and confirmed I'm getting WOT.

I'll be on the water again the weekend, so will report on how she goes.

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I ran the boat on the weekend after raising the engine to the two-holes-up position. The boat handles much better now: It gets on to a plane much easier, with much less bow rise, and rides better as TRIM adjustments are more effective and noticable.

I did not get a legitimate WOT run as I did not have my GPS on board, but a brief burst indicates it was better, but is still not a 45mph boat.

The engine runs well, smooth with no vibration to speak of, but feels somewhat flat at higher RPM, so I suspect it has an issue of some sort. Seat of the pants feel is that it might be an ignition advance problem...as if it is not getting full advance at higher RPM. Regardless, we'll have to start with a compression test and go from there.

PS - There is no decal on the engine like the one on Joe's 1985 150.

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Mark,

It is always good to know the WOT RPM's when testing.

What was your WOT RPM on the tachometer?

On my 1985, the specs say 4500 to 5500

On my 1986 70 hp motors, it was 5000 to 6000

Not sure what your motor should run at and from your statement in post #1, you weren't sure either.
Might help to get that info so you know for sure your recommended WOT RPM's.

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I saw 4800 yesterday, but I wouldn't call it a true test.

Everything I find notes these V6 150 engines WOT range to be the same 4500-5500 through the 1990 model year.

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Yes, 4800 RPM is consistent with this motor not producing its full power.

Outboard ignition timing almost never ever goes out of whack unless somebody messes with it. Old outboards very commonly suffer carburetor trouble or ignition problems relating to the power packs or simply spark plugs.

I'd verify the motor is firing on all six cylinders. A V-6 running on only five cylinders will run just fine and sound smooth and normal but will generate only 80 percent of its full power.

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I installed a fresh set of spark plugs and checked things over, tightening all plug leads and so on.
Today, with two people, 1/2 tank of fuel. 45mph, 5000 rpm. Fresh water, 1100' elevation. I thought I'd see more revs, but the top speed was solid on 45mph (by GPS) in both directions. This boat is awesome!

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One fouled plug can make a big difference. Glad you found the trouble without too much trouble. I share your "Thumbs up" on your boat as I am also a new 18 Outrage owner having a great time with it. You probably have a few more mph left in it if you lower elevation. I have a 4 cyl. Yamaha 130 hp. two stroke that will do 44 mph (gps) one hole up.