75 Boat Motor

If you'll look on mercurys engine specs all the motors (75,90, 115) have the same displacement and none of those three are paired on the same boat so you can compare how fast they run. Therefore, I am pretty sure they are all the same besides the way its tuned or chipped. Is there any way to buy a chip to go from 90 to 115? These are all new fourstroke motors I am talking about.

You are mostly right, except it isn't a chip, it's an ECM, electronic control module. The only other difference on the new 4/S EFIs is the prop you will use. You can buy a 115 hp ECM from Mercury, at a cost of about $1350. Surprisingly, $1350 is almost exactly the difference in price between a 90 and a 115. Mercury didn't become #1 by being stupid.

I would add, that the reasoning behind offering different horsepower engines is to comply with USCG rating regulations, which in most, if not all areas of the US, makes it illegal to over power a pleasurecraft. Fortunately, here in Canada, hp ratings are treated as recommendations, not regulations. The only thing we have to worry about is dealing with the insurance company.

2010-03-21 06:03:27 by Micah Moffitt

Made from aluminum. LOA: 7,5 m; Beam: 2,5 m; Draught: 0,4 m; Displacement: 2000 kg; Cruise speed (with outboard motor Suzuki DF 300): 30 knots (50 ...

what kind and how much?

3 cylinder carbureted 2-stroke, one of the most reliable outboard motors ever made.

Any oil as long as it is "TCW3" certified. I use supertech from walmart.

If the VRO oiling system has been disconnected, mix the oil with the fuel in a 50:1 ratio - 1/3 cup per gallon, 1 pint per six gallons.

If the VRO is still hooked up, just keep the oil reservoir topped off.

Use only 87 octane gasoline - higher octanes just lead to less complete burn.

Use only champion QL77JC4 gapped at .030 - not just a personal brand preference, johnnyrudes really do run better with champs.

Never start the engine without supplying water to the lower unit - 45 seconds of dry running will damage the water pump impeller.

Never rev the engine over 1500 or so (except as needed to warm up a cold engine) without the lower unit submerged -- it needs backpressure on the exhaust to avoid thermal runaway.

If you don't know the age of the water pump impeller, or if its more than two years, change it now - fairly simple operation but the downside of pump failure is catastrophic.

Just a little bit of care is all it needs, it'll still be running long after we're gone.

Have fun!

2008-06-13 10:24:03 by Someone_Smart

Price: $822.53 $699.66

24 volts of power, 75 pounds of peak thrust
Built-in battery indicator includes four levels of charge data to maximize fishing time
3-year manufacturer's warranty

not always, but most often outboard powered boats dont have a built in tank.
its possible the tank is no longer with the boat, its possible the fuel hose isnt either.

look for a 3/8" fuel hose, probably has a primer bulb in the middle of the line.

2010-06-19 11:42:20 by Tamara C

Decorative collectible
Original vintage magazine advertisement print
Unique gift

Also how many MPG do party boats get? The ones that could carry 50 fisherman. I know that the wind and travel speed play a factor, so let's say normal wind and traveling speed.

5-7 MPG, moderately loaded (4-600lb) at 2,000 rpm. My best guess. Tell me if I'm off.

2007-06-05 13:53:40 by mac

I want to find the best size and pitch to use for general boating, pulling tubes, but also fishing. I use the boat usually between 5000 to 6000ft elevation.

for speed a three blade. for load a four blade. 17 pitch, but your manual will say whats required.

2009-05-24 10:14:28 by Sam