Nissan 6 HP 4 cycles

[Orca]

Well, the weather finally settled a bit here so I took the Nissan 6 HP extra long shaft (25 inch) down to the mooring today and installed it. I checked and it fits sideways in the lazarette just fine. I found that the top of the motor barely cleared the top of the lazarette which makes me wonder if the mounting board is higher than other boats as somebody previously reported 2 or three inches of clearance. I think I have less than 1/2 inch clearance.. I intend to visit Orca in the AM and motor around a bit. I think its a bit noisier at low speeds than the 8 HP I took out and it isn't as smooth because it is a single cylinder and the old engine was two cylinder. I'll report back on how it handles with the prop around 10 inches more underwater after I use it a bit.

Very Best, Ed

[Orca]

Well, the weather finally settled a bit here so I took the Nissan 6 HP extra long shaft (25 inch) down to the mooring today and installed it. I checked and it fits sideways in the lazarette just fine. I found that the top of the motor barely cleared the top of the lazarette which makes me wonder if the mounting board is higher than other boats as somebody previously reported 2 or three inches of clearance. I think I have less than 1/2 inch clearance.. I intend to visit Orca in the AM and motor around a bit. I think its a bit noisier at low speeds than the 8 HP I took out and it isn't as smooth because it is a single cylinder and the old engine was two cylinder. I'll report back on how it handles with the prop around 10 inches more underwater after I use it a bit.

Very Best, Ed

Hi: After using it a bit I can tell you the following. The 6 HP 4 cycle is quieter than my 8 hp 2 stroke Nissan but not quite as fast into the wind. It does seem to do something close to 6 knots when its calm (I'll have to wait a bit to try duing a slack tide as I rely on the GPS which showed a range of 4.8 to 6.5 knots over the ground). The clearance is less than 1/2 an inch on my boat and seems to touch the top of the lazarett when under load. The lazy rat buggered up the top of the motor a little so I now jimmy it open a little when running. My old motor was a 15 inch shaft. It had some issues in rough seas and was pretty much useless if a bigger person went up on the bow. For my money I think the 25" shaft is good insurance for some of the high chop that develops around here in the river mouths like the Kennebec where closely spaced, steep 5' or larger standing waves are a regular occurance . . . I suspect that 5" additional shaft would not be enough. The extra depth makes it a lot easier to back the boat down. The fuel economy is very good. After a few hours (mostly at 3/4 throttle or less) the little tank is still showing mostly full. I'm glad to see that the fuel connection on the motor has been reconfigured. I had to buy several of the old connections on the Nissan before I found one that worked.

Thanks, Ed

[Scott Galloway]

My Nissan 6 hp long shaft motor also has a clearance of about 1/23 inch. I use a Garhauer lifting davit to lift it into place. The Davis OB lifting strap that I use to lift the motor has a somewhat round cover that joins the two sections of the webbed straps. With that approximately 1 inch round addition added to the motor height, the lazarette barely closes and latches with some pressure, but then again, I don't normally latch the locker when under sail. Incidentally it was a great 10 to 12 knot sail out over the Submarine Canyon on Monterey Bay yesterday.

[Hull376]

To continue on with comments on the 6 hp four strokes all made by Tohatsu, I've had mine running since 2004 and have some comments on maintenance. Everyone knows by now that its a good idea to drain or run excess Ethanol 10% gas out of the carb if you aren't going to use the outboard every two weeks or so. Gas stabil is almost a must because the ethanol absorbs water. Over the years, I've found that the common reason my motor wouldn't start or idle well is bacause of clogged jets from fuel. In Houston, with 95 degree temps every day in the summer, it doesn't take long to evaporate all the fuel and leave the gunk behind in the carb. I've cured any problems by disassembling the carb and soaking in carb cleaner. I've found that the spray cans don't do a complete job. However, I recently found that hard starting and engine dying was because of an ignition problem---- not dirty carb issues. I used a spark tester and found I wasn't getting a spark on each pull of the starter roper. I got out the Tohatsu factory manual (the real deal which I purchased from Defender) and tested the resistance of the ignition coil, the exciter coil (which sits under the flywheel) and the pulser coil-- which is at the edge of the flywheel under the starter rope hole. Most of the coil resistance tests allow a plus or minus 20% reading from the factory spec, and still be good. But my exciter coil was off spec. The exciter coil generates the low voltage current, sends it to the CD unit (that little black box with all the wires leading to it). The CD unit stores this energy until its told by the pulser coil that its time to fire the plug. The CD then sends voltage to the ignition coil (roundish black epoxy coated coil connected to the spark plug wire) which then steps up the voltage to fire the plug. The factory resistance of the exciter is supposed to be 119 ohm plus or minus 20%. Mine was reading 78. So there was a developing short somewhere in that coil, and it wasn't generating enough voltage at low rpm or, most importantly, when I pulled on the starter rope! I put in a new coil (they are about $30) an now the motor starts on first or second pull-- like when it was new. The hardest part of this job was getting the flywheel off. You can read online on how to do this properly. You can mess up the flywheel and do some real damage if you don't use the right tools. With the right tools, its easy.

As you engine ages, and it starts getting harder to start and idles less reliably, check you coils. I didn't think modern coils failed very frequently, but my experience shows that they can and do.