My Tohatsu 50

[gyroplanes]

Hi everyone,
I really worry about my motor. It makes such a racket at idle, in neutral. Underway, in fwd or rev, it's smooth.
I took this video of it after a 30 sec warm-up, it's in neutral and I'm working the little "aux" lever.
Any comments are appreciated (except about the scum around the motor well)
Tom, HAmmond Marina, Lake Michigan




http://www.youtube.com/watch?v=Z11-B-nTm6g

[Duane Dunn, Allegro]

Certainly not what my Tohatsu 50 sounded like at idle. Mine made none of that racket. Almost sounds like the firing order is wrong. I'd have a mechanic check it out.

[captronr]

Mine's never sounded like that. Mine runs a little rough on a cold start, but nothing as rough as yours.

Ron

[Capt Capsize]

My older (1997) Nissan DF50 used to run really rough, kind of like yours/ It improved with high octane gas. Mine has carbs, not fuel injected and I am at a high altitude, over 5000ft. I also found the throttle linkage on mine had a lot of play and some shimming helped, because the rough idle was amplified by the loose linkage. Good luck

[Newell]

Get several Nisson decals and place them over the Tohatsu stickers.

Serious, change out the plugs.

Newell
96X Fast Sunday Nisson 50D

[craiglaforce]

Mine has done the same thing, it was aIr leaking into the fuel line. Try replacing the quick connector at the gas tank, tightening all hose clamps etc and check for any sign of air getting in.

if that and new plugs doesn't help, shoot carb cleaner into the carb bowl drains. SHould fix it up. Good luck

[Rich Plumb]

I had a Nissan 50 on my X, and I agree with others here. The first thing to try is just change out the spark plugs. You have only three cylinders in the first place.

Good luck.

~~~~~~~~~~~~_/)~~~~~~~~~~~~~
Rich Plumb, Covington WA
S/V Chieftain, Morgan 462

[gyroplanes]

And all this time I thought I had 2 cylinders!

It runs very smooth at cruise and doesn't visibly smoke. It idles much better after prolonged running. Sounds like a lean situation at idle.

The smoke and banging around at idle are making me think I'm on the fuel tank with the older gas in it. I probably ought to eliminate low octane as a possibility before I dig into the motor.

The PO said he had it seviced and a new water pump installed by a dealer recently.

I like the idea of re-badging the motor to make it run smoother, but what brand runs the smoothest and makes the best power.
Maybe I should just paint it white to make it better?

[Duane Dunn, Allegro]

You may already know this, the Nissan 50's are made by Tohatsu. They were the exact same engine except for the stickers.

These Tohatsu 50's have a reputation of extreme durability, while they may run rough occasionally, they almost always still run. Not only are there 3 cylinders, there are 3 carbs, 3 coils, three of almost everything which keeps them going even if one of something fails.

[waternwaves]

When it is in the water.,

what is the max RPM,

I would definitely check the plugs/wires, seems that not all are combusting in sequence...

If you have decreased RPM at top speed, start checking the computer wiring under the cover, especially check for any jacket insulation damage and salt bridging. On the clear butt spliced connectors throughout the engine, check to see if they are blu/green with corrosion, replace any connectors that are corroded.

I have spent a fair amount of time babysitting Nissan/Tohatsu , Cant say that I love this engine. But generally it will get you home..... even if one of the spark plug wires is an open circuit......

But it wont get you home fast.

[Don T]

Hello,
Mine has always ran like that. Just sounds like it is loading up a bit. I didn't hear anything unusual but of course the audio quality is not so good. There is always a chance the timing rod / plate under the flywheel is frozen so it's running at full advance. My Tohatsu 50 doesn't start running smoothly until 1800 rpm under load. There are little misfires until then.

[SkiDeep2001]

Tom, my 98 Nissan 50 sounded similar so I put in new plugs and the idle smoothed out. Like Darren says, check your wiring also but new plugs may be all you need. Mine's set to 800 RPM idle which is a little high but it helped eliminate the slow idle shaking which I didn't feel was good for the motor so I'm OK with the higher idle speed. I just hope the higher shift speed won't cause trouble down the road, I don't notice any clunking. Once I engage F/R the RPM drops down slightly and the motor runs smooth. Rob

[bscott]

New gas and throw some SeaFoam into the tank. You might have some contamination in you idle circuit-new plugs are cheap.

Bob

[dlandersson]

Is there a Chicago-ara Macgregor dealer in order to show my boss aka wife a Macgregor 26?

Dave in Hammond

[kmclemore]

Mine sounded exactly like that, and it turned out to be fouled carbs... A thorough cleaning fixed it. This motor is EXTERMELY sensitive to bad gas... You MUST drain the petrol from the carbs if you intend to not use the boat for more than a week or so... Yes, I said week. Also, use petrol preservative in your tanks... Not the red stuff - that doesn't work for today's petrol... Use the green/blue stuff (enzymes)... This will help prevent the fuel going bad.