1999 M40D2 Automixing

Greytfish

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This past weekend I added a 1999 M40D2 to my boat shed. It's a 2 stroke, it has carbs, and it's automoxing. The motor started before I bought it on Friday. On Sunday I tried to start it and it would not turn over. The gas in it is over a year old and I should have drained it out but didn't. I squeezed it into the engine about three times before I gave up. I figured if it started once it would again. Bad decision I guess. My battery is brand new and the bulb got firm when priming the engine. I left the boat at my camp, and before I came home, I unhooked the gas line and let the gas leak out of the carbs with the little screws at the bottom of the bowls. I couldn't reach the bottom bowl since it's so far down in the frame.

Question - will the motor start if I drain the gas tank, replace with ethanol free gas, and keep trying to start it until the new gas works its way into the motor?
Also, the oil tank is full of oil but suspect it's old as well. Does it go bad? Should I replace it?

Any advice is welcome!!
 

Greytfish

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Oh I would like to buy a service manual for it and would like to know a good place to buy one online. Guess I need the serial number to ensure to model number is correct?
 

Greytfish

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I mentioned above that the engine would not turn over ...... What I mean is that it would try crank but would not fire off and start running.
 

Greytfish

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This is the motor. Sorry for the side view. It was used by a snow bird a few times a year
 

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Sea Rider

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Some isues :

Assume OB has spark on all 3 cylinders ? If so mix 50:1 2 stroke oil and fresh fuel, could be E or non E one, if premium better. Remove plugs and squirt a small portion on each cylinder, put plugs back in and start OB electrically. Fuel should ignite and let fresh fuel pass through reed valves onto combustion chamber. How many amp bat are you currently using.

How old is that 2 strokes oil sittting in oil deposit ? If it's very old I would replace it for fresh one. Would suggest to read that 40 D2 Owner's Manual fully, there are some important issues regarding auto mixing procedures that you should know about before operating OB.

Happy Boating
 

Greytfish

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Sea Rider thanks! I will download the owners manual from Tohatsu and read it closely with regards to oil.

To answer your questions, I'm pretty sure the oil is old like over a year old. And on the battery, it's a Duracell marine 12v deep cycle battery with 500 crank amps and 75AH.
 

Greytfish

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I don't know if this matters, but I trailered the motor in the tilted up position with the lock engaged for about 2 hours.
 

Sea Rider

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About tilting OB while driving for 2 hours, who knows, next time before taking combo out of water disconnect OB fuel connector and let OB die of fuel starvation before trailering it with car.

Happy Boating
 

Greytfish

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I'm getting advised to remove the oil tank and bypass this system due to problems. Is this a good idea?
 

pvanv

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Tohatsu auto mixing is rock solid. Premixing is not necessary.

Flush out the entire fuel system. Make sure electric choke is working. Might need to clean carbs.
 
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Sea Rider

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Auto mixing oil dosification is way better, less oil ratio is used at low speeds than 50:1 oil ratio of the premix used at same slow speeds.

Happy Boating
 
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Greytfish

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Thanks guys!!! Worked like a charm. However I have air in the line leading from the oil filter to the motor, which makes me think it is not working. I have oil in the gas so I'm ok. I tried loosening the screw on top of the little oil pump like the manual says but that didn't seem to bleed the air out of that line. Maybe I needed to let more oil spill out of the top of the pump. Any way I figured the air pocket would work its way out once it started running. Any thoughts?
 

pvanv

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Never trailer with the motor tilted; you can damage the transom of the boat or brackets on the motor. Bleeding air from the automix system takes a fair amount of time. If you run with 50:1 premix in the tank while bleeding, you will be fine.
 

Greytfish

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Hey Braintrusts of all things Tohatsu,

I've taken the motor out two times since clearing out the carbs and it has performed nicely. I did have two new problems pop up...... 1. The clutch cable broke, and 2. It overheated, heard the alarm and then the motor decelerated itself. I just putted back to the landing after that. So I have some questions about these two problems.
1. Clutch cable - plan on replacing it and the throttle cable. My question is about the length I need to buy......I measured the length from the RC-across the deck to the hole where they emerge from under the deck-then to the motor to about where they will connect in the motor. The distance is about 10ft. HOWEVER, the current set of cables is about 14ft and had to be looped once before going into the motor. Is it ok to just buy the 10ft cables vs buying the 14 ft cables? I can't see why having a looped cable is a good idea.
2. Overheating - I'm pretty sure it's the water pump I doubt it's ever been replaced or if so only maybe once but certainly no regular maintenance. Watter only dribbles out at an idle and at high RPMs it's stronger but pretty weak. I have a water pump kit already and I have the service manual for the motor. Replacing the impleller seems easy enough, but replacing the gaskets and metal housing might be more challenging. Would you recommend this job for a weekend warrior? Buy the way, I tried this on my MD25A 4 stroke one time and I crushed the water tube and broke a bolt off in the motor trying to remove the pump housing. The Tohatsu mechanic that fixed it also told me that I didn't properly seat the steel impeller cup back into the rubber housing cover and that it had to be done just right for it to operate properly. I did manage not to lose the key however.

Any advice on these two problems would be appreciated!

Darren
 

Greytfish

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No Title

Here is a pic of where the cable broke
 

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Sea Rider

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Sometimes when the distance doesn't match steering wheel to outboard cable lenght usually go for larger remote cables and loops them as seen. This is the usual remote cable installation know how.

Mechanical Steering.jpg

Change complete water pump kit if having one, simple process. Take pics while dissassembling to assemble back same as seen on Rick's Restoration TV Show LOL!!

Is thermostat in good working order ? if rusted, corroded, extreme salty, change for a new one along thermo gasket.

Happy Boating
 
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pvanv

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Replace both cables. Put a loop in them so they flex when the motor turns port and starboard. The loop requires 3 or 4 feet additional.
Any owner should learn to do the water pump. Should be done every 3 years in cold clean fresh water; more often in silty/salt water. If the job seems beyond your skills, see a trusted mechanic.
 
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Greytfish

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I'm going to do these two jobs myself and just be careful. I have the water pump kit and will buy the cables from Tohatsu. Do you recommend that I use the consumables mentioned in the service manual? Ex. anerobic Gasket stuff (Locktite 512 I think), greases, gasket remover, etc.? I have no problem following the manual closely.

I also have a carb kit- floats, gaskets, etc. Are they more complicated than the water pump?
 

Sea Rider

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Doesn't have to be OEM materials as long complies with them. If carbs are working spot on, leave them along. Just change water pump kit, remote cables, thermo if shot.

Happy Boating
 
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