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Tohatsu 30 hp sudden stop

4

4950cycle

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"I was testing my Tohasu 30 hp

"I was testing my Tohasu 30 hp today after some prop custumizing. It is an oldie. I believe she is from the early to mid eightys.It has a round not splined shaft with a shear pin. Heck, I can'teven get a prop with more than a 9 inch pitch for her anymore. The model #s start with 346..... With what I think is a B on the prop. Anyway, I was going full bore up the Withlacoochee river when all of a sudden she shut down with not even a sputter first. After attempting to restart her with no success I trolled to the boat ramp and drug her home. Just for kicks I pulled the pull start back at home and she took right off like new again. The see thrue fuel filter bowl was full of gas mix with no water in it. I figure the coil or CDI broke down after the motor was heated up ? Then after cool down it worked again ? Does my motor even have a CDI ? Should I test or do something before flying off on an unesessary tangant trying to fix something that isn't broken ? And if one of the ignition components are malfunctioning,wich one ? Any help would be greatly appreciated. Remember, she shut down all at once. John"
 
The guy at Internetoutboard sa

The guy at Internetoutboard said today that this motor was sold in early 1985 it is one of the few that have the old school shear shaft AND the newer CDI/coil all in one square unit on the (car) passenger side of the motor. This motor is real bad about not having any model #s. I emailed every # on the motor to Tohatsuamerica and they said non of them meant anything to them.
 
well internetoutboards aint th

well internetoutboards aint the brightest star in the sky the only tohatsu i have seen with a shear pin was an m8A
 
Then you must me very young an

Then you must me very young and a very dim star....Probably a red dwarf. All of the Tohatsu's before 1984 were shear pin type and the 3.5 hp and smaller still are.
 
"OK fellas lets not get in a p

"OK fellas lets not get in a pissin match here. I had stated what kind of ignition system the motor was equipt with. In light of that, What might be wrong with it reffering to my previous post ?"
 
"If its an ignition problem:

"If its an ignition problem:

Kill switch/stop button
Ignition switch/start button
Exciter coil
Trigger coil
CD module
Bad wire
Bad ground.

You have described an engine made in the last couple of months of production of the 30A2. That should make it an 84 or more likely, an 85."
 
Thank you so much for your hel

Thank you so much for your help in identifying my motor Guru. A 30A2 huh.. . Well now I'm sure to piss you off even though it makes me Happy Happy joy joy. Even though the motor shut down at full tilt without even a sputter. I decided to rule the fuel supply / carberater out anyway to keep me from going on my typical wild goose chase. The dog gone float needle hole had a piece of debris blocking it almost entirely. I guess the reason it started after I got home was because just enough gasmix trickled past the blockage to let it start briefly. And I even know what motor I have now. Thanks again Guru. PS I noticed that when I was trying to find a fuel pump diaphram that the Mariner diaphram looked identical to my Tohatsu. I know that some of the Mariners are made in Japan. Are the Japanese Mariners the same motor as Nissan / Tohatsu ? That sure would make it easier for me to find parts since the Japanese shut the supply of more than ten year old Tohatsu motor parts off.
 
"I'm happy for you. But yo

"I'm happy for you. But you point out the importance of troubleshooting the engine BEFORE you start worrying about getting a part.

Most of the Mariners were built by Tohatsu up until the early 90's when Tohatsu started producing them in 5 hp and down. Since then Tohatsu has now taken over production of most, if not all, of the 40 hp and down worldwide. Mariner is no longer sold in the U.S.(sometimes they show up in stores here anyway). Tohatsu still has parts for your model engine. There are a few items which are no longer available, but your engine is 25 years old so I wouldn't really fault them."
 
"I know, "Like the importa

"I know, "Like the important parts are not available". Like props, ignition parts ect. I know now they were made by Tohatsu but Is like a 1985 Mariner 30 hp the same exact (almost) engine as a Tohatsu 30 hp of the same year ? Or are there big variations ?"
 
"Nothing in common at all, as

"Nothing in common at all, as far as I know, as the Mariner was a Yamaha. Other than the exciter coil and trigger coil the other ignition parts are available on your engine. They are down to one prop pitch though..."
 
"I thought you said Mariner we

"I thought you said Mariner were Tohatsu ? And second, I hope exciter coils and trigger coils last a heck of long time then.Because I really love this little power house. It shoves my little 1962 Orlando clipper up the river at a breakneck speed.It can actually spook me a little with this reworked prop. AND I can actually work on it with pleasure.It's like a stinken push mower to work on."
 
charge coils usaully last a lo

charge coils usaully last a long time trigger coils never go bad or atleast we never changed one if you can still get ignition componet i would keep them around cause when the japs stop building the parts you aint going to get one unlike the old mercs proud owner of a mark 55
 
What was the Mark 55 ? My dad

What was the Mark 55 ? My dad had and old White Merc 22 hp I believe. On a 14 foot john I remember running what seemed as fast as the cars in the canal along side of Aligator Ally. We still laugh about that some time. And that was about 38 yrs. ago. Fast little Merc. PS. I forgot and replyed to your last post in my email instead of comming here and posting my reply.
 
"Meriner is a Mercury owned la

"Meriner is a Mercury owned label. Yamaha and Mercury both produced engines under that label starting in the late 70's. "Most of the Mariners were built by Tohatsu up until the early 90's when Tohatsu started producing them in 5 hp and down. Since then Tohatsu has now taken over production of most, if not all, of the 40 hp and down worldwide.""
 
"I have one last Maybe problem

"I have one last Maybe problem you might be able to shed some light on Guru. My water pump indicater hole only spits out a broken stream of water (spittering) while running. I pulled off the lower unit and took my water pump apart.It all checks out. The plate shows no wear yet,The impeller has no wear yet, the rubber is still alive,The paddles look like new. This is the same new water pump I put in a couple years ago. It only has a couple of 1 day trips on it. So next I think my indicater hole might be partially clogged. But that is not so because when I use the Tohatsu garden hose attachment it spits a solid stream with city water pressure doing the the work instead of the water pump. I have taken it out on a couple trips against my better judgment and it still has strong power. The reason I went is because there is plenty of water coming out of the center exhost port in the rear of the motor. Is that good enough ?"
 
I would think so. The pee indi

I would think so. The pee indicator is just a visual assurance that the pump is working. You probably have some build up in the block that is preventing the stream from peeing under impeller pressure as you have surmised. The majority of the water is zipping out through the prop. Did you put grease on the impeller by any chance?
 
If I remember correctly I beli

If I remember correctly I believe I put a little on the Impeller & plate for initial start up so it wouldn't spin dry for a minute. Don't tell me I screwed up Guru !
 
"You screwed up John. Take it

"You screwed up John. Take it back down and remove the grease......Unless it was a tiny amount it will prevent the pump from working properly. On ancient J & E engines it was a requirement, but on Jap engines(and Chryslers) it is a no, no. It may not make a difference on the pee tube output at this point."
 
the mark 55 was a 40 hp 4 cyli

the mark 55 was a 40 hp 4 cyliner probaly has only 30 in reality but its still pretty cool i put a little grease on all my impellers on assembly i havent had any probelms yet
 
Around what years was the Mark

Around what years was the Mark 5 made ? And I thought all Mercs where powerful in there class. And BTW how many impellers could one outboard have ?
 
the mark 5 i beeive it was 195

the mark 5 i beeive it was 1953-1955 they were quite powerful back in the day but the mark 55 got beat by a 50hp nissan in every catagory expcept idle quility i put the mark 55 on my jon boat goes about 30 put the 50 on my j14 carolina skiff the only engine i know that has more thant one impeller was the scott atwater bail o matic models i had one pretty neat pumped your boat out as it ran
 
"Hey Guru, I have a chance to

"Hey Guru, I have a chance to get a shop manual for a M35A manual for about $ 12 to my door. My motor is a M30 A2 according to you. Is the M35 in the 40 hp family or the M30 family of motors in those years ?"
 
You wouldn't happen to kno

You wouldn't happen to know where to get shear pins for this motor (M30A2) would you ? Internetoutboards doesn't have them. Ofcoarse they are a weird size. It messures around .225".Two marinas didn't have them so far. I bet sparkplugs will even be a wild goose chase with this motor LOL. Boy it is really turning into a DOOZY !
 
i doubt it im sure you could g

i doubt it im sure you could get them shear pin are they brass or stainless i make all mine its a lot cheaper find some stock in the diameter yours is and make your own as far as plugs they are probaly ngk whats the number on the plug im sure they still make them
 
"The problem is my prop has no

"The problem is my prop has no hub slippage. It is a straight drive prop. Therefore the shear pin absolutly must do its job and shear if the prop hits something. Otherwise the lower unit will take the blow. The problem is with 30 hp, Aluminum is to soft, Brass is to soft. I already tested them. So I need to make sure the stainless pin I get is a soft enough alloy to shear. If it holds tough in a bad prop hit it could waste my lower unit."
 
yeah but the 3.5 runs a stainl

yeah but the 3.5 runs a stainless pin i have a morph motor some guy built 5hp on a 3.5 mid i hit a rock the day and it sheared the stainless pin with out damaging the gear or the plastic prop so idk man i think you would be fine i mean was the old one made of if brass is too weak then it has to be stainless they dont run steel its even stronger if your old one is silver and dont attract a magnet its stainless alums way to soft
 
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