2012 Tohatsu 6hp?

May 23, 2016
1,014
Catalina 22 #12502 BSC
Troops....going to look at a "lightly used" 2012 Tohatsu 6hp 20" long shaft next week being sold locally. Hasn't been used in 2 years, comes w/tank and stand for $500.

On the surface seems like a great deal if it runs fine. So, other than the obvious (tank testing), a few questions:

Anything notoriously problematic with that model/vintage?
Anything specifically I should be looking at/checking for?
Any suggested maintenance (by me) that should be done b4 putting it in service?

Thx in advance,
Ron
 
Nov 26, 2012
1,525
Hunter 34 Berkeley
I had a 2006 version. It’s not a great engine but it did the job. The big issue was ethanol. Very susceptible to ethanol problems. Ran for about 45 min on a freshly cleaned out carb before gumming up and quitting. 2006 was the beginning of the ethanol era so mine did not have ethanol resistance fuel lines. I assume the 2012 does.
 
Dec 19, 2006
5,731
Hunter 36 Punta Gorda
Most outboards have problems with Ethanol and hand. 2002 Yamaha 2 stroke
always stop running when needed it the most and rebuilt the carb and started using Ethanol free
gas and added Seafoam every tank and always ran great.
Nick
 
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Mar 20, 2015
2,253
C&C 30 Mk1 Silver Harbour, Lake Winnipeg
Very susceptible to ethanol problems.
Like ANY other small engine.
Use high octane fuel without ethanol.

I suspect that the 2012 is the same as the 2018.
If it was used on a sailboat, it will likely have almost no hours on it.
Only common complaint I've heard is about the friction system for the tiller.

$500 seems a great price. 20 year old, worn out outboards sell for that were I live.
@Gene Neill posted recently about some shaft play he had on his motor, but I've not seen that mentioned online before.
 
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Sailm8

.
Feb 21, 2008
1,713
Hunter 29.5 Punta Gorda
I have 1996 5hp. It hates ethanol and the fuel plug that goes from the hose to the engine male mounted on the engine is proprietary. It looks just like the ones hanging on the hook at the boat store but something is different. Motor runs great and has a zillion hours on it.
 
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Sep 30, 2013
3,291
1988 Catalina 22 central Florida
If it starts promptly and runs smoothly I would probably jump on it. Change the motor oil and lower unit oil. Run some Sea Foam through it just for luck.

From what I have been able to gather, impellers on these motors are such a PITA no one seems to change them preemptively. But on the other hand, they seem to last very well.
 
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May 24, 2004
6,790
CC 30 South Florida
If it has not been used in two years it is likely that the carburetor may be fouled. The Price is right and even if you have to purchase a new carburetor for a 20" shaft it will be a good price. Tohatsu/Nissan/Mecury all come from the same manufacturer.
 
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May 23, 2016
1,014
Catalina 22 #12502 BSC
If it starts promptly and runs smoothly I would probably jump on it. Change the motor oil and lower unit oil. Run some Sea Foam through it just for luck.

From what I have been able to gather, impellers on these motors are such a PITA no one seems to change them preemptively. But on the other hand, they seem to last very well.
all good advice guys...thx!

regarding impeller changeout, do-able, but clearly a PITA:
 
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Jul 27, 2011
4,530
Bavaria 38E Alamitos Bay
Like ANY other small engine.
Use high octane fuel without ethanol.
The last time I took my 5-hp Tohatsu in for maintenance, a couple of weeks ago, the guy advised not to use high octane b/c it causes the engine to run hot. Right now I'm running on EtOH-free formula @ 96 octane but w/no sign of running hot.
 
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Mar 20, 2015
2,253
C&C 30 Mk1 Silver Harbour, Lake Winnipeg
The last time I took my 5-hp Tohatsu in for maintenance, a couple of weeks ago, the guy advised not to use high octane b/c it causes the engine to run hot.
I called the dealer I bought the motor from, and Tohatsu directly, when I bought the motor.
They both recommended using non-ethanol high octane, and to use a fuel stabilizer that doesn't contain alcohol.

The owners manual specs:
"Unleaded Regular Gasoline : R+M/2: 87 or higher RON: 91 or higher"

The dealer specifically said not to use Sea Foam as a stabilizer since it has isopropanol (alcohol) in it. Ok for cleaning use, but not for a stabilizer.
https://seafoamsales.com/wp-content/uploads/2017/01/Sea-Foam-Motor-Treatment-SDS-v20161205-ENG.pdf


In Canada, you can buy 87, 89, 91, 94 at a gas station, so that leaves 91 and 94.

Alas, even some 91 and 94 in Canada now has Ethanol in it.
I'm lucky in that my Co-op station has 91 without ethanol :)

Maybe he was refering to the higher octane racing fuel that some people specially source and use ?

OTOH he may have been telling you handed down BS.
Some automotive techs we hire, pass on all sorts of BS to each other without technical info to back it up.
I suspect it all starts with some old guy passing on outdated technical info, that applied to products made when they were young or that they learned from someone long dead.

As you say, 96 is working fine from your experience.

When in doubt, ask the people who make the thing.
 
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Sep 30, 2013
3,291
1988 Catalina 22 central Florida
all good advice guys...thx!

regarding impeller changeout, do-able, but clearly a PITA:
That is a great video! I saved it for future reference. I'll need it by and by!

As for octane ... my manual states: "US and Canada - having a posted pump octane rating of 87 (R+M)/2 minimum. Premium gasoline (92 [R+M]/2 octane) is also acceptable." It goes on to say "The fuel system components on your TOHATSU engine will withstand up to 10% alcohol in the gasoline".

SHAME SHAME SHAME on Tohatsu for that last part. Obviously they know better. I have no choice but to conclude they value a brisk replacement-parts business more than a reputation for trouble-free operation.
 
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May 23, 2016
1,014
Catalina 22 #12502 BSC
I try to run whatever non-ethanol is available in these parts, usually higher octane (not sure which), in the outboard and all other small engines (lawnmower, chainsaw, weedwhacker, etc.)

Gene, yea, that impeller video is good, but 2 questions....what goop is he using (the white stuff), guessing lithium grease?...AND I didn't see him using any of those numerous gaskets from that parts package....???
 
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Mikem

.
Dec 20, 2009
753
Hunter 466 Bremerton
I had a 5hp 2 stroke Tohatsu. Always used ethanol free gas. Flushed motor with fresh water after every use. Even after months of non use it started first or second pull. Just sold it for $500 after having it for 19 years. Point is I think Tohatsu is a good brand.
 

Gunni

.
Mar 16, 2010
5,937
Beneteau 411 Oceanis Annapolis
The last time I took my 5-hp Tohatsu in for maintenance, a couple of weeks ago, the guy advised not to use high octane b/c it causes the engine to run hot. Right now I'm running on EtOH-free formula @ 96 octane but w/no sign of running hot.
You likely won’t see any sign of heat damage from too high octane fuel until the engine loses power because your exhaust valves are burned up. High octane fuel simply has a higher ignition temp, it does nothing for your carburetor or stored fuel.
 
Mar 26, 2011
2,935
Corsair F-24 MK I Deale, MD
I've been running e-10 without trouble since the beginning:
  • Close the tank vent when not in use. Every time.
  • Top it off.
  • If it is an installed tank, use a silica gel drier to keep it dry.
  • Use a good anti-corrosion additive, such as Seafoam, Merc Quick Store, or Biobor EB. Every time. Some are snake oil, some don't do much, but these were impressive in the lab and field.
I dislike ethanol on ploitical grounds (it isn't green), but functionally it's not a big deal. Just learn the new rules. Keep it dry.

Honestly, I had most of my outboard problems pre-ethanol. A few years of learning, but few problems since then. I had a few old motors (lawn and outboard) die from non-compatible components, but that is a thing of the past for most of us. And yes, the high octane-is-better thing is pure myth. 35 years as a refinery chem engr.
 
Sep 30, 2013
3,291
1988 Catalina 22 central Florida
I've been running e-10 without trouble since the beginning:
  • Close the tank vent when not in use. Every time.
  • Top it off.
  • If it is an installed tank, use a silica gel drier to keep it dry.
  • Use a good anti-corrosion additive, such as Seafoam, Merc Quick Store, or Biobor EB. Every time. Some are snake oil, some don't do much, but these were impressive in the lab and field.
I dislike ethanol on political grounds (it isn't green), but functionally it's not a big deal. Just learn the new rules.

Why not just buy uncontaminated fuel?
 
Mar 20, 2015
2,253
C&C 30 Mk1 Silver Harbour, Lake Winnipeg
what goop is he using (the white stuff), guessing lithium grease?...AND I didn't see him using any of those numerous gaskets from that parts package....???
That looks like a normal impeller swap for many outboards to me. Not a PITA really.
Ever since I fixed a friend's motor, I get sucked in to doing repairs for others now.
I use a tiny amount of silicone base lube when installing a new impeller like I would when using assembly lube for an automotive engine rebuild. If he is using lube in that video, I have no idea why he put it all over the gasket mating surfaces.

Depending on the kit, you won't need all the gaskets.
One shot in the video shows gaskets and the impeller plate which you don't usually replace unless you are taking the lower pump housing out due to the need for additional repairs.

I've pulled a apart a few for an impeller change and found they had pump damage. So I order a complete kit that includes an impeller, gaskets, impeller plate and housings, and just an impeller.
I then use one or the other. Saves me time having everything possible ready to go.
The goofy thing is, the impellers in the aftermarket kits seem not a well made as the aftermarket standalone impellers, so I have mixed an matched.
YMMV. I suspect that may be due to the suppliers my local outboard parts place uses.
 
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Aug 22, 2017
1,608
Hunter 26.5 West Palm Beach
I also prefer to use silicone based grease on rubber parts. Silicone plays well with rubber. Some other lubes do not.

Some guys grease their gaskets. Some guys soak them in oil overnight. Both these measures are attempts to make them easier to remove the next time you take the thing apart. Most guys I know put them on dry. Guys that use gasket cement on everything should be keel hauled.

Some guys run hi-test gas because that is what is available near them that does not have ethanol in it.

It is my understanding that high test is beneficial when you run high compression. Today's motors generally do not need it.

Ethanol fuel is fine if you use it up & don't let it sit in the fuel system. If it sits in an older fuel system with older formula rubber parts, then the rubber degrades quickly. If it sits in any fuel system that is exposed to moist air, then the moisture will bind with the ethanol over time & form a goop that causes trouble.