Hello everyone. My competent marina shop is unable to keep my 2010 Tohatsu 6 hp 4 stroke engine running consistently on my 25 Cape Dory sailboat. Carbs rebuilt, non ethenol gas used, run till empty each time. I get about 8 uses of leaving and entering the marina before it acts up. I am even willing to buy another new engine just to have reliability but local mechanics say all these small outboards are having problems. One item with my engine is it is not used that often. It sits for 3 or 4 weeks at a time. I can't get an answer from local mechanics about what else to do or even a suggestion on a different engine. The engine quit 2 weeks ago, I sailed into the marina and was so frustrated I told the marina, "Just yank the boat and put it on land" and I would deal with it later. As it turned out, I was on land in MD for Sandy so it was not all bad.
Auxiliary Outboard Engines
- Thread starter draymond
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Been there, done all that. LEARNED THE HARD WAY.
Do not run it dry.
My dad taught me to run OB's dry and I followed that for 60 years till I bought a race boat with a Merc 4cy 6. Carb bowl is such that about a teaspoon of gas remains after you run it dry. That teaspoon evaporates leaving gunk even with 100% gas.
If you are a purist, you can rmove the cowl and loosen the drain screw each time you use the motor. otherwise, you just unplug the hose, leave the bowl full and fire it up, even after a month. No air in bowl, no evaporation.
Do not run it dry.
My dad taught me to run OB's dry and I followed that for 60 years till I bought a race boat with a Merc 4cy 6. Carb bowl is such that about a teaspoon of gas remains after you run it dry. That teaspoon evaporates leaving gunk even with 100% gas.
If you are a purist, you can rmove the cowl and loosen the drain screw each time you use the motor. otherwise, you just unplug the hose, leave the bowl full and fire it up, even after a month. No air in bowl, no evaporation.
In the old days of two strokes, running dry left a nice coating of anti corroding oil on the carb parts .. Running dry on a 4 stroke leaves the carb parts stripped of any coating and leaves a little gasoline that has a BIG tendency to turn to gum, especially in the presence of aluminum and brass.. the materials of construction of most carburetors. I think Bill and Alec have the right answers.
I agree with the don't run dry and using the stablizer, but would also think about a filter and make sure you aren't using an older tank on it. The idle jets are really small and will clog easy.
We use a .....
...filter on our 9.8 HP Tohatsu and have had no problems to date. When I do run it dry at the end of our trips I then also remove the drain screw to get the last of the gas out. That just takes a minute to do.
More info on the filter here....
http://purplesagetradingpost.com/sumner/macgregor2/outside-36.html
Sum
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We use a .....
...filter on our 9.8 HP Tohatsu and have had no problems to date. When I do run it dry at the end of our trips I then also remove the drain screw to get the last of the gas out. That just takes a minute to do.
More info on the filter here....
http://purplesagetradingpost.com/sumner/macgregor2/outside-36.html
Sum
[FONT=Arial, sans-serif]============================[/FONT]
Our Endeavour 37
Our MacGregor 26-S Pages
Our Trips to Utah, Idaho, Canada, Florida
Mac-Venture Links
Thanks for the answers. Interesting. Bill if I am reading it right, you are saying to not run it dry? Leaving bowl full could help. If I understand that right, that makes sense also.
Thanks so far.
Dean Raymond
Thanks so far.
Dean Raymond
Addendum...Let's see 22 plus year old Nissan 8.....2 stroke
Let's see 22 plus year old Nissan 8.....2 stroke sometimes it sits up to a year or more at a time. I never run it dry. On second set of plugs. Original fuel filter on engine. Always use a in line Atwood filter on fuel tank with fresh fuel. Follow strict prepping proto calls before starting. Make sure hose connector is properly seated etc...Squeeze pump bulb just so.... set choke to first click. Then calmly pull cord. Usually starts first pull. If it does not start by second pull then I forgot something....like forgetting the kill switch clip. After it warms up a bit it runs like a banshee !!!
Sorry for the addendum..The first posting was from my I-Pod. More to the problem......I would switch to a smaller 3 gallon gas tank and new fuel hose with a in line filter. I bet that has been your problem all along. At least clean and check the tank you have. If any ethonol fuel or a caustic cleaning agent has ever been used in the line or tank it could have damaged the inner walls of your tank or old fuel line.
BTW....I have neighbor who has a old Nissan 4 stroke and he has had no issues. So its got to be a dirty fuel....damaged fuel line and gas tank problem.
Let's see 22 plus year old Nissan 8.....2 stroke sometimes it sits up to a year or more at a time. I never run it dry. On second set of plugs. Original fuel filter on engine. Always use a in line Atwood filter on fuel tank with fresh fuel. Follow strict prepping proto calls before starting. Make sure hose connector is properly seated etc...Squeeze pump bulb just so.... set choke to first click. Then calmly pull cord. Usually starts first pull. If it does not start by second pull then I forgot something....like forgetting the kill switch clip. After it warms up a bit it runs like a banshee !!!
Sorry for the addendum..The first posting was from my I-Pod. More to the problem......I would switch to a smaller 3 gallon gas tank and new fuel hose with a in line filter. I bet that has been your problem all along. At least clean and check the tank you have. If any ethonol fuel or a caustic cleaning agent has ever been used in the line or tank it could have damaged the inner walls of your tank or old fuel line.
BTW....I have neighbor who has a old Nissan 4 stroke and he has had no issues. So its got to be a dirty fuel....damaged fuel line and gas tank problem.
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I'd like to know what the mechanic does that corrects the problem. sounds like what you are doing is correct. are you using the same old gas tank? or you have a portable 6 gal tank that gets new fuel every few months.
Does it make a difference that it usually starts fine and starts acting up after running for a short while.?
Another culprit could be the fuel line.
Also, I'd take it to a different mechanic. More than likely the marina shop has one qualified mechanic and he has a couple of minimum wage helpers that work small jobs.
Also, I'd take it to a different mechanic. More than likely the marina shop has one qualified mechanic and he has a couple of minimum wage helpers that work small jobs.
Oh, and I have an '04 6hp Tohatsu and do not have problems with this motor. I'm one of many satisfied Tohatsu owners on SBO.
I knew I would find a glimmer of hope here from the collective. I plan on incorporating every suggestion so far.
We have a 1981 5 HP 2-stroke, and I can echo Kloudie's observations because last year out of a sense of duty I removed and disassembled the carb, and i found it clean as a whistle except for a thin film of 2-stroke oil. I only use ethanol-free gas, and allegedly 'premium' 2-stroke oil.
I'm also a fan of SeaFoam as a cleaning additive - I've used it on small 4-stroke motors with good results.
love seafoam. but its like stabil. maintenance additive.
when you say it runs for a short while...before it starts giving trouble.
-what's a short while? and is this still in Neutral? or after its warmed up and in Forward?
So many things.... air leaks are common and hard to diagnose. (swap fuel lines). fuel tank (swap). etc. but if it runs great after a 'cash injection' by your local mechanic, I'd like to know what he is doing different.
(basic carb rebuild?)
does this OB have thermostats? -they can also produce bad running conditions...
when you say it runs for a short while...before it starts giving trouble.
-what's a short while? and is this still in Neutral? or after its warmed up and in Forward?
So many things.... air leaks are common and hard to diagnose. (swap fuel lines). fuel tank (swap). etc. but if it runs great after a 'cash injection' by your local mechanic, I'd like to know what he is doing different.
(basic carb rebuild?)
does this OB have thermostats? -they can also produce bad running conditions...
Hey....I have a two stroke.... so I won't seriously comment, 'cause your question is about a four stroke, which we all know is a completely different animal.
However, overheating and fuel supply restriction may lead to some of the symptoms you mentioned. So, check the tank's vent, it may be clogged, and be aware of operating temp if you can. Maybe a quick shot of carb cleaner could help.
However, overheating and fuel supply restriction may lead to some of the symptoms you mentioned. So, check the tank's vent, it may be clogged, and be aware of operating temp if you can. Maybe a quick shot of carb cleaner could help.
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