50hp Tohatsu dies @ full throttle

[shepnuts]

My 50hp Tohatsu ran fine sat morning between 4800 and 5000 rpms. we fished an area for about two hours, and on the way out it died. It died so abruptly that at first it sounded like it just siezed up. it started and got up again, and died at high rpms. we ran the boat for the rest of the day at about 4000 rpms and it ran perfectly fine. A week ago i ran a carb cleaner though it, changed filters, plugs, water pump kit. What is the problem? Did i possibly create this problem then?

the engine is a 01' H50D2.

 

[TOHATSU GURU]

Re: 50hp Tohatsu dies @ full throttle

It really could be anything at this point. Do a compression check, check for fire on the plugs and check your gear oil.

 

[coastalcruiser]

Re: 50hp Tohatsu dies @ full throttle

change the fuel filter for $1.50 clean the gas tank 20c for a spray paint filter take the carb off and rinse out the float bowl with carb cleaner, then bleed the float bowl. imho i bet it's dirt

 

[shepnuts]

Re: 50hp Tohatsu dies @ full throttle

change the fuel filter for $1.50 clean the gas tank 20c for a spray paint filter take the carb off and rinse out the float bowl with carb cleaner, then bleed the float bowl. imho i bet it's dirt

Thank you for your help. What is it exactly that I need to clean the fuel tank?

 

[coastalcruiser]

Re: 50hp Tohatsu dies @ full throttle

took a spray paint filter, they sell them at the auto parts store also where I got the gas filter the old filter looked dirty so as a test I blew though it, then the new one. new one was easyer now that's high tech!
I used another gas can and a funnel that fits the cone paint filter. just poured it back and forth a few times, there was lot's of crap in the filter after I finished

 

[Seabay]

Re: 50hp Tohatsu dies @ full throttle

I had a similar problem with my 1993 50D above 4500RPM where the warning buzzer would sound while it was happening and as soon as I lowered the RPM the buzzer would stop. The water pump stream would also stop over 4500RPM. The problem was a head gasket leak between the combustion chamber and water jacket blowing cooling water out of the power head. It may be solved by retorking the head bolts.
I found some the head bolts would not turn so I removed all the bolts and replaced the head gaskets. Three of the small bolts snapped when I removed them. I was able to remove 2 of the 3 snapped bolts and had a motorcycle shop drill and tap the one I could not remove. I replaced the small bolts with stainless steel bolts and used an aluminum based, high temperature, thread compound on all bolts. The small bolts hold the water jacket cover to the head. The large bolts hold the head to the engine block. You may be able to replace just the main head gasket by just removing the large bolts. Plan to spend a lot of time removing to old head gasket. It is tough to remove. My 50D is used in salt water but I run it in fresh water at the end every day I use it.

 

[coastalcruiser]

Re: 50hp Tohatsu dies @ full throttle

it was water in the fuel
cure? water seperating fuel filter

 

[holidaier]

Re: 50hp Tohatsu dies @ full throttle

I went to fill my fuel tank at my fav gas station.they were out of marine fuel so I filled with regular. Out on the water my 2008 90HP.Tohatsu died at hi RPM.To make long story short turns out the fuel I was using was 87 octane.I immediately swiched to other tank(92 octane)problem solved .Hope this helps.