Tohatsu 50 D alarm

[Dawgfish]

darn buzzer is STILL going off for my motor @ just over 3000 rpm, this is after I've replaced the impeller, thermostat, water exaust line and opened the hole the line goes thru so as not to constrict the flow. I check the forum and didnt see anything for this , does anyone have any experience with this kinda thing happening? What the heck am I missing!! Any advice would be MUCH apreciated!!

[gyroplanes]

I have never had my alarm go off, so I am not well versed on this.
I thought the alarm was for "low oil". Maybe it's time to re-read my manual?

[133bhp]

Are getting decent flow from the check and idle port? Changed make of two stroke oil? messed around with timing/other?

Assuming all above is well I'd be checking the temp sensor is okay, else for running lean.

[Dawgfish]

its been my experience that 2 strokes have no timing. guess ill be checking that sensor....not sure how yet but its gotta be done....thanks fellas!

[Hamin' X]

its been my experience that 2 strokes have no timing.

Interesting: I wonder how they get the spark to the spark plug at the precise instant that it is needed for best combustion?

~Rich

[Bill McClure]

Is it fuel injected or carbureted? Do you have the owner's manual?

[133bhp]

its been my experience that 2 strokes have no timing. guess ill be checking that sensor....not sure how yet but its gotta be done....thanks fellas!

Think your thinking of cam timning? - either way, have a look, you'll see a timing link from carbs.

temp = check continity with a multimeter.

check t stat?

head gasket?

need to read the manual

[Dawgfish]

im gonna b testing the temp sensor which i finally found in a tohatsu parts book pdf , the manuel is good and all but as far as specifics go it specifically says take to a dealer a lot. Im fairly handy with tools & blueprints/schematics , problem is the details required to test specific tolerances are not mentioned in the manuel.
Im guessing that the temp sensor is normally open until a specific(?) temp is atained....then its suposed to allow a specific(?) amount of volts/amps(?) thru to the buzzer.
the motor smokes decent enough for a two stroke when starting, but the oil tank is still pretty full after 2.5 tanks o gas.no air in the oil line. no oil light burnin when it alarms.wonderin if the oil pump exit will squirt oil if i pop off the exit hose and turn the motor over...( to check if pump is still ok)
no head gasket leaks.
timing....ya 2 strokes has timing....no chain like 4 stroke where it needs constant attention. its just a magnetic pickup and cam based like ol boy mentioned, not something that needs messed with typically after the factory has it set unless ya go play with the stator or cam etc....
seems like the motor dont gain but 1-2 mph between 2000 &3000 rpm , it does get reeeaaallly loud at that point. maxed her out @ a smokin 9mph.....full ballast medium cargo. thought she should do better .
tech manuals are hi dollar and out of the question for now unless anyone knows where to find a free download ?not the regular manuel or the parts manuel i already have...
thanks for tryin to help all! got me brain a goin good...

[Bill McClure]

Hey Dawgfish,

The reason I ask if your engine is carb or fuel injected is the alarm systems are different for the two. According to the service manual for the carb model, the horn will sound and the engine only run at 3000 RPM max if it thinks it's overheating, low on oil, or not circulating enough water. The injected model has a much more sophisticated warning system that will tell you more information by a series of beeps. The owner's manuals are on the net for free. The service manual is available from Blue Water Yachts for about $50. It's well worth it for the troubleshooting flowcharts alone. The Clymer and Haynes manuals may be available at your local library, but I find them too general to be much help. They cover too many models. It's probably something basic, so do the simple things first, before you tear your engine apart.

Good luck.

Bill

[133bhp]

workshop manual

http://www.mediafire.com/?ofdp88a2ytnq5x1

[Dawgfish]

thanks for the tip on the BWY manuel, your post was very good info, the moderators here should make it a highlight . tohatsu wants a lot more for theirs....its carburated motor.
looked at the sensor but no way to tell without specs . tryin to download the mediafire manuel ol boy posted....could be a while b4 its done..
its a reeaallyy big pdf...

[Chinook]

I set off an alarm on my previous motor, a 50 hp Nissan TLDI. The alarm started when I ran above 7 knots, but quit when I slowed down. My problem ended up being a curled edge on one blade of my prop. Apparently I hit a piece of partially submerged woody debris and bent the prop. This threw things out of balance, and resulted in an alarm. After replacing the prop with my spare, the noise quit and never returned. Based on this experience, you might want to inspect your prop, to see if anything has thrown it out of balance.

[Tomfoolery]

darn buzzer is STILL going off for my motor @ just over 3000 rpm, this is after I've replaced the impeller, thermostat, water exaust line and opened the hole the line goes thru so as not to constrict the flow.

You may have stated this in another thread, but can the engine achieve rated WOT speed with the prop and boat as you normally use it? If it's lugging from being overpropped, it may be running hot, even at less than WOT.

[Dawgfish]

thanks for the link to the tohatsu pdf! excellent download!!!
between that and my manuel and my parts list (all pdf) i should get a grip on this .....

[Dawgfish]

I set off an alarm on my previous motor, a 50 hp Nissan TLDI. The alarm started when I ran above 7 knots, but quit when I slowed down. My problem ended up being a curled edge on one blade of my prop. Apparently I hit a piece of partially submerged woody debris and bent the prop. This threw things out of balance, and resulted in an alarm. After replacing the prop with my spare, the noise quit and never returned. Based on this experience, you might want to inspect your prop, to see if anything has thrown it out of balance.

just so happens there IS a slight curl to one of my prop blades....i didnt think it would be a problem but its worth a try at this point!