1989 40hp tohatsu issue

[oxbeast1210]

Re: 1989 40hp tohatsu issue

Yes my wife is my favorite person to take so that's not a big deal lol

The buttery fly does open to 180 degrees. I do not know how to check the magneto . yesterday
I put the motor trim one hole further from the transom and set the smart tabs on the most resistance im going to see how it does when set up like this . I'm starting to worry that it may be waterlogged or something whats the best way to check >??

thank you

 

[Sea Rider]

Re: 1989 40hp tohatsu issue

You could have 180? butterfly with 20? timing instead of 180? with 25? timing. With engine off, place gear into forward, raise carb white roller with finger untill stops, throttle fully untill roller meets cam end, holding that position, check crankcase mating surface (midle line betwen both lids) to stop/point at 25? magneto timing line mark, if stops so, you're ok, if not will need to advance timing untill reaches 25?. Check pics. Both 30 & 40 needs 25? timing marks.

One issue that happened with a Tohatsu 40 was that after fine tunning the engine/boat/ at it's best took it's time to plane, found the problem to be that being a double hull boat, had to much water in it's interior, drained the water completely and the planing lag disappeared by magic. Check your hull if happens to be double, boats have cell foam inside hulls, if with water your hull will weight ton more...

If boat is on a trailer, secure front winch to hull's front d'ring, raise engine completely, remove hull water plug, raise trailer the higher will go, if with water will see how it exits, leave properly raised for a complete day at open space and in plain sun, sun does wondefull things.

Happy Boating

 

[oxbeast1210]

Re: 1989 40hp tohatsu issue

Thanks again searider here is what it looks like when i did what you said. It appears that the timing is in fact wrong, how does it look to you? Also what kind of issues can one expect from improper timing?
thanks

 

[oxbeast1210]

Re: 1989 40hp tohatsu issue

Can the timing cause issues with getting on plane?
thanks

 

[Sea Rider]

Re: 1989 40hp tohatsu issue

You should have 7 marks, seems you have 8 ? Definitely a bad timed engine will not develop it's full potential specially at wot and that means longer planing time. Carb and timing must work exactly as factory stated.

Other point to have into consideration, pic shows part *1 being an old model made from brass, if not lubed well ball joint cap *2 produces a groove wear where it meets with ball joint which gives excesive side play and bad timing too. Move magneto plate side to side by hand and check if there's slack in between, if so, replace both parts before advancing timing. New ball joint is stainless steel, state of the art much better. Grease them properly before assembling back. Magneto plate must not have side play of any kind to work properly along with carb. If the apparently scratch happens to be a real timing mark, you are definitely 10? off...

346052280M Ball Joint (*1)
3B7052430M Cap C Ball Joint (*2)

Happy Boating

 

[oxbeast1210]

Re: 1989 40hp tohatsu issue

Can you repost that pic and mark which is the 0? plate mark ? You should have 7 marks, seems you habe 8 ? Definitely a bad timed engine will not develop it's full potential specially at wot. Carb and timing must work exact.

Happy Boating

No water very dry its currently at 15 degrees
Thank u

 

[oxbeast1210]

Re: 1989 40hp tohatsu issue

No water very dry its currently at 15 degrees
Thank u

mine definitely has 8 marks not 7. .
Do you know somewhere that can explain
Timing for me ? I will order those parts you suggested too
Thank you

 

[TOHATSU GURU]

Re: 1989 40hp tohatsu issue

Call 214-420-6440 and ask for technical support.

 

[Sea Rider]

Re: 1989 40hp tohatsu issue

mine definitely has 8 marks not 7. .
Do you know somewhere that can explain
Timing for me ? I will order those parts you suggested too
Thank you

Not an issue if has 8 timing marks as long you know which one is 0? mark to start from there towards 25? mark. That engine is much older than the ones we import down here which has only 7 marks. First change the suggested parts then will look forward...

Happy Boating

 

[oxbeast1210]

Re: 1989 40hp tohatsu issue

I have adjusted it to be at 25 degree wot I have ordered the parts you suggested and will replace them when they get here
thank you.
Mr Guru If i cant get it after these parts I will definitely call what is the cost for that type of assistance?
thank you

 

[pvanv]

Re: 1989 40hp tohatsu issue

Tohatsu America does not charge for technical advice.

 

[Sea Rider]

Re: 1989 40hp tohatsu issue

If both parts happen to have excesive play, probably will need to re adjust 25? timing/mating surface properly again when new parts are installed.....

Happy Boating

 

[oxbeast1210]

Re: 1989 40hp tohatsu issue

What kind of performance difference can one expect if the timing was off by 10 degree?

 

[Sea Rider]

Re: 1989 40hp tohatsu issue

Less faster instant response at hole shot/wot to break initial hull inertia to plane combo faster...

Happy Boating

 

[oxbeast1210]

Re: 1989 40hp tohatsu issue

going in the morning wish me luck!!

 

[oxbeast1210]

Re: 1989 40hp tohatsu issue

Well took it out this morning I had the tilt out one hole and the trim tabs set to the hardest setting.
Motor definitely felt a lot stronger and boat got a plane a little faster . I'm going to adjust the motor back to the hole I've had most luck with and put the smart tabs back on middle setting and try again. I went alone today so that might have been the reason it felt better. But at the same the this was the first time I was able to get it on plane with just me onboard

 

[Sea Rider]

Re: 1989 40hp tohatsu issue

Have you changed suggested parts and advanced timing to 25? ? Or the smart tabs test was made as it was ?

Happy Boating

 

[oxbeast1210]

Re: 1989 40hp tohatsu issue

I'm still waiting on the parts but the ones on my motor are not very worn out. I did advance to 25 degrees and can feel the extra power. think once I move the motor down and adjust the tabs ill be where I need to be. Ill replace the parts soon as they get in
thanks

 

[oxbeast1210]

Re: 1989 40hp tohatsu issue

Well i ordered a new prop to see if it helps my issue if this doesn't help ill be re-powering i found a good deal on a 50 tohatsu in my area do you that that would make much of a difference?

 

[Sea Rider]

Re: 1989 40hp tohatsu issue

If it's a 2 strokes 50 HP Tohatsu, you'll be comparing a 700 CC 3 cylinder against a 500 CC 2 cylinder of the 40C, 200 CC more should make a difference. You could sell the 40C as second hand to be placed on lighter boats. Have you ordered same size/pitch ?

Happy Boating