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Can someone with a small outboard pls check something for me


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Can someone with a small outboard please do a brief check of something for me.

I'm trying to fix my Tohatsu 9.8hp 2 stroke and I've got to the point where I can no longer remember what is normal.

Can you tell me what happens if you

1. put the motor in forward gear (engine out of the water and not running).

2. turn the propeller manually in a forward direction.

Does it turn the engine over, or does the prop just slip making a clacking or clicking noise somewhere inside ?


I would really appreciate this - I need my motor for summer fishing.



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as above, whats the issue that youre trying to fix?

I have a Tohatsu 15, I have never stated it any other way then using the cord, and its generally very easy to kick over.

I would imagine putting it in gear and trying to turn the prop would turn the motor but it should not be easy to turn, if its easy to turn it could possibly indicate low compression.

Good Luck with it.



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We are all left guessing until VOLITAN (Arron) surfaces - my 2c is he is trying to assess if he has the gear shift in the correct position after re-assembly.

So on that assumption ... Arron: If the engine is in gear you should not be able to turn the prop without significant force, if its in neutral you will hear the clicking when you spin the prop. But I am not sure how you would tell if you are in forward or reverse just by spinning the prop.

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Sorry for the non-response. I had to do a quick trip to the Central Coast.

I deliberately didn't mention what I was trying to fix because its a bit complicated and long-winded. I doubt most people would read a post that long and confusing as it would have been.

I had already diagnosed the problem as a gearbox issue, pulled out the gearbox, propshaft, water pump, driveshaft and gear shifter mechanisms. Then disassembled gears, clutch etc. The strange thing was I could find nothing wrong at all. The gears were like new, not even any wear surfaces. No broken or loose parts. Everything clean and no iron fillings or scale in oil. Pulled out a micrometer and measured - all tolerances were on the good side of factory specifications as recorded in the workshop manual.

Cleaned everything, renewed seals, reassembled and tested.

That's when the weird bit struck. With propeller removed and driveshaft locked rigid (thus isolating the issue to the gearbox, because neither motor nor propeller are in play), the resistance to forward twisting of the propshaft was close to zero when the motor was in forward gear. As the prop-shaft was rotated there was a loud clacking noise going on which I presume is the clutch dogs being pushed out of the forward gear on their tapered faces, then clicking back into position as forced by the clutch spring when the next depression on the forward gear comes around.

I couldn't remember whether that is normal or not. Looking at the design of the gearbox, it looks like it should happen (dogs have a bevel on the non-driven side) - but I don't remember it being like that before.

I just wanted someone to tell me how their motor behaved.

So I went to BCF on the Central Coast and looked at their motors. Their brand is Parson, but all small outboard motor gearboxes are pretty much the same.

Theirs didn't do the clicking thing at all.

So I took it down to Patonga Creek and attached it to an old boat I keep there on the bank.

It ran like a dream.

So it works for now. Its not worth taking it to an outboard repair place because I'd rather put the money towards a new motor. As a motor, this model is first class rubbish.


Edited by Volitan
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Hi Aaron

With gearbox off power head and engaging either gear you should be able to rotate driveshaft or prop shaft and see the other shaft turning freely. Ratios between input to output bevel gears are close, so you would not have that much of resistance between the two shafts.

Have the shim washers gone back in correctly, something has gone together tight.

Good luck.

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