How To ID And Upgrade Tohatsu 9.9 To 15?

Tegervolgyi

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Feb 27, 2015
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Hello for Everyone!

I have a Tohatsu 9.9 model, and I'd like to upgrage it to 15 hp.
I read the whole topic, and I also checked the service manual. As far as I understand, the way how I can upgrade my engine, is depends on, which vesrion I have: ) 9.9C, 9.9 D, or 9.9 D2. But I don't know, how I can identify, which on is mine.
I took some pictures about it. Can somebody inform me, which model I have, and help me, what is right way for upgrade?

Thank you in advance
Tamas

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GA_Boater

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Welcome aboard.

Took the liberty to move your post from an older thread and start a new one for you.
 

Sea Rider

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Sep 20, 2008
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Looking at your picks, your's must be a late 9.9D model, has the old small fuel filter, brass nuts and timing rods compared to the ones that comes on newer 9.9D2 & 15D2 models.

Happy Boating
 
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Tegervolgyi

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Feb 27, 2015
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7
I checked for the modell name, but I didn't find any sticker, related to the model type. Maybe my english isn't strong enough to understand, what is "outter side pan". Did you mean the housing? I checked every part of the engine, and I found only the following things:
Motor code on the cylinder: 1TH0-027
Serial number: 79934

Is it enough to know, which version I have?

Thanks
Thomas
 

Tegervolgyi

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Feb 27, 2015
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I also checked the service manual, and I found that I have to change the

Throttle Cam to 3M3-63718-0
Adjust the height of link rod from 75mm to 78mm

And based on Sea Riders's answer, I have to set the ignition timing. Am I right?

Are theese parts are different for 9.9B or 9.9C etc. ?
Or If I buy this Cam, will it work with my engine?
 

Tegervolgyi

Cadet
Joined
Feb 27, 2015
Messages
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I have to correct myself, I sholud have 9.9B2 or 9.9D2 based on Tohastu site, becouse it is a 2-stroke engine :)
 

Tegervolgyi

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Feb 27, 2015
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I found the Throttle Cam for 15B2

362-63718-0 THROTTLE CAM
So it seems, the question is still, which model I have
9.9 B2 or 9.9 D2?
 

Sea Rider

Supreme Mariner
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Both engine models were updated to D2. U need part N? 3M3-637180 which is the newly updated 15 D2 code. Your posted code corresponds to an older 9.9B2 engine. Both engines are same 250 CC. some minor updates have been made to D2. 9.9 D2 & 15 D2 models are still under current Japan production. Both cams have different height angles.

Happy Boating
 

Tegervolgyi

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Feb 27, 2015
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Thank you, I ordered the cam today :)
As I read, I have to set the rod hight from 75 to 78mm, but on my pictures, it seems it is in the highest position. Do you know why? As I checked in the parts list, there is only 1rod, which is avaliable for 9.9 and 15hp models. Do you think that somebody cut the end of the rod or I have to order a longer one?
 

TOHATSU GURU

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Jul 22, 2004
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The only thing you have to do is change the cam. The 9.9 setting is the same as the 15. The only reason it would be different is if someone changed the adjustment because they did not now what they were doing.
 

Sea Rider

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There's a 3 deg + timing advance on the 15D2 with respect to a 9.9D and 5 deg with respect to 9.9D2, As we don't know your current model must visually check timing advance and go from there.

What you need to do is :

1-Change cam firstly,
2-Throttle grip fully to wot
3-Check if both mating surfaces line matches 25 deg mark on timing advance plate
4-If stopping at 22? must move plate to the right to match 25? Must play with upper stoppers to do so.
5-Check if carb has butterfly wide opened at 180 deg. when plate matches 25?
6-If not, must adjust cam roller height nut so roller stops at highest peak of cam. Don't over actuate roller against cam.

Ask if you get lost on the adjusting procedure.

Happy Boating
 

Tegervolgyi

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Feb 27, 2015
Messages
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Thank you guys for the realy usefull help!
I'll come back with the result when the cam will arrive.

Happy Boating
 

bfd378

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Mar 1, 2015
Messages
2
I just want my 9.9 to run. I'll worry about upgrading it later. When I bought it, the sticker with model & serial number was long gone. Called tohatsu & we came up with it being a D or D2, by him asking questions & me answering the best I could. I got a clymer manual from my local tohatsu repair guy, (B793) but the pictures it has of a carburetor for my motor are listed as a carb for a 40-140 hp motor.
Mine sparks, even ran for a while, but it raced like crazy & I hit the kill switch each time it fired up. Was going to pull the carb, disassemble & soak it, but the book says to use alcohol, not "caustic carb cleaner or hot tank" my fuel pump is on the right side of the block (if im behind it looking forward) again, book says that's a larger motor & mine should have an integral pump & carburetor. Either I have a frankenmotor, or it isn't a 9.9 according to this book.help?
 
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pvanv

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Apr 20, 2008
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6,500
1. That book is worthless, except as tinder for the woodstove, or as Elvin used to say, maybe a doorstop.
2. Get the correct Factory service manual from any Tohatsu/Nissan dealer (you can use the dealer finder from the Tohatsu website). The manual will be a combination manual for all the obsolete 1- and 2-cylinder 2-stroke motors, but will have the specifics for your precise motor.
3. Your throttle may have been wide open.
4. Yes, if you want to Properly clean the carb, you will need to remove it, Completely disassemble it, and soak for at least 4 hours at room temp in real carb dip (available in 1-gallon cans at the local auto parts house). References to cleaning in alcohol are to keep you out of a hot tank (used to boil out cast iron engine blocks), which would dissolve the aluminum carb.
5. The carb for a 9.9D2 looks like this: 002-21043-4_FIG04.JPG
 
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bfd378

Recruit
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Mar 1, 2015
Messages
2
I called tohatsu an hour ago, sent a photo. Turns out I have an m12a motor. It is at the repair shop now, & the price of the book is going to be taken off my bill. Kinda crossing my fingers that it'll run again. I broke the throttle cable link in the tiller the other night. Guess I'm going to try & save for a newer, less obsolete kicker for my boat. Thank you for your help though, pvanv.
the thing is so old tohatsu doesn't even have an owner's manual for it.
 
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