The truth about Tohatsu 40hp tldi upgrade to a 50hp

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Chillax

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Hello,
I read on different sites from different people that a Tohatsu 40hp TLDI is identical to a 50hp except for the restriction plate in the air intake (trotle body), they all say that if you take the plate out the ecu will ajust itself. So a 40hp is a downtuned (restricted) 50hp.
I also read that dealers are taking these plates out on request when they sell a complete new motor. So there has to be atleast some truth in it.
Are there people here who have done this mod?

To give a engine more air (unrestricting) won't damage it right?
 
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pvanv

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

Wrong. It's a differently programmed ECU, among other things, such as a different throttle body. "They" are full of it.
 

Chillax

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

Wrong. "They" are full of it.

Thanks but are you sure? I mean there are numerous forums and site's where these claimes are made, these are all false?
If i look at part nr's and blueprints the engine's are the same except for maybe the ECU and trotlebody which the restriction plate is the only difference but i might be wrong.
These obsevations are all by sight and not by compairing the inside of the ECU or the trotlebody.

What will happen if i take the restriction plate out, and wy is it in there?
 
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Sea Rider

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

Restrictor plates, restricts HP full punch, works along ECU and throttle body as stated by Paul, being a certified Tohatsu tecnician knows his TLDI horses well. If you remove plate, probably the engine will not work efficiently as the ECU and throttle are not being compensated to match more air intake. If you try it, measure max rpm and GPS speed achieved at wot, test with and without restrictor plate and post results...


Happy Boating
 
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Chillax

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

This
 
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Chillax

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

Paul, being a certified Tohatsu tecnician knows.
Happy Boating

Without saying a bad thing about Paul or any other Tohatsu dealer or technician, the thing with these fine people is that THEY may (indirect) work for Tohatsu and the can't and don't want to de-value any of there products or promote this kind of info begause THEY are maybe not as objective as we think. (But i am mostly wrong:))
I did read a lot on racing forums but also some of the lake and swamp forums, here in europe where i am from i read it on greek and Dutch sites. There all wrong? Wy would they post it?
 
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Bronlonius

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

Paul, sea rider, and Elvin(tohatsu guru) have helped people with conversions on this site before, and even posted part numbers of the parts needed so people know exactly what they need to buy. There is not some kind of conspiracy here, read some of their posts about 9.9 to 15hp conversions. I fully trust their advice.
 

Sea Rider

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

Chillax,

The only way to know if by removing a restrictor plate you can convert a TLDI 40 into a 50 is removing it and testing for yourself. Assume you want to buy a TLDI engine, 40 & 50 have different prices, being the 50 more pricey, but wanting to save some cash going for the 40 and removing restrictor plate to have a 50, right ?

2 strokes engine conversions are way much simpler to upgrade, as all electrical and mechanical parts are same compared to TLDI which are computerized more sophisticated engines. Not saying they're all wrong, but has any one of them stated tech data about GPS max speed achieved at wot with and without restrictor plate ???

Happy Boating
 
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deejaycee_2000

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

I'm not sure about the TLDI, but with the M40C & M40D most definitely ....
 

pvanv

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

Thanks but are you sure? I mean there are numerous forums and site's where these claimes are made, these are all false?
If i look at part nr's and blueprints the engine's are the same except for maybe the ECU and trotlebody which the restriction plate is the only difference but i might be wrong.
These obsevations are all by sight and not by compairing the inside of the ECU or the trotlebody.

What will happen if i take the restriction plate out, and wy is it in there?

Yes, I am sure.
1: It's a different ECU: 3GF064010M, ENGINE CONTROL UNIT (ECU) 50B2 TLDI, $1653.75
2: There isn't any restrictor plate at all. Period. It's a different throttle body.

"They" are still wrong. The motors share a block, etc... But the parts that determine output are completely different.

If you swap out throttle bodies, the motor will run horribly. The programming of the ECU is curved to match the fluid dynamics of the throttle body.

BTW, We are independent dealerships, and don't mince words about motors, we are not employees of Tohatsu. Yes, we like those motors, and sell/service them, but we are not paid by Tohatsu in any manner.
 
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Chillax

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

The normal speed at WOT with the restrictor plate was 43-44kmph (27mph)

Today i pop't the restrictor plate out and tested the speed again and it went 55kmph (34mph )and had way many rpm's 6200 thats 350 to many so the limmiter was beeping. If i put another prop on there it wil hit prox 65+ (40+mph)
The engine runs great and the fuel consumption is still very economical.

So for all the peeps with this block, its true! whatever "THEY may say about it" these are the facts.

This is a 50hp!


This is the plate in the trotle body (copy from another tldi topic)
IMG_20130820_203725.jpg


This is the plate out of the trotle body (from my boat today)
IMG_20130820_141818.jpg
IMG_20130820_141848.jpg
IMG_20130820_141911.jpg
 
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pvanv

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

Assuming you have model MD40B2, is the label on your ECU 3GG09AA, or is it 3GF09AA?
Did you reset the TPS?
 
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Chillax

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

Its a MD40B from 2008 sold in the end of 2009. I did not reset anything.
 

deejaycee_2000

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

That is still slow, I get 65mph out of mine ;)
 

Chillax

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

That is still slow, I get 65mph out of mine ;)

Hehe yes there is a guy on youtube 50hptilller he also gets 63mph on some kind of john boat.

I have a Funyak 4.5 (14.8 tf) that weighs 200kg (440 lbs) with the same hull as a rib so maybe i will hit 45 - 50mph? I don't know, we have to find out. But my boat is a litle heavy'r then a cat or a alu boat i think.

This is my boat;
IMG_20130704_160516.jpg
IMG_20130820_125605.jpg
IMG_20130704_160611.jpg
IMG_20130820_154417.jpg
 
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pvanv

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

Its a MD40B from 2008 sold in the end of 2009. I did not reset anything.
So, based on Tohatsu parts that are rated for North America, if your serial number is 006249 or below, you should have been running an ECU labelled 3T402AC... or if it's 011601XC and up, it should be an ECU labelled 3Z403AA.

There are a lot of emissions differences (spell that as carbs, ECUs, and throttle bodies) among motors built for North America, Europe, and the rest of the world. Parts intended for the EU are typically not available through Tohatsu America.

Your motor is not of North American release, so those ECU numbers might be different. Likewise, the throttle bodies might be different for Europe.
 
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Chillax

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

There are a lot of emissions differences (spell that as carbs, ECUs, and throttle bodies) among motors built for North America, Europe, and the rest of the world. Parts intended for the EU are typically not available through Tohatsu America.

Your motor is not of North American release, so those ECU numbers might be different. Likewise, the throttle bodies might be different for Europe.


I dont think this plate only come's in EU models, i say this begause most of my info came from US sites.
Here are a couple of them:

http://forums.iboats.com/honda-toha...nissan-tldi-40hp-restrictor-plate-295162.html


Tohatsu 40HP TLDI Throttle Body Same as 50HP? (See Pics)

Boating Talk: Tohatsu 40 HP TLDI - SaltyCajun.com

But what you say about the emissions standards thats true but i don't think these engines are different. Just look at the topics and you see the same restrictor plate. The numbers on the Ecu might be different from each other but thats for economical reason only i think. But than again i mostly wrong.

The engine will get 6 or 7x more air than with the restrictor plate, the only thing i have to check is the outflow and another prop.

MD40B 3T4
The Serial ends with **4994XH
 
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MattFL

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

Maybe the throttle bodies have different part numbers because one comes with the plate installed, but they are otherwise the same?
 

Chillax

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Re: Tale or truth Tohatsu 40hp bump to a 50hp

Re: Tale or truth Tohatsu 40hp bump to a 50hp

Maybe the throttle bodies have different part numbers because one comes with the plate installed, but they are otherwise the same?

Thats what i think.



There isn't any restrictor plate at all. Period. It's a different throttle body.

Here is the restrictor plate in the trotlebody, both US and EU 40hp TLDI models have them.
IMG_20130822_094213.jpg
IMG_20130822_094223.jpg
IMG_20130822_094227.jpg
 
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TOHATSU GURU

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Re: The truth about Tohatsu 40hp tldi upgrade to a 50hp

The ECM is different from the 40 to the 50 and the throttle body is different as well. The engine will use more fuel and oil and since the calibration will be off for the RPM you run a risk for the power improvement. IE clogged injectors. I wouldn't do it and if you end up with a blown engine I would urge you to come back here and tell everyone about it. That might keep the next person who can't afford a new block from ruining theirs.
 
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