Tohatsu 4hp to 6hp mod & other mods I've made to my outboard (2019 Tohatsu 4hp 4 stroke short shaft)

The 3 modifications I've made and why. 6hp carb because it adds a good amount higher rpm on the top end, and better idle. The specific carb I used is from a previous generation model that doesnt have EPA restrictions on it making for better start up and idle. Added hydrofoil to keep the rear of the boat from digging in and porposing. Issue got worse when I added the stabilizers, the hydrofoil fixed that problem. Added a river runner prop saver to protect the prop because I ran the outboard into a tree that had fallen, was submerged and I didn't see it and I hit it pretty good with the prop. Was lucky I didn't break the shear key so this will help prevent damage to the motor and prop from now on.
Outboard (Best deal on line I could find, free shipping, no tax, couple hundred below MSRP)
onlineoutboard...
Tohats 4 stroke 6hp carb ($18 off MSRP)
search.defende...
6hp carb
Davis Doel-Fin Outboard/Outdrive Stabilizer - Black (best for the $$$ super easy installation took me 10 minutes to do) www.amazon.com...
River runner prop saver
www.overtons.c...

[@mikesanchezgsxr]

Don't forget to like and subscribe!

[@djverloo]

This is my experience for upgrading this engine: ( 1999 - 2020 4-stroke mecury mariner tohatsu honda ) Old carburator of mine 5hp has a diameter of 19mm and main jet 68. The new 6hp carburator 21mm and main jet 70. I think the 4hp has the same carburator as the 5hp but with the 62 jet. The 4hp also got a propeller with a differentieel kind of pitch 7.8x7. The 5 and 6hp is standard with 7.8x8 pitch So to opgrade from a 4 to a 6hp you need a new propellor and carburator.

[@orlandomah1186]

Thanks for the tip. Plan on purchasing one, too. And then i will do the carb upgrade as well

[@Philhughes007tube]

My man! I’ve searched the internet everywhere to see if the carb change is the only thing to do to get 6hp power. Thanks

[@nuhhi1]

Camshaft is also different in 6hp motor

[@dmgolub1]

Need a link for a doel fin that can bolt to the same motor. I got a Stingray that doesn't fit. I can't bolt the Stingray on.

[@ambidextria9084]

The hydrofoil was installed slanted versus perpendicular to the cavitation plate. Has this affected the performance in any way?

[@Trapperjohnny13]

Where did you get and model number for hydrfol

[@TheGdspruill]

Nice little setup man I have a 3.5 hangkia with a hydrofoil that I fabricated myself and I'm getting a lot of good top-end out of my 12 and a half foot kayak

[@thijsbuizert8433]

Is it also possible to upgrade from a 4hp to a 6hp when the motor is 2stroke

[@jeremiah9932]

Hey man thanks for the video. Have you noticed a difference with the 6hp. Carburetor? Thinking of doing the same to mine

[@ronprince1478]

Thanks, liked subscribed

[@davidzoltan5263]

Hi, I'm planning installing a 6hp tohatsu carb in my Yamaha 5hp outboard (Parsun) I analysed all two and I'm pretty sure I can make it compatible. I'm asking myself what I risk mechanically if I do that. Do you have an idea? Thank you if you can answer me 🙂

[@gariG2]

Great, thanks Michael. All info in your comments section is very helpful. I’ve heard say you have to change props to match the new power, maybe the 6hp prop. I look forward to seeing it on the water👍🇬🇧

[@chrisrushton3719]

Does the whale Fain make any difference on the 6Hp

[@ДАЙВИНГОХОТАРЫБАЛКА]

Отличный мотор,у меня тоже Тохатсу,только четырехтактный и двадцати сильный

[@jimquantic]

Thanks Mike, One question for anyone interested. I keep reading that the 4, 5 and 6 are "the same" accept for the power, so why do they MAKE a 4hp? What is the upside of having less power than a 6, if the weight is the same? Mileage? Can't be much different?

[@JRkota318]

For my instance in South Carolina if you have a outboard engine 5hp or greater you must register the outboard along with the boat to be on public waterways. So I plan to buy a 4hp and upgrade it to the 6hp.

[@davidalan8704]

Hey Mike, I don’t see the links for the parts you used on this mod.

[@rbeckwith]

Did you have to move the anode to attach the Dole-Fin?

[@begraa]

looks exactly like mine Mecury 6hp

[@buijs1967]

Will the oil not run out of the engine if you transport it on its side?

[@blaircox1589]

Just be careful, I'm not sure what model of canoe you have, but being a canoe, they are rated mostly up to only a 4hp. And because a canoe is not like a true boat designed for planning, the faster you go, the less weight it can carry. You can sink it just going faster.

[@mikesanchezgsxr]

I have outriggers on the canoe that create drag in the water, putting the 6hp carb actually only brought the boat up to about 8mph gps confirmed with the hydrofoil and outriggers on the boat because of the drag. It's not a problem at all for that boat doing the 6hp carb and if you have other components causing drag to slow it down. I might also do the prop upgrade in the spring when it warms up to get it up to about 10mph top speed which is what the 4hp does with no weight, and no outriggers

[@forrestking]

Experts abound!

[@64maxpower]

Are you aware of any thing I can do to tweak my 6hp motor to get more power that you know of? In my boat no matter if I drop it to the last pin the front of my boat climbs too high. Will those fins help if I position them correctly? I like the prop saver you instslled

[@robantonelli5331]

Only the carb is different on a 4 and 6 Hp Tohatsu ? Thinking about getting one , just wondering thanks .

[@blakenitta8849]

can u tell us what fin u put on ?

[@brentcolquhoun9025]

Anyone know where to get that prop guard? Looks like it'll have very little drag compared to the conventional all round ones

[@harryesteves387]

What boat do you run those fins on mate?

[@chuckpatch1230]

where do you get parts from for tohatsu motors ?

[@BloodSweatnBass]

right on thanks for sharing looks like some clean mods

[@tylerw1418]

The carb upgrade is sweet. Never heard of that.

[@ArnaudDeSmedt]

Maybe the ingition of 4hp has 4500 rev limitation and the 6hp ignition gets to 5500rev,

[@mikesanchezgsxr]

Its 5k for 4hp and 5500 for the 6hp. Unless you swap the prop you need to keep that top rpm at 5k or you're over revving the prop for it's pitch.

[@craigirvine7086]

Was thinking about doing the same mod upgrading my 4hp to 6hp but also getting the 8 pitch propeller and adding the hydrofoil fin.My boat will currently plane with me doing around 15knots top speed .do you think the 6hp and hydrofoil will be enough for the boat to plane with two people .its 2.7m air deck with inflatable keel

[@davidzoltan5263]

Brother I have the same configuration than you. (270 cm sib with 5hp) did you increase your speed with your upgrades? Hydrofoil and carb? Eventually prop upgrade? Thanks in advance.

[@craigirvine7086]

@@davidzoltan5263 didnt increase speed but it enabled the boat to plane with two adults in it where as before it would only plane with one adult. Does around 14knots on a cruise . I think with the 8 inche prop it would only plane with one adult but am told would do around 22knots . It had the 6hp carburettor and the standard 7 inche prop on it

[@davidzoltan5263]

@@craigirvine7086 thank you for your informations 👍

[@oimate7673]

Thanks for tips mate 🙌🏻

[@jimcatx3090]

There are 15 hp Tohatsu motors 4 strokes new in the box for 30 dollars on eBay right now

[@tylerw1418]

jimcat X how’s that possible

[@Giggidy69]

You have definitely got that wrong😂

[@strikerone6991]

No need for a larger fuel Pump? Noticed there was an inline fuel filter between the fuel pump and carb did you add that or is that how they come?

[@mikesanchezgsxr]

No. the fuel pump for the 4/5/6 are the same. Yes the inline fuel filter is factory. I have another fuel filter inline by the gas tank as well to make sure nothing gets fouled up in the carb.

[@nopi98]

How fast was it before the modification?

[@mattdellinger2945]

You think the 6hp jets would fit into the 4hp carburetor?

[@hansanders4661]

that wouldn't really make sense as the 6hp carb has a bigger venturi anyways

[@mattdellinger2945]

Hans Anders okay gotcha, was thinking the only difference in the 4hp and 6hp carbs were just the jets. I’m just trying to maximize power from my 4hp...

[@mikesanchezgsxr]

@@mattdellinger2945 no. The diameter of the choke for the 6hp is about twice as big ompared to the 4hp carb. The air fuel mix will never be right if you just seap out the jets. The motor will run way richnif it even rums if you only swap out the jets. I left a link in the description for the carb I ised and it was the best deal I could fimd on tjat complete carb. It wasn't too expensive, right around $100 for it. Click the link for the discription and you'll find the link.

[@mattdellinger2945]

Michael SANCHEZ Thanks for the advice! I’ll check it out. Just trying to get a little more power out of my little outboard without having to switch to an entirely different motor. Happy new year!

[@JackySpearo]

@@mikesanchezgsxr May I know where you bought 6 hp carb?

[@davecox900]

guys the 4hp and 6 hp are total different, compression ratio diffrent top cam and the valves are diffrent too