2018 20hp efi tohatsu

boater1234

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Does Anyone Know if The New 2018 20hp Efi Tohatsu Has the Same Prop Shaft As in the 14 spline shaft because I just ordered a new 11 pitch prop and it says fits 2007 and newer but I just wanted to make sure,thanks for any info .
 

Sea Rider

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Check Tohatsu Prop Chart on their web page, should have one...

Happy Boating
 

jbcurt00

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Avoid asking the same questions in multiple places.

It is a long holiday weekend, so some replies may take longer......

Might have considered using the prop forum instead of the non-repair OB discussuons. If you want it moved, just ask any Mod to move it, dont start a 3rd

Oh, and in the original topic, you didnt specify which hp you have on order
 

boater1234

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I'm hoping tohatsu guru could tell me because I can't find it anywhere.
 

boater1234

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Well I love this engine but I'm having issue with it starting right away as an efi should do like my suzuki did. Most of the time it takes 4 or more pulls to start this engine and it shouldn't imo. My suzuki started every time in one to 2 pulls so I don't know what the issue is with that.


2nd thing is I went with the 10 pitch prop, it over revved, so I went with a 11 pitch prop, again at wot it over revved to my suprise. The boat had a total of over 1000 lbs of weight so I figured an 11 pitch prop would do it but it just,I mean barely touches the rev limiter, once I back off just a hair the red light goes off and the missing sound goes away immediately. I realize this motor has tremendous power but should it need a 11.5 to 12 pitch prop? That seems to big but I've tried different trim angles and stuff and it still over revvs which is crazy. So I'm either getting a 11.5 or 12 pitch prop soon.

3rd thing I noticed and I'm guessing it' desiged like this but the motor mounts on this motor seems way less stiff then near any 20hp I've ever run. The powerhead has more play then traditional 20hp 4 strokes, is this by design and why is it like that,I'm curious for what the reasoning is???? It runs with tremendous power for a 20hp, it's way more powerful then an 20hp 4 stroke I've run yet and it'​s a 333 CC engine which is less then most of the other 20hp like yamaha at 362 and original tohatsu /merc at 351,so I'm trying to figure out how this engine runs faster then my 20hp suzuki and has a ton more power that I need a larger prop? Not that I'm complaining, I'm just suprised.

Thanks for any info
 

Sea Rider

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This is a tiller steering OB, right ? Before playing with prop pitches wildly you should invest time in water experimentation to get the max out of that combo, which by the way is ?

With deck weight evenly distributed trim OB for combo to run parallel to water level at plane, when that happens will have AV plate and prop shaft riding parallel too. That's where the prop achieves the best thrust as all blades bites even at same angle of attack.

A must check at which lower leg is water flow passing at speed. Tohatsu lower legs loves for water flow to skim right under small upper water deflector plate. If in need to rise, chop transom down it's other story, at least need to determine so. If at wot OB sits to high prop will spin with less water bed, will achieve slight more wot rpm with less prop thrust.

Have not stated when OB over revved how loaded combo was, did the rev limiter ever kicked in or not ? sometimes you need just a half pitch to be at the max wot range as loaded and rev limiter staying home. Can send that 11 to a prop shop and have it repitched to a 11.5.

Having 10 and 11 props should make a wot test say solo boating and as currently loaded and report max achieved rpm with both props to check wot rpm gain or loss difference between both pitches, .

Bottomline, it's near impossible to dial best prop performer for your application on first try, usully on second if not on third. Took me testing 3 / 9, 8.5 and 9 pitch props to dial best prop performer as fixed loaded. The 8.5 did the final trick having already a previous OB height optimization.. OB's powering light applications could over rev depending on the pitch size factory delivered.

Happy Boating
 
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boater1234

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I stated it has over 1000 lbs of total weight in the boat,that's boat, engine,people ,gear and gas,plus a light pvc floor. It's trimmed correct. It's a tiller model and the anti cavitation plate sits near level with the bottom of the boat. Nothing is wrong except it over revvs just a hair when I push it to full wot. I back off I mean just a hair and it goes back under the max rpms so I'm thinking I need a 12 pitch and that's what I think I'm going to do. I know its not over heating or if it's the oil pressure warning,it's 100% to small of a prop so I will get more than likely the 11.5 or 12 pitch and that should take care of the problem I'm sure.
 

boater1234

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It will cost me probably near $40 or more to add a hslf pitch when I can just buy a brand new prop for $60. The 12 pitch is a hair bit more. I' probably going 12 pitch.
 

Sea Rider

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Over revving slightly is not an issue as currently loaded. Just watch tach and throttle back when lightly or medium loaded. Nobody runs full grip all the time unless working for an Oill Company or when fuel budget is not an issue.

Made a prop investigation, there's no 12 pitch prop, but there's a 11.5. From experience, Tohatsu OEM props or equivalent ones can achieve easily + 500 wot revs going 1full size pitch, so 1/2 pitch should drop half of that. Only checkable on a wot run..

Happy Boating
 
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boater1234

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12 pitch prop on the way to my house by tom,they make a 12 pitch prop for it,solas. Here is the number 5111 093 12. 14 spline and fits my motor perfect so I'm going with that and that should take care of the problem and maybe even help me pick up a mph or 2. I will let you know what type of performance it gives me as well as it staying under the Rev limiter. I have a tach also and I'm going to install it this week with the 12 pitch prop.
 

boater1234

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I know what your saying though as my manual says the same thing,the biggest they make is a 11.5 pitch but it's' false.
 

boater1234

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Over revving slightly is not an issue as currently loaded. Just watch tach and throttle back when lightly or medium loaded. Nobody runs full grip all the time unless working for an Oill Company or when fuel budget is not an issue.

Made a prop investigation, there's no 12 pitch prop, but there's a 11.5. From experience, Tohatsu OEM props or equivalent ones can achieve easily + 500 wot revs going 1full size pitch, so 1/2 pitch should drop half of that. Only checkable on a wot run..

Happy Boating

Are you saying that 1 pitch up or down can make a 500 rpm difference?

I'v never heard that before, rule of thumb by every website I've ever been on or from every person I've ever talked to said one pitch up or down moves the rpms up 200 or down 200,I've never heard of a 1/2 pitch moving rpms 250 down or up. But I guess anything is possible.
 

boater1234

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I also go wot around 90% of the time, I only go slow in no wake zones,any other times I'm flying,lol.
 

Sea Rider

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On ligh, medium light inflatable applications that's possible, the last 4 prop maximizations done playing with one full pitch up or down gave those readings with top air inflated inflatable.. This rule of thumb must not always be consider as only applies on large and heavy boats. Why do you think than on larger OB's you can only find +,- 2 full pitches props.

The issue about rule of thumb that you have read it somewhere, at boating forums, marina's boaters talk is that none of them considers application and weight, all boats are thrown in same sack which is absurd. In some cases a 0.5, 1 inch repitch at a prop shop is the way to go if 1 or 2 full pitches aren't doing their homework right.

Happy Boating
 
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TOHATSU GURU

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It should start on the first pull so something is wrong. Propeller pitching is best done by trial and error and a 12 pitch for a 20 seems high, but with the Tohatsu's power output it's not abnormal. I don't know what you mean by play.
 

boater1234

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I noticed the tohatsu powerhead or whole top end as a whole has a totally different motor mounts design. Like my suzuki's top end was really stiff,the tohatsus is much different, there seems like I said the whole top end of the motor just shakes a bit more due to not being as stiff but I also noticed so much less vibration in the tiller.

what I mean is if you push the whole cowling the whole powerhead including the cowling is easily moved around by hand,with all other outboards the whole top end is extremely stiff so you need to push with pressure on the top end of the outboard to get it to move at all. The tohatsu has what I explain a much loser or softer powerhead as a whole ,seems by design.
 

boater1234

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Well after all this I have decided to sell the tohatsu and the upgraded tiller on the merc. I love that new tiller handle, it' imo state of the art and the comfort and features it possesses is incredible. Again had I known the merc was coming out I would have waited to get it instead of the tohatsu just to have that comfort in a tiller. Maybe to some or even most it may not be worth an extra say $300 to upgrade to a tiller like that but for me if I'm going to fish 3-5days a wek I need all the comfort I can get and I just love how it starts out as a center tiller for both hand operation,just genius who finally thought of the guy driving the tiller and knowing how much abuse and pain when driving a tiller. Sometimes my arm goes numb driving or the vibration tears my arm up,this type of tiller addresses that problem.


The tohatsu powerhead is on the merc so I get identical performance and lose nothing in that aspect. Can't wait to get this engine in mid march.
 

boater1234

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Tohatsu guru,do you in your serious personal opinion think the merc with the new state of the art tiller handle is worth the upgrade???? I'm curious on your opinion on this. All in all it would cost me like $300-$400 for the merc once I sell the tohatsu. I love the look and feature of the new merc tiller handle, especially for comfort.

I know the merc is just a glorified tohatsu that costs a bit extra money but I really love that tiller. I absolutely love the way the tohatsu engine runs, it is by far the best, quietest and most powerful running 20hp 4 stroke outboard I've ever run. So I know the merc will run the same since it's the same outboard but different paint and tiller handle.

Basically I'm wondering if this tiller handle is all kicked up as what they are advertising or is it just way over hyped? I' m going into this as a very long term investment so I'm feeling it' s worth the upgrade but I also value your opinion very highly so it means alot to hear your thoughts on what I'm thinking. Thanks for any info.
 
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