Tohatsu 9.8 or spring for the new 9.9 EFI?

[MuskieGuy]

Came across a 2017 tohatsu 9.8 with virtually no use for a somewhat reasonable 1700 bucks. Debating between that and the new 9.9 EFI. Is the EFI with the bigger block worth the extra money? Or is the weight savings and cost savings a bigger factor? Also considering the EFI in hopes someone figures out an easy way to convert it to a 15/20. What are your thoughts?

 

[pvanv]

The 9.8 is substantially lighter, but is carbed. I own one and love it. That said, if the 9.9/15/20E had been available when I bought the 9.8, I would have likely have gone with the EFI. Yes, it is possible to upgrade, but you must change the ECU and a couple other items, so probably not cost effective.

 

[MuskieGuy]

Will the increase in displacement along with the EFI make it a faster motor...hole shot and/or top end? If so I might just go that route anyways.

And I know it's not cost effective, but the closest lake to me is 9.9 restricted. I want more power for the bigger lakes, but I also want to be able to go out after work at my local lake. I'm willing to sacrifice so I don't miss out on local fishing. Would a future upgrade might be cheaper than buying 2 motors? I know with the 9.8 that I'm looking at there isn't an option.

 

[Sea Rider]

A 4 stroke 9.8 is a 209 CC engine. A 9.9 is a 333 one. More CC renders better performance. Prop it right to run middle to max wot rpm range factory stated as usually loaded.

Happy Boating

 

[pvanv]

3rs064010m

ecu assy (20)

$900.00

You would also change out the intake restrictor. Yes, it's cheaper than 2 motors, but not exactly cheap.

 

[MuskieGuy]

Thanks guys. Still not sure whether I should just go cheap or bite the bullet on the new EFI. Decisions decisions.

 

[km1125]

I haven't seen the new EFI motors yet. Are the new 9.9/15/20 similar in weight and size to the old 9.9/15/18 4S or are they smaller and lighter??

 

[pvanv]

95 pounds in short, 121 in ultra long ***.

 

[ahicks]

Thanks guys. Still not sure whether I should just go cheap or bite the bullet on the new EFI. Decisions decisions.

Well, somebody said EFI's are great until they aren't, and generally, I couldn't agree more. With carbs, somebody used to doing a lot of their own work at least has a chance to clean them.

 

[Sea Rider]

If plan being a mechanic guy with 4 strokes EFI ones, plan buying a Lap Top, Tohatsu EFI Software and cable set to check, adjust ECU parameters if wanting engine to kep running spot on along avoiding costly dealers charges doing so.

Happy Boating

 

[ahicks]

Many times, Bombardier being a prime example, the required software is not available, at any price, unless you are a dealer. Maybe all companies aren't like that, maybe they are. I don't know. It's not going to be an issue here!

 

[TOHATSU GURU]

The software can be purchased through any Evinrude, Mercury or Tohatsu dealer.There is no restriction on resale by the manufacturers...At least by Mercury and Tohatsu.

 

[MuskieGuy]

Made the decision to go with the new 9.9 EFI. The option to upgrade to a 20 is a no-brainer. Might have to wait a little while as it is somewhat expensive. But it beats switching out motors.

The restrictor also appears to be very easy to remove...there are a number of videos of eastern Europeans taking them out on youtube.

So quick question... would removing the restrictor alone increase performance? On those vids of the Europeans taking them out, it doesn't appear they're changing the ECU's. Of course, I don't speak their language, so I cannot say for sure. But would it increase performance without any other changes? Maybe not to 20hp, but at all? Just curious since that would be a free upgrade to do immediately.

Also, how difficult is it to change the ECU's? Is it really just a bolt or 2 and the (very) careful disconnection of a few wiring harnesses?

THANKS!

 

[pvanv]

You MUST change the ECU or you will run too lean if you remove the restrictor. The 9.9, 15, and 20 ECUs are all unique, and have specific advance curves, etc. The ECU bracket comes off with 2 bolts. The ECU connects with a single plug.

3RU064010M

ECU ASSY (9.9)

3RT064010M

ECU ASSY (15)

3RS064010M

ECU ASSY (20)

 

[Sea Rider]

Do you think that Tohatsu will manufacture a EFI outboard in which by only removing a simple air restrictor could bump it to next HP one. NOPE that won't happen as more HP is associated with a higher price you will need to pay if wanting going that route.

Those amateur EFI conversion vids seen on YouTube are up to nothing. Only works if you happen to know the software parameters you can modify with a Lap Top on HP models sharing same CC while happens to share same excat ECU model.

If not, to each HP it's own proprietary costly ECU..

Happy Boating