Difference in Merc 9.9s ?

[KayakJimW]

Hey folks, hope y'all are doing well.  I'm about to pull the trigger on a new 1754 jon boat w/ a 9.9 tiller.  This is something that I've been kicking tires on for a while now, looking for used with no luck, so I'm ordering one.  I know that I want a tiller with electric start and tilt / trim, 20" shaft but I have a few questions about the different models and I'm having a hard time finding certain info...

 

I see there's a 9.9 and a 9.9 pro kicker.  My understanding is that the Pro kicker is geared a little different to troll more steadily at lower speeds, but built tougher / more heavy duty?  Also there is a difference in 3 or 4 blade props that I'm hearing differing opinions on.  My goal is to have a faster top speed (I realize faster is subjective when talking 9.9s but...) if I can get to the back of my reservoirs quicker, that's what I'm looking for.  I'm also thinking carburetor motors may be a little quicker than efi, but efi come with less maintenance down the road?  Am I way out in left field here?  

 

I'd like to hear some thoughts on which 9.9 would be the better choice, and why please.  And maybe what to avoid? For this size motor, I'm not too worried about price differences if I can get a top performer in its class

 

Thanks all!

[Team9nine]

I’m on my second 9.9 engine. My suggestions, based on ‘speed’ being important to you are;

 

Check to make sure your jon boat has a 20 inch transom and not a 15 inch. Match the engine length to the actual transom measurement (short shaft vs long shaft).

 

Forget the Pro Model Kicker and get the standard 9.9 engine.  In hind sight, if you aren't held to a lake restriction, the 15 hp would be a better option/engine.

 

Stay with a 3 blade prop. You’re probably fine with stock pitch, but I’m pushing a deep V and found that exchanging to the smallest pitch prop they make got my rpm’s up where they needed to be, and increased top speed.

Edited September 14, 2022 by Team9nine

[KayakJimW]

Thank you, I value your input.  Yep, it's a 20" transom (21 actually) and my favorite spots have the 10HP restrictions.  Standard 9.9 it shall be

 

Thanks

[Dwight Hottle]

My understanding regarding the difference between the two is the 9.9 Pro Kicker is geared to deliver more thrust & it's more heavy duty than the standard 9.9. They were developed as supplemental motors for trolling on boats that had a primary engine for running at high speed. 

[GRiver]

I think Dwight Hottle is right, the pro kicker is made for pushing a heavier boat at trolling speeds rather top end speeds. 
I’ve had a few tin boats and I’m running a 15 ft mod-v now.

Since you restricted to 9.9 hp, I’ve found weight and load management helped me the most. I do play with prop pitch too. 
Try loading the boat batteries, fuel, gear, etc… so it rides level and still gets on a plane easy. I loaded it to the heaviest I thought I’d ever have it then, moved it around until I was happy with it. The tin boats can be weight sensitive.  Then I got a tach and started playing with the prop, I don’t know how much you want to get into it.

[WRB]

You can convert 9.9 Merc to 15 hp by changing the carburetor and cylinder shim plates, same engine.

Tom

[KayakJimW]

Thanks all.  The 9.9 HP upgrades are pretty neat for sure.  I'm looking at EFI instead of a carb and there's even a way to boost those.  There's a little metal restrictor that can be removed and looks pretty simple to do, but here's the kicker (pun intended).  I've seen my buddy get stopped by game wardens because they thought he was going too fast for a 9.9.  He has a Johnson 9.9 on a very light boat, and they made him remove the cover so they could verify serial numbers and check for enhancements that would've taken him over the 10HP limit.  He was good, but that alone makes me shy away from doing it.  I've also wondered if some of these mods (Suzuki's, Hondas, etc can all be pretty easily tweeked) makes them run above their recommended RPMs and could potentially do some damage over time? 

Eventually, I'll hook up a tach and play with different props to squeeze what I can out of it that way, but for now I'm just happy to get this thing ordered. 

Great recommendation on weight distribution too, sounds like that could affect some MPH for sure

[Maggiesmaster]

Mercury small motors are made by Tohatsu. They’re reliable motors, but a 9.9 on a 1754 won’t set any speed records! I wasn’t aware you can convert them to 15 horsepowers.

[MickD]

If you have a choice between carb and EFI, take the EFI.  I can't imagine both being offerred, but I won't buy a carb engine any more.  EFI's start and run better, last longer without maintenance.