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I recently purchased a Montauk 190 (19’) with a Merc 115 hp 4stroke. I previously owned a Montauk 17 powered with a Yamaha 115hp 4 stroke & it was super powerful.
The 115 Merc just seems really slow; it’ll cruise at 25-28 mph but it takes way too long to get up on plane.
One issue is elevated on; the boat is used almost exclusely on Lake Tahoe , CA, elevation 6224’.
I’m considering repowering with a Yamaha 150 hp 4 stroke but am looking for advice on what brand, hp & prop size would best suit my recreation needs.
Thanks in advance for any info!


(changed to proper name of Montauk 190 for clarification)

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Lake Tahoe does NOT require a 4 stroke motor.
They only require CARB 3 or better for emissions.
The newer 2 strokes that are CARB 3 rated will work on Lake Tahoe.

Your 2011 Montauk 190 has a max hp rating of 150hp
http://www.whalercentral.com/userphot...lbum_id=35

Go for a 150hp if you need the most hp you can get.
2 stroke or 4 stroke
http://www.whalercentral.com/articles...ticle_id=6

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I have a 190 Montauk with the Mercury 150 HP fourstroke.

At 6000' elevation, and the right prop (15 pitch, I think), we get up to 42-43 mph depending on how loaded up we are. Last week, we were up at 8000' elevation, and with two on board, 37 mph was max.

I REALLY like the Merc 150, but for altitude, it seems like a Verado would be ideal, since it's supercharged, and wouldn't lose as much HP at altitude.

That being said, the 150 Mercury is a great motor and I think most think that the HP is somewhere around 165. It's a big displacement engine for it's HP, so the theory is that it should last a long time. Maintenance is super easy, too.

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The Verado is no longer made in 150hp.
https://www.mercurymarine.com/en/us/e...50-400-hp/

See our links for "Current Engine Choices" as shown above for other models.
http://www.whalercentral.com/articles...p?cat_id=4

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Mercury now offers a “Pro XS” variant of the 150 Fourstroke. Supposedly it is tuned to produce additional power over the standard version. It has some additional features over the standard version as well. It is lighter and has more displacement than Yamaha 150 or Evinrude G2 ETEC 150. Definitely worth considering if you need extra grunt at altitude.

But any of these engines is going to serve up gobs more power than what you have.

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We have a 190 Montauk with a 135HP Verado. We operate at sea level. The engine is exceptionally strong for a 135. I would contact a few larger Pacific Coast Mercury dealers to see of a used 135 or 150 HP Verado may be available. A new 115 Mercury could be an acceptable trade in. Of course you would almost certainly have to have the rigging done at the dealership. Do You have a trailer?

The supercharged Verados deliver incredible performance.

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While I would ask why the salesman didn't try to get you to upgrade you to the 150 FourStroke given the performance hit an engine takes at elevation, I will skip this because your salesman is a moron for not already cautioned you the Montauk 190 is marginally underpowered with a 115hp at sea level.

For owners who take their boats up to the various lakes above sea level, a separate prop is necessary to offset the reduced air density.

In this performance report from Boston Whaler, see page 2, http://bostonwhaler.com.s3.amazonaws....ANCE-2.pdf the standard prop is listed as a 14 3/8 x19 Enertia. You will want to reduce pitch.

The exact reduction is dependent on your elevation and how your boat is loaded. I would visit a Mercury dealer in Tahoe and ask to try out a Enertia 14 3/8 x 17. Given 6000, I would start with a 15" pitch Enertia.

Note - If you select a different brand or model of prop the sizing will be completely different and will require extensive trial and error.

Note #2 - Harpoon's Mercury 150 FourStroke uses a different gear ratio and the prop size is different than the Mercury 115 Fourstroke.