Crestliner 1750 Bass Hawk – Prop recommendations

I am looking for some advice on prop recommendations for my 2018 Crestliner 1750 Bass Hawk with a 115 Mercury Pro XS. I am having serious issues with hole shot and then porpoising. With the boat loaded down, 2 teenagers and myself, getting on plane is a struggle and then once on plane, I can barely touch the trim and we start to porpoise. This starts to happen around 5100-5300 RPM right when the engine starts to sound good like it is not struggle any longer.

My merc has 2.07:1 gear ratio with a 12.7” 19P four blade Spitfire stainless steel prop. Thoughts, suggestions, or questions for more info to provide some ideas?

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Unless that boat is a lot lighter than most 17.5 footers, I’d say your over propped. I had a 1750 Fishhawk with a 17 pitch spitfire that worked quite well.

What is your WOT RPM trimmed up? That will tell if you have the right size and pitch prop?

The stainless spitfire is what’s in his pics, but it’s too big. I believe Crestliner recommended an aluminum 17 spitfire originally. That said you maybe could have ran a 17 stainless Spitfire or would’ve had to go to a 15.

Not getting trim is a bit more a of a concern. This could be prop related or there’s something else wrong like engine height, hook in the boat bottom, possibly weight distribution is way off, or even transducers hanging too low below bottom.

bigcrappie wrote:

Switch to the 4 blade Spitfire X7 prop

This would be my suggestion too. 4 blade props tend to get the boat on plane a lot quicker and that sounds like a major problem right now.

He has the 4 blade stainless spitfire already. I would try the same prop in a 17 or 15 pitch and possibly lower your motor a hole if you can. that should make a lot of difference.

Mr. Pike 81 wrote:

He has the 4 blade stainless spitfire already. I would try the same prop in a 17 or 15 pitch and possibly lower your motor a hole if you can. that should make a lot of difference.

My bad. I thought he had a 3 blade version.

Prior to trying a 3 blade 13.25x17p prop yesterday, I was in the 5,100-5,300 RPM on plane WOT and trimmed up. Now I am up to 6,000-6,100 WOT.

How is the hole shot and porpoising?

Hole shot was okay, but not great. Can tell the 3 blade has more slippage over the ( blade.

As for the porpoising, it was a bit better. Seemed like the higher top end speed and higher RPMs helped keep bow down a little more.

I had installed smart tabs previously, but have them off right now. I am going to put them back on with this 3 blade prop and see how that might help both the hole shot and porpoising.

First step, speaking from experience, make sure you have a very accurate reading of what RPM’s you’re running and know what your engine is supposed to run at WOT. The standard tachs cannot be trusted. I highly recommend Vessel View gauges or mobile app if you don’t have them.

Have you played with engine height? With a stainless prop you can run it much higher, which in my experience should help with porpoising. Raising the engine reduces drag. I’ll preface all of this by saying I have zero experience with your type of boat and my experience is a little apples to oranges. But, I went through a similar process on my Alumacraft 185. I’m running a Tempest 19p 3 blade and it works very well for me except when running a pretty heavy load. I’ve raised my motor 3 holes from bottom and can go to full trim up at WOT with no porpoising and minimal blowout on sharp turns. Besides going to a stainless prop, raising my engine provided the biggest improvement to performance. Another thing to play around with for hole shot is the PVS plugs in your prop. After verifying RPM and proper engine height, then spend the time zeroing in on the correct prop.

If the 4 blade still isn’t working, it could be a motor height issue