Confused on props

Hogwash · January 06, 2023, 07:41:47 PM

1999 ranger Cherokee 17' V hull
With 90 Johnson. Prop that came on boat is aluminum 14x19

I have zero issue getting out of the hole but only get 37 fully loaded. What prop would give me a little more top end?
I also have prop torque pretty bad under power and I understand (maybe incorrectly) that a different or SS prop may would help

Chuck

BassmanRudy · January 06, 2023, 08:59:13 PM

I've heard changing to a stainless steel prop of same dimensions will help. Mainly due to the thickness of the blades. See if a local prop shop will let you try one with say an "intent to buy" if you like the results.

Higher pitch will give you more top speed.

What's your RPM range? My 90hp mercury had a 54-5800 fully trimmed out range but seemed to like 5650 the best. And honestly I never broke 37mph after adding Talons and the extra battery.

Can also try moving heavier stuff to the back and make sure it's "even". I kept heavier stuff on the starboard side to offset my weight as I was solo most times.

Princeton_Man · January 07, 2023, 06:26:10 AM

Finding the perfect prop can be frustrating. Stainless steel props don't flex under load, so a 14 pitch will stay 14 pitch as you're hitting the throttle to come out the hole. Stainless props are heavier, so it will take a little more power to spin up. Numbers will help a lot. If you know what the wide open throttle RPM are, that will help determine the desired pitch for top speed, but going up in pitch will have a negative effect on your hole shot.

Do you know what are others with a Ranger Cherokee 17' V hull similarly powered getting? It seems to me Capt Steve had a similar vessel. I'll send him a PM and ask him to chime in.

Princeton_Man · January 07, 2023, 06:41:47 AM

As for the torque, you might have a torque trim tab over your prop, if not you can add one. Setting it the extreme right will correct the torque at the wheel.

Hogwash · January 07, 2023, 08:05:13 PM

Quote from: Princeton_Man on January 07, 2023, 06:41:47 AM
As for the torque, you might have a torque trim tab over your prop, if not you can add one. Setting it the extreme right will correct the torque at the wheel.

It's not pulling on steering wheel. The boat just runs leaning left pretty hard till you get it fully trimmed and then it's slightly better.

I just got my tach fixed and will have to report back on rpm's
Another thing when I use any of the prop finders online they usually show I should be running more like a 13.5 x 17.

D.W. Verts · January 07, 2023, 11:47:53 PM

That's a lot of diameter...

Does the boat porpoise at low speeds?

Dale

FD · January 08, 2023, 03:34:08 AM

A lean to the left is probably not torque. More likely it's a balance issue.

Do you have single or dual gas tanks and where are they located in the boat?

Sent from the very edge of civilization...where I belong

big g · January 09, 2023, 01:28:57 PM

A long time ago I had a Suzuki 115 with an aluminum prop. I got my best top end with that prop because I think it flex a little at top speed. Better than the SS replacement, same pitch. Anyone experience this?

Hogwash · January 09, 2023, 02:53:20 PM

Quote from: FD on January 08, 2023, 03:34:08 AM
A lean to the left is probably not torque. More likely it's a balance issue.

There is nothing out of balance on loading boat. It has built in gas tank that seems to be about mid boat. No idea if it is centered

Do you have single or dual gas tanks and where are they located in the boat?

Sent from the very edge of civilization...where I belong

Princeton_Man · January 09, 2023, 04:21:04 PM

Quote from: big g on January 09, 2023, 01:28:57 PM
A long time again I had a Suzuki 115 with an aluminum prop. I got my best top end with that prop because I think it flex a little at top speed. Anyone experience this?

I've always thought the prop flexed during take-off, reducing it's pitch, then once on plane the prop returns to it's normal pitch which would account for the better speed. Aluminum and alloy props are much lighter and spin up a lot faster on smaller motors.

topdsm0138 · January 09, 2023, 07:53:58 PM

I never gave my Suzuki DF25A that much thought on another prop choice. Here's the weird part. If I only have 2 people in the boat, it has a great top end. It I go to 3 people, I have less top end speed. (Now for the weird part) It doesn't matter how many or less people I have in the boat, it's low end acceleration remains the same. And I've always read that props can help or hurt one or the other (Speed/Takeoff). It's like the motor was made as and meant to be a low end power workhorse over a speedster.

Sent from undisclosed location. -Tiller Mafia

Princeton_Man · January 10, 2023, 05:53:05 AM

I heard back from CaptSteve. His Cherokee was a F&S model, had a 150 four stroke, and topped out around 50mph. Everything considered, your top end might not be that bad.

caddyjoe77 · January 23, 2023, 08:58:47 PM

In my opinion, i think you are doing pretty good for a old school ranger with a 90 doing 37/38.

i had a triton 17 with a 115 and I think it did 47. You might be able to touch 40 but it might cost you more than its worth.

Princeton_Man · January 24, 2023, 10:07:53 AM

Quote from: caddyjoe77 on January 23, 2023, 08:58:47 PM
In my opinion, i think you are doing pretty good for a old school ranger with a 90 doing 37/38.

i had a triton 17 with a 115 and I think it did 47. You might be able to touch 40 but it might cost you more than its worth.

I agree.

Hogwash · February 03, 2023, 08:28:03 PM

Finally got out today after getting tach working. It shows I'm doing 4600 rpm wot

BassmanRudy · February 03, 2023, 09:56:36 PM

4600 seems to be just at the low end of the range-- 4500-5500 based on this chart.

Do you have adjustable trim to see what it does as you adjust it? Not really sure otherwise but the speed seems good to me.

BassmanRudy · February 03, 2023, 09:57:31 PM

Here's the chart I found.

Hogwash · February 04, 2023, 06:28:07 AM

The 4600 is trimmed up wot. Is this acceptable rpm being in the lower range or would I benefit by going to a 17 pitch from the 19?

BassmanRudy · February 11, 2023, 03:07:26 PM

Can't believe I forgot to mention these guys at first...

Company called PowerTech out of shreveport, Louisiana has really helped myself and other bass club members out with numerous prop rigging questions/issues. I'd def give them a call and see what they recommend. Great customer service!

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