Prop help please.

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alldodge

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I would suggest use the 19 for a while during normal operations. Might wind up loading the boat more or less and this will also impact overall performance. Your at a good spot in the rpm band
 

d75bender

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Thanks for the input guys, I'll stick with the 19p prop. My normal cruising speed around the lake is about 40-45mph anyway. Thanks again for the recommendations and suggestions.
 

Faztbullet

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The pitch on a Renegade Bass props different than other 4 blade props. This equates into a rpm that is slightly different than other 27 pitch 4 blade props. "Typically" if you run a 3 blade and go to a 4 blade you will go down 1" in pitch for the 4 blade to get similar rpm numbers as the 3 blade...Let's say you are running a 3 Blade 24 Raker and you go to a 4 blade Razor you would want the 4 blade Razor to be 23 pitch. With the Renegade props they are different you go up 1 in pitch. In other words a 25 Renegade is similar to a 23 Razor 4

FYI...most people who run a Renegade need a blow out ring (or sometimes its called a weed ring) to help with blow out on the holeshot. The outer barrel of the Renegade is smaller than 3 blade props. That allows more exhaust venting on take off. If you have too much venting the prop will blow out (aka not hook up) Try it without a blow out ring and if it does okay then no problem. If it vents too much then you will need the ring.
 

QBhoy

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Glad you are getting somewhere but I fear if you run that 19” for too long it won’t end well perhaps.
All the best.
 

jimmbo

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Glad you are getting somewhere but I fear if you run that 19” for too long it won’t end well perhaps.
All the best.

The 19 is running in the upper half of the Range
 

QBhoy

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The 19 is running in the upper half of the Range

Hi jimmbo....if I was to hazard a guess and thinking about what this set up should be like...I’d say that this is hitting the limiter and the tacho is less than accurate ? Every bit of sense in me is saying that this should run a good few inches more pitch. You’re likely thinking the same perhaps.
 

QBhoy

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Especially thinking about the feedback that there was plenty more throttle to go...unless I’ve miss read.
 

d75bender

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I was thinking the same thing QBhoy, I had quite a bit of room left on the throttle before I was WOT. So I returned the 19p prop and got a 23p prop. I honestly traded it in because I knew I wasn't going to be able to not go WOT and I didn't want to risk my engine. The 19p was running in the upper half of the rpm range only because I backed off the throttle but had quit a bit more throttle to go. I know me and I'll run it WOT to often to risk keeping the 19p on there. I'm taking it out this Tuesday and will report back the details.
 

alldodge

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I misunderstood what you were saying with the 19, since your not getting to WOT and still be within range, then you need more pitch as QBhoy mentioned
 

d75bender

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Hey no problem AllDodge, you helped me out a ton. Everyone has. I appreciate everyone's help so thanks to everyone. I'll post the details after Tuesday when I take her out.
 

d75bender

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Ok, Got the 23p installed and took it out today. WOT rpm's were at 5100 with 1 person, about 50lbs of fishin gear and got her up to about 57.5mph on GPS. No slipping what so ever, still smooth as heck like the 19p prop and was really happy all around with the prop and performance. Was hoping to break 60mph but there's only so fast a 150hp will get her. Thanks again for all the help.
 

Chris1956

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You are a bit overpropped, IMO. Check WOT RPM with 2 or 3 people and see what you get.

A 21P prop would put you in the 5500 RPM, plus you might gain a few more RPMs by being more in the power curve.
 

d75bender

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Returned the 23P and finally got my 21P in today and put on the motor. Taking it out next Tuesday (18th) and will report back with all the details.
 

d75bender

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Ok, went out yesterday with 2 people, full gear using the 21p prop. I wasn't to happy with the performance right off the bat but it could just be me needing to readjust how I drive to the new prop. At certain times while driving it felt like it wasn't grabbing the water like it should. I normally drive where its throwing up just a tiny little rooster tail, like just barely throwing up water when I'm at WOT. As the day went on I kept my trim a little lower and it felt good. With 2 of us in the boat I was at 5500rpm's @ 53-54mph. Which is only 3 mph less than when I had the 23p prop. I'm gonna go out next Tuesday by myself so I have a better reference on the prop because normally it's just me by myself. This time I had 2 adults with all our gear. If by myself I'm still noticing it not grabbing like I should I'm gonna get that 23p prop back. They're the same brand, same model of props just different pitches.
 

jimmbo

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deleted, as my question was answered in the previous post
 

WesNewell

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You'll probably overrev with a 21p by yourself. As long as you get 5000rpm with 2 people and gear, I'd say you're good.
 

d75bender

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With a 23p by myself I got to 51-5200 rpm's @ WOT aprox 58mph.
With a 21p with 2 adults and aprox 50lbs of gear I got to 5500 rpm's @ WOT aprox 54mph.

The 21p right from launch just felt "Weird". Hard to explain but it just didn't feel like the other props, it almost felt like I didn't have the prop seated correctly or something. It is seated correctly, I ran it for a few hours that day and felt better as the day went on and I adjusted how I drove it. I verified installation after I pulled the boat out of the water as well. Even with the 19p prop it felt to grab the water better and didn't feel like it slipped at all. The 23p felt smooth like the 19p. The 21p is the only one that felt different but the 1 thing that was different between all 3 is that with the 21p I had 2 people onboard. So I'm gonna take it out this coming Tuesday by myself and see if that's the difference.

But if I'm hitting 5500 rpm with 2 people I think the rpm's could go to high by myself. We'll see...
 

Texasmark

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I believe this is the thrust washer...If it's just stuck on there then I believe the prop would fit. Just didn't know how hard I could pull on it without messing something up.

On Mercs, the prop shaft and washer are wedge shaped for an interference (tight) fit to prevent vibrations and there may be some corrosion involved also.

My approach would be to shoot it with PB Blaster type penetrating oil, and using my rubber mallet and a piece of 1x4 wood putting the wood behind the washer on one side with hand pressure applied pushing against the LU housing and washer, taking the mallet and striking the other side, or tapping lightly with a 10 oz ball-peen hammer, rotating it around till I got it loose.
 

d75bender

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Thanks for the tip, I got it off long ago thus the changing to a 19p then a 23p and now a 21p prop. The problem was the previous owner put a Merc thrust washer on a Rude engine and it was stuck on there pretty good. A couple of small taps on the washer with a hammer broke it lose. Like I said in my previous posts I've had boats before and changed props before but have never had one stuck like that...because I've never had a mismatched brand of washers like that before. Better to ask then to break or force something. Every prop I've changed before that one the washer just slid off.
 

d75bender

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Ok, It's official...took my boat out today with the 21p prop by myself and don't like it. The boat handled and performed better with the 23p. Got basically the same stats as I did with 2 people as I did by myself with the 21p prop though. Got her up to 5500rpm's at 55mph WOT by myself. Still felt like it would slip at times when I'd trim it up a little, it just doesn't feel as smooth as it did with the 23p. With this 21p prop it likes the trim low, just doesn't feel right or at the very least doesn't feel as good as it did with the 23p so I'm probably gonna switch back to the 23p.
 
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