Beat up old prop causing over-revving?

chillin014

Petty Officer 3rd Class
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Jan 14, 2009
Messages
91
Re: Beat up old prop causing over-revving?

whoa whoa whoa...how do you figure? Its pretty discouraging. When I bought the prop the guy pressed on the hub at that very moment. He said it needed curing time but that it should be fine by the time I took the boat out which was the next day if I recall correctly. He said not to try any fast take-offs, which I did not. What should I do?
 

kartman

Petty Officer 2nd Class
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Apr 28, 2009
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108
Re: Beat up old prop causing over-revving?

hwsiii is talking about the prop slipping in the water, not the hub slipping in the prop.
 

chillin014

Petty Officer 3rd Class
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Jan 14, 2009
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Re: Beat up old prop causing over-revving?

hmmm. i've never heard of this. What causes it?
 

hwsiii

Commander
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Jan 25, 2009
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Re: Beat up old prop causing over-revving?

The wrong prop or too much load in the boat.

H
 

chillin014

Petty Officer 3rd Class
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Jan 14, 2009
Messages
91
Re: Beat up old prop causing over-revving?

The wrong prop or too much load in the boat.

H

Are yall sure I dont just have a crappy weak motor? I'll do a compression test on it soon since I have a tester now.

I only have two people in the boat (myself included) and maybe a 30 pound cooler...so I know its not overloaded. What prop could I possibly get now? I know there are factors I'm not considering but the pitch seems dead on considering the RPM its supposed to be at at wide open throttle.
 

hwsiii

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Re: Beat up old prop causing over-revving?

Chillin, exactly what year and model is the boat, I may have the weight wrong.

H
 

chillin014

Petty Officer 3rd Class
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Jan 14, 2009
Messages
91
Re: Beat up old prop causing over-revving?

Chillin, exactly what year and model is the boat, I may have the weight wrong.

H

It is a 1990 Bayliner Capri. It is pretty small...16 feet 7 inches I believe. I am not sure on the weight either though.
I dont know why...I just can't get into enjoying the boat too much. I'm depending on the right prop to make the boat perform how it should I guess...but the motor is probably weak, it handles like crap, my friend weighs like 50 pounds more than me so the boat is constantly tipped to one side when we are cruising :mad: God forbid we bring any more friends and the thing is struggling to go 10 mph.
 

hwsiii

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Re: Beat up old prop causing over-revving?

Chillin, order a Michigan Wheel part number 072131. It should be the exact prop you had before, but check with Michigan Wheel by giving them your part number from the old prop. That is the one that was on it, so I believe that is a good one to use.

H
 

chillin014

Petty Officer 3rd Class
Joined
Jan 14, 2009
Messages
91
Re: Beat up old prop causing over-revving?

Alright...so I finally got around to dealing with this. I went back to the shop I bought the new prop from and apparently the one I bought IS basically a stock replacement, just bronze material. I left it there for him to "cup" the blades which is apparently just trimming some material off the prop so that it will move more water. He said that is all I can do at this point since the RPM's are at the right speed. Am I expecting too much out of this boat?

I am going to do a compression test on this motor.
 

hwsiii

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Re: Beat up old prop causing over-revving?

Chillin, cupping is different from what you said, it will lose you some RPM, but it should make your prop slip much lower which should raise your speed up if it is done right.


H
 

chillin014

Petty Officer 3rd Class
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Jan 14, 2009
Messages
91
Re: Beat up old prop causing over-revving?

Chillin, cupping is different from what you said, it will lose you some RPM, but it should make your prop slip much lower which should raise your speed up if it is done right.


H

Thanks for the confirmation. That is exactly how the guy explained it, that it would lower the rpm and possibly bring the speed up. It sounds like I have the right pitch though, right? Its not like its a matter of getting a different sized prop?
 

hwsiii

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Re: Beat up old prop causing over-revving?

Chillin, something sounds wrong, let me get bak with you.


H
 

chillin014

Petty Officer 3rd Class
Joined
Jan 14, 2009
Messages
91
Re: Beat up old prop causing over-revving?

alright, no biggie. Just don't forget that the motor is old and may just be worn. I need to confirm this for myself.
 

hwsiii

Commander
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Jan 25, 2009
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Re: Beat up old prop causing over-revving?

In my opinion the motor is not worn out from the RPM you are turning. The cupping ought to reduce your prop slip a lot and thus increase your speed.


H
 

chillin014

Petty Officer 3rd Class
Joined
Jan 14, 2009
Messages
91
Re: Beat up old prop causing over-revving?

hmm well. I just got my prop back from being cupped, I can see where they curved the blade a little bit. THe receipt says the prop is a Michigan "10.5x11" just fyi for reference.
 

ramster

Petty Officer 2nd Class
Joined
Jun 19, 2005
Messages
150
Re: Beat up old prop causing over-revving?

Take your boat to a scrap yard and ask to weigh it, could be your foam is saturated, those Bayliners don't have the best sealing around the floor foam, and if they are not kept covered they get wet. If the weight checks out, I would get Smart Tabs, they totally transform Bayliners. If the boat is in decent shape and you like it, go for the max HP that boat can handle like a 90 or maybe a 115, then she will really fly. 50 hp is just not enough motor for that boat even if it is a good one.
 

chillin014

Petty Officer 3rd Class
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Jan 14, 2009
Messages
91
Re: Beat up old prop causing over-revving?

ah I forgot about the possibility of the foam weighing it down. I will try to get the boat weighed at the Love's gas station out here, they have a weigh station.
 

ramster

Petty Officer 2nd Class
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Jun 19, 2005
Messages
150
Re: Beat up old prop causing over-revving?

You must also remember, when it comes to boats and HP, If a little is good, more is better, never leave well enough alone.
 

chillin014

Petty Officer 3rd Class
Joined
Jan 14, 2009
Messages
91
Re: Beat up old prop causing over-revving?

Trust me, my hunger for more power is bad enough as it is. This boat is old and living its last moments with me however. I will upgrade to something better in the future.

At the moment I'd just like to be able to tow someone on a tube. I hear stories of this boat pulling water-skiiers and it just doesnt even seem possible as-is.
 
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