5 seconds @ 5000Rpm safe for 3.0L ?

2fast4u_evinrude

Petty Officer 2nd Class
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Jul 19, 2010
Messages
155
I know its not recomended to run a 3.0L mercruser engine at 5000Rpm but I just recently purchased this boat and its equiped with a quick silver Power 2 varible pitch prop. The pitch wont shift until I rev till at least 5000 rpm for about 5 seconds.
 

Bondo

Moderator
Staff member
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Apr 17, 2002
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71,082
Re: 5 seconds @ 5000Rpm safe for 3.0L ?

Ayuh,... Then Fix the Prop....

It's a roll of the dice at every launch the way it is....
 

Rocky_Road

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Oct 8, 2008
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1,798
Re: 5 seconds @ 5000Rpm safe for 3.0L ?

I know its not recomended to run a 3.0L mercruser engine at 5000Rpm but I just recently purchased this boat and its equiped with a quick silver Power 2 varible pitch prop. The pitch wont shift until I rev till at least 5000 rpm for about 5 seconds.

You are assuming that your tach is 100% accurate? I know that I can 'tap' the face of mine, and it may deviate one way or the other....

You may want to hook up a reference shop tach, and see just where you actually are.

Happy boating!
 

steelespike

Supreme Mariner
Joined
Apr 26, 2002
Messages
19,069
Re: 5 seconds @ 5000Rpm safe for 3.0L ?

Probably a good idea to varify the tach.
Have you tried running at about 4800 see if it will shift?
Also perhaps a quick reduction of throttle for half second or so might kick it over.
 

2fast4u_evinrude

Petty Officer 2nd Class
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Jul 19, 2010
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155
Re: 5 seconds @ 5000Rpm safe for 3.0L ?

I tried running it at 4600 rpm and it wont shift. It has to be at WOT before it will shift. I see that there is some adjustment screws on the prop. Maybe I have to play around with it?
 

2fast4u_evinrude

Petty Officer 2nd Class
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Jul 19, 2010
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Re: 5 seconds @ 5000Rpm safe for 3.0L ?

Thanks Coolguy, maybe ill give that a try and see. If this dont work out for me what other props you guys recommend? 3 blade, 4 blade? Make & pitch? Boat is a 93 17 foot Maxum open bow 3.0L 135Hp. We mostly just cruise the lake and once in a while have a tube or a wakeboarder.
 

nitrosteve

Petty Officer 2nd Class
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Jul 19, 2009
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Re: 5 seconds @ 5000Rpm safe for 3.0L ?

Post up how it runs as far a speeds go once it shifts. I have a very similar boat just curious of the performance.
 

2fast4u_evinrude

Petty Officer 2nd Class
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Jul 19, 2010
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Re: 5 seconds @ 5000Rpm safe for 3.0L ?

When I hit wot i rev at about 5000rpm traveling at 28 miles per hour then once the prop shifts I get about 35-38 depends on my trim level
 

fishrdan

Admiral
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Jan 25, 2008
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6,989
Re: 5 seconds @ 5000Rpm safe for 3.0L ?

I wouldn't want the 3.0 shifting at 5000RPM, play with the adjustment screws and try to get it down. Personally, I'd want it shifting at the low end of the WOT range, maybe 42-4400RPM tops? If there is enough adjustment range, maybe have it shift once the boat is well up on plane, 3500RPM?. I've never had a shifting prop, but do know I wouldn't want to be spinning the engine over the recommended WOT range.
 

2fast4u_evinrude

Petty Officer 2nd Class
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Jul 19, 2010
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Re: 5 seconds @ 5000Rpm safe for 3.0L ?

I talked to the previous owner of the boat and he says he has it set for 6 people plus pulling a wake board. There was only the two of us on there last time so maybe thats why? I was thinking maybe leave it as is and buy a second prop just for cruising around. Just gotta figure out if I should buy a 4 blade or a 3 blade?
 

steelespike

Supreme Mariner
Joined
Apr 26, 2002
Messages
19,069
Re: 5 seconds @ 5000Rpm safe for 3.0L ?

For just cruising a 4 blade Solas Amita will give good hole shot, stay on plane with less throttle,handle better on plane and at the dock.
 

2fast4u_evinrude

Petty Officer 2nd Class
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Jul 19, 2010
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Re: 5 seconds @ 5000Rpm safe for 3.0L ?

What would be a good prop size on that? 14x20 or something like that?
 

2fast4u_evinrude

Petty Officer 2nd Class
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Jul 19, 2010
Messages
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Re: 5 seconds @ 5000Rpm safe for 3.0L ?

Theres ususally just the two of us. But when I get the tube and the wake board out there about 7 of us
 

rallyart

Lieutenant Junior Grade
Joined
Jun 7, 2008
Messages
1,184
Re: 5 seconds @ 5000Rpm safe for 3.0L ?

When I was young we got a boat with the Merc 470 inline four. The boat was propped wrong from the dealer and it spend two years running up to 5600 RPM because nobody checked what the max RPM should have been. It was 4800. The engine now has around 3000 hours on it and does blow a bit of smoke.
Unless Mercruiser cheapened their construction a lot since 1980 I think you'll be fine.
 
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