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  #11  
Old 08-11-2009, 03:46 PM
cobiawayne cobiawayne is offline
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Default Re: stern heavy

ok just measured my leading edge of lower unit is 40 inches back from transom and cav plate is 4 inches up.will try to post pictures
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  #12  
Old 08-11-2009, 03:51 PM
Bushwacker Bushwacker is offline
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Default Re: stern heavy

I'm running a 30" setback bracket and my cav plate is 3.5" above keel. I run a Doelfin and a 4 blade prop for extra stern lift. Low speed planing performance was terrible until I tried a 4 blade prop; will now plane at 12 mph!
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  #13  
Old 08-13-2009, 06:04 PM
Bigshrimpin Bigshrimpin is offline
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Default Re: stern heavy



I think something like this would help a bunch. I can plane at low speeds with my bracketed seafari, but it's still light in the bow at speeds even with a Mirage Plus or Rev 4.
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  #14  
Old 08-13-2009, 08:40 PM
McGillicuddy McGillicuddy is offline
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Default Re: stern heavy

Take note about ESD's point about the motor height relative to setback. 1 to 1-1/2" is for the transom mount. Armstrong bracket calls for raising the motor 1" for every 12" of setback so at 3.5 - 4" you're probably close now.. might need drop one more hole.

Another issue is your Laser II prop - its probably the wrong prop. You have a prop with a lot of rake that gives you more bow lift than you want.

You might try to borrow a Black Max (3-blade sternlifter) or a if you can, an aluminum four blade like the Alpha from a shop or somebody. I all but guarantee your hole-shot will be cut in half and you'll greatly reduce that bow rise while running. If the Black Max works you can get it from PowerTech or Propco in stainless.
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  #15  
Old 08-15-2009, 09:54 PM
cobiawayne cobiawayne is offline
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Default Re: stern heavy

thanks guys i raised the motor up one hole and it seemed to ride better in the river,however i took it offshore today and whenever the boat would come off a wave (2 to 3 about 6 seconds apart)it would dive to port abruptly, dangerous!When I got home I started trying to figure out what was going on and i discovered my torque equalizer was missing could that be the problem?
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  #16  
Old 08-16-2009, 01:36 AM
McGillicuddy McGillicuddy is offline
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Default Re: stern heavy

If you're referring to the little trim skeg as absent, a 200 Merc 2-stroke definitely creates considerable steering torque especially w/o hydraulic steering. The tab won't solve your porpoising but it may help counter that dive to port quartering a swell...those little tabs have amazing influence, the final say you might say, almost like a second rudder
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  #17  
Old 08-16-2009, 09:24 AM
cobiawayne cobiawayne is offline
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Default Re: stern heavy

when you say black max prop,i have a 1981 black max 150 with a 3 blade alum prop.is this the prop you are talking about.
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  #18  
Old 08-16-2009, 01:34 PM
McGillicuddy McGillicuddy is offline
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Default Re: stern heavy

It may be. The Black Max was a motor name given to some of the Merc V-6s.

The Black Max propeller is an aluminum prop designed for aft heavy apps like stern-drives, good chance that one came with that 150. It is a classic blade that offers unmatched stern lift in a 3 blade. It has very little rake and cupping and is easy to turn.

Quicksilver's equivalent prop is called Black Diamond. My understanding is that the prop used to be available in stainless...

I believe Propco still makes them in stainless and PowerTechs MQF and MQS (MQS for your motor) series are also the same shape with slightly different pitches.

The Black Max is everywhere for around $100 -130. Chances are that your other prop is just that. Swap em out and see but be careful that you don't over rev as the prop on the 150 likely has a lower pitch than the Laser II but if its a 19 pitch and compatible, try it out. And definitely get a trim anode on there. Good luck.
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  #19  
Old 08-16-2009, 04:33 PM
Fr. Frank Fr. Frank is offline
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Default Re: stern heavy

Those little tabs are called torque tabs for a reason.
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  #20  
Old 08-17-2009, 02:02 AM
eggsuckindog eggsuckindog is offline
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Default Re: stern heavy

I agree that Lazer is probably not a good fit for you
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