Putting a 75 on a 2006 Pro Crappie

[Jason S2]

Hi all,



I got a ridiculous deal on a 2007 Mercury 75HP EFI 4 stroke (It's a Merc program motor that was used for about 2 months) I wanted to put a 50 or 60 on my 2006 Pro Crappie, but the cost of this motor was about half what the dealer wanted to charge me for a 50!

I would like to put it on my pro crappie, but there's one thing that holds me back, The motor is 399 lbs, the PC has a plate that says it was designed for a maximum engine weight of 310 lbs. That's a wee bit over!

Now both dealers I have talked to say they have never even heard of someone putting a 75 on the back of a Pro Crappie, but I see some of you on here have them (though I bet they are the lighter 2 stroke). Strangely enough, the dealer specs have the prop listed for a PC with a 75 Optimax 2 stroke, and the PT175s are sold with 75s on the back of them. Is the engine design weight just a function of the center of balance?

I have done a couple things that make a difference, this boat is used for trolling and catting, there's no trolling motor and there's no 50 lb trolling motor battery in the back, and you can't use the rear top seat peg because the T bar for my rods is there

Two of my buddies stood on the back by the motor (200 lbs each) and we still had a few inches of freeboard with the 25 HP on the back. Whatdaya think?



Thanks,



-Jason

 

[TrepMan]

Jason - I had a 2000 Pro Crappie with a 40 Merc, and Loved her. Before I bought my Nitro, I was seriously considering upgrading to the 75 2-stroke for more power, i'd be a bit wary of that much weight, and i've heard the 4-strokes are really tough to prop on a smaller boat so ensure A) the transom will handle it, B) insurance will cover it and C) has anyone done it so it will get out of the hole if propped right?



And if it all works out, I gotta see a pic of that motor on the boat!



Good luck!



P.S. Just checked and they've since downgraded the Max HP for the 2008 PC 175 to be a 60 4-stroke, don't assume they changes the transom so i'd say that 75 is too heavy. I know the earlier 175's had a 75 hp capacitiy.

 

[Greg Meyer]

One big concern I would have is exceeding the "plate" specs as it relates to insurance issues. If you exceed the plate you might give an insurance company an "out" if something came up...



But, I do bet that rig will "fly!"...

 

[Jason S2]

Sigh, sometimes a good deal really isn't. I just looked at the USCG plate and missed the other plate, sigh. However, it's still a rediculous deal, and as my next message will show, there's a way both me and someone else on this board can be happy!

 

[Dan J.]

Don't forget that even though hulls may be similar, the USCG level floatation requirement is fixed on load. Different configurations on the same hull (weight) will change the amount of added floatation and level float capability. Overpowering the hull against the plate rating is not a good choice, particularly on lighter, smaller aluminum hulls. IMHO

 

[Jason S2]

The 75 *IS* within the HP rating on the USGS plate, and with that engine I would have 600 lbs of load left. There is a sepaarete plate that says the boat was designed for a maximum motor weight of 310, so I would be over by 90. I sat on my current engine today, which made the wieght amost exactly the same and still had a lot of freeboard left. Still, if one of you PT175 owners (this motor is sold as an option with them) would like to swap your 50 with me, check out my post in the Swap&Sell.

 

[Dan J.]

The HP is within the rating, however, the four stroke weight is not. The weight of the four stroke at the transom puts too much weight aft to pass the level float requirement of the USCG. (The additional 90 lbs. weight stern.) That rating is set at full load (max payload) in a fully swamped condition while remaining level surface float. The Pro Crappie and the Pro Team share similar hulls, but that's where similarity ends when you look at the floatation capability of the two. The PT has larger filled deck space with a considerably larger amount of styrene floatation molded in, hence the higher rating.



Good luck in your motor swap. I thought you might want to know the reasoning on this application.

 

[Kim Becker]

Dan J. Thats good stuff. Always wondered what all went into the formula for capacity weights. Very good info. Thanks for sharing.

 

[Jason S2]

That is good info Dan, thanks! So let me see if I understand, the weight you see on a plate is what you can have and still have the boat float level? What do you mean by "fully swamped", do they put 1050 lbs in them, and then flood the boat? Does the styrene only come into play when the boat is flooded? It should make sense to me today, but I've been on the boat all day and am sorta fried. :wacko:



I hope someone takes me up on that swap, everyone would win, they get a nice big motor and it costs me less than it would to buy a 50 used.

 

[Jason S2]

OK, I found this wording on another site:

Basically the minimum requirements are that each boat must have enough flotation to keep any portion of the boat above the surface of the water when the boat is filled with water and loaded with weights to simulate submerged Persons Capacity, submerged Machinery Weight and submerged Dead Weight (the latter bringing the total load on the boat up to the Maximum Weight Capacity)

The only thing I see wrong with this is...don't people float? I have no intention of being a submerged person! If the boat is flooded, I'm out!

 

[Greg Meyer]

On big open water... you are wise to stay put inside the fgloating hull... You do not want to get separated from something that is much more visible than you are alone... A floating person alone is very, very hard to see. The silhouette of an outboiard cowling, even one floating lower in the water, is so much easier to spot. If you get out, you could get separated from the boat. Stay Put!

 

[William H. (Bill) Barham]

I'll have to look tomorrow when it's light but the only plate I remember is the one that says rated for 75 h.p. and I believe there is a total weight limit on it but I don't remember what. I sure would like to try that 75 on my PT-17.:wacko:



I've gotten a lot of really good information on this thread though..



Uncle Billy