2004 40 ELPTO Need Prop size Merc

[heffy]

I cant find the right prop for my boat. The prop reads 48 7313 8 A40 14P
Any ideas?

 

[Silvertip]

Re: 2003 40 ELPTO Need Prop size Merc

Re: 2003 40 ELPTO Need Prop size Merc

Don't understand that you can't find the correct prop. The one you have is correct (or at least close to correct). That's a 14 pitch Merc prop. If you have a very light boat, that prop is probably ok. If you have a heavier boat then a 13P is more common on the 40/50 HP ELPTO's. Right here on iBoats is about as good a selection of props as you can find anywhere. Or if you want an exact replacement for what you have, take that number to your Merc dealer.

http://boatpropellers.iboats.com/Me...andard&**********=681448449&*******=380531377

 

[steelespike]

Re: 2003 40 ELPTO Need Prop size Merc

Re: 2003 40 ELPTO Need Prop size Merc

That is a merc number the important part 14P is 14" pitch if you have the motor model and year you can look it up here.
If you can tell us the type/size of boat,max rpm and speed we can help refine your choice.Also your typical activities and load will help.
Check out the Turning Point props.Stainless performance at aluminum prices.

 

[heffy]

Re: 2003 40 ELPTO Need Prop size Merc

Re: 2003 40 ELPTO Need Prop size Merc

Thanks guys. My boat is heavy. 14' crestliner with a steering column. I hit a rock in Canada last year and the local marina sad that I should have a 14p instead of what came with the boat. I think it was a 13P, MAX rpm is 5000 to 5500. I fish with 2 sometimes 3 guys.
One person in the boat I can get it up to 42 MPH

 

[hwsiii]

Re: 2003 40 ELPTO Need Prop size Merc

Re: 2003 40 ELPTO Need Prop size Merc

Heffy, something is wrong with your numbers, That boat can't do 42 MPH with a 14" Pitch and a 2 to 1 gear Ratio turning 5500 RPM. That would be a -15% Slip and that is impossible. At 0% Slip it can only do 36 MPH. 32 yes and that would be at 12% Slip, which is normal for aluminum, 42 MPH NO.

H

 

[Silvertip]

Re: 2003 40 ELPTO Need Prop size Merc

Re: 2003 40 ELPTO Need Prop size Merc

That motor doesn't have a 2:1 gear ratio -- it has a 1.83:1. Without running the numbers, I also feel 42 MPH is a stretch having owned similar boats in the past. 32 - 35 MPH is possible however. It is all a moot point however. If the tach reads 5500 at WOT then a 14P prop is correct.

 

[heffy]

Re: 2003 40 ELPTO Need Prop size Merc

Re: 2003 40 ELPTO Need Prop size Merc

My lawrence fishfinder X51? reads 41 42 MPH empty. If I remember my speedometer on the consol read the same. I have a GPS for my car I will check it with that next week.

What will I notice between a 13P and a 14P 13 will get me up quicker and a 14 will have a quicker top end?

Thanks

 

[hwsiii]

Re: 2003 40 ELPTO Need Prop size Merc

Re: 2003 40 ELPTO Need Prop size Merc

Yes give us some real MPH and RPM, then we can tell you. Even at 1.83 gear ratio it is still showing a -5% Slip, which is still not right. Heffy can you tell us what gear ratio you have for sure.

H

 

[Silvertip]

Re: 2003 40 ELPTO Need Prop size Merc

Re: 2003 40 ELPTO Need Prop size Merc

It's not a matter what a 13P will do. If your rpm is correct with a 14P, 13P will be the wrong prop as it will raise rpm another 150 - 200 rpm so you now over rev. It would be better for the engine when the boat is heavily loaded but not good when lightly loaded. I really doubt you are going 42 MPH.

 

[heffy]

Re: 2004 40 ELPTO Need Prop size Merc

I went to the local Mariana last night to talk to them. Some Idiot wanted to sell me a 12P He said becarefule not to over reve the motor. Ill find out tonight the gear ratio.
Thanks

 

[Silvertip]

Re: 2003 40 ELPTO Need Prop size Merc

Re: 2003 40 ELPTO Need Prop size Merc

Actually, there is another ratio for the 60 Mercs and that's a 1.64:1.

 

[heffy]

Re: 2003 40 ELPTO Need Prop size Merc

Re: 2003 40 ELPTO Need Prop size Merc

Ok Guys you are right. I had my GPS on the lake and it was reading about 6 mph less then my Fish Finder. Top speed was 35 to 36 with the 14P prop
Thanks for your help

 

[Silvertip]

Re: 2004 40 ELPTO Need Prop size Merc

The prop you should be using is the one that allows the engine to rev at the top of the manufacturers recommended rpm band at wide open throttle. If that number is 5500 RPM and that's what you observe on the tach at WOT with what you consider an average load, then that's the prop you need to use. More pitch than that and the engine begins to lug which is not good for it. Too little pitch and the engine over revs which is also not good for it.