Prop Question ... What Pitch Merc 40HP

[John Glaser]

I own a 2001 PT 175 xt and noticed I am topping out at 4800 RPMS as opposed to 5500 RPM's on a Merc 40HP. I was told that I was over propped...I cannot read the pitch on the prop but was wondering whta I should replace this with ???

Folks thanks for all your Help,

P.S. Tee, I responded to your answer on my last post ... If you have a chance

Woody

 

[TOMMY RICH]

Which post? I'm lost:huh:

 

[Jim in VA]

Hey Woody!



The stock prop on my '03 Merc 40hp was overpitched as well. I was running about 4800 and seemed low to me. Can't remember what the stock prop was in terms of numbers (I think it was 14), but I have an old receipt for a new prop that I got from iboats.com and the new one was a 10 3/4 x 12. That helped a lot in terms of holeshot and I didn't notice a decrease in top end at all (not that I was getting much to begin with at a whopping 25mph!). I'm now running at WOT and full trim about 5500 to 5600 rpms (max rating for the Merc 40hp ELPTO two-cylinder). Top speed is still about 25mph.



The prop was a Hustler brand with the separate hub and housing. I liked the separate hub/housing a lot because I ended up dinging the heck out of the prop in some shallower water on the Potomac (wasn't paying attention!) and replacing the housing alone was cheaper than having it repaired! Been going strong now for a couple of seasons without issue.

 

[TOMMY RICH]

You should see about 30 MPH..

 

[Jeff R.]

I have a 40 on my PT-175 also. I switched the stock 14 pitch prop to a 12 and it made a huge difference for me. I can now hit 5500-5600 RPM's and top out around 30 mph where before I couldn't hit 5000 RPM's or go 25 mph. The 12 should help you out.

 

[Bill McElroy]

My first outboard was a 50hp Johnson on a 16ft Alumacraft bassboat,.....it had a 13" dia prop......it would go 28mph regardless of the load!! LOL

 

[Mike L.]

Hey John,

I just checked my 2000 PC175 40hp prop..it's numbered--F10.38x14p and I GPS at 30-32MPH.

 

[John Glaser]

Wow,

I am totally confused as to why my 14p prop gets me 4800 and isn't close to 32 mph and Mikes does !!!

So, I shouldn't try a 13P? (I guess there might not be one)

Does anyone have exact numbers that I can replicate frome Mercury for a 13?

What other brands would you recommend for aluminum?

Thanks So much for your help !!!

Tee, the Pitted Salt post !!!!:wacko:

P.S. I also installed another battery and a dual bank charger that has increased the weight...

Best Regards,

Woody

 

[TOMMY RICH]

I read your reply....

Don't use the acid wash...you'll have to repolish afterword anyway.

All the Sharkhide will do is magnify what's underneath so a clean polished surface is a must IMHO.

That is a lil' more weight but, shouldn't have anything to do with not turning a higher RPM.

Ask the question to Pat Goff and give him details.

 

[Steven Yates]

I have a 13 pitch prop that came on my 50hp mercury I changed my prop to a 14 pitch stainless and the 14 pitch is about all my 50 will handle, so I think a 13 would be about right for a 40hp or maybe even a 12 pitch, anyway my 13 pitch says 10.5x13P and it has 13 splines, hope this helps.

 

[William H. (Bill) Barham]

I copied this from what I wrote in the Boat Performance section. I don't know what my prop pitch is but it is the stock prop that came on my PT-17 with 40 HP Force/Mercury motor. I've gone through all of the paperwork I have and it doesn't say what prop came on it. I'll try to get out there tomorrow and see if I can read anything.



Notes/Setup: Bought used August 2003 with a 40 hp Force motor. With the standard prop and a full load; two grown men, 3/4 tank of gas and loads of equipment, at 5100 rpm I am running 29 mph. Jumps out of the hole and on plane instantly.



Good Luck,



Uncle Billy