Prop Mercruiser 135 - 2007

[enn858]

Hi

I have a Bayliner 175 BR w Mercruiser 135
Top speed (gps) 45 Mph
WOT rpm 5050
Standard propeller 21`

I use the boat for cruising, not much for pulling skiers etc. but for rather long cruises on a huge fresh water lake

i have checked appcenter.mercurymarine.com/propSelector/

And it recomends a Mercury inertia 13,5x22

My Q

1) is this a propeller you would recomend?

2) my boat is standing winterrised 400 km away at my summerhouse - so is my org. mercruiser manuals and i dont remember if it is a rh or lh rotating prop - it is a standard mercruiser 135 w alpha 1 gen 2 yearmodel 2007

 

[walleyehed]

Re: Prop Mercruiser 135 - 2007

I'd say the merc selector is real close..the E7 will turn about 150-200 more RPM in the same pitch, so I'd bet the 22 will do pretty good.....in the Enertia.

 

[enn858]

Re: Prop Mercruiser 135 - 2007

Thanks

But should i take a 22 or 23?


The boat is as i write used for longer day trips with 2 persons on board and reaches 5050 rpm (sometimes 5100 rpm) max is 4800.

I want to be able to run with 2 persons wot at 4800 or sligtly over - in all my previous boats they seems to run best slightly underproped.

The enertia model should give 200 rpm more (=5250-5300 rpm) and 1`pitch more should give - 300 prm so all in all i should get around 4950-5000 rpm WOT right?

 

[walleyehed]

Re: Prop Mercruiser 135 - 2007

Yea, I think you'd be in the 5000 range.
a 23 may be closer to 4800, but I'd verify the tach before spending money on a prop like that...If this is a brand new rig then you're likely OK.
Your std 21...is it aluminum?

 

[enn858]

Re: Prop Mercruiser 135 - 2007

Yea, I think you'd be in the 5000 range.
a 23 may be closer to 4800, but I'd verify the tach before spending money on a prop like that...If this is a brand new rig then you're likely OK.
Your std 21...is it aluminum?

Tac is verified, boiat and engine has just passed 20 hours (and has just performed first service)

Standard propeller is Aluminium (standard Mercruiser alu propeller)

 

[walleyehed]

Re: Prop Mercruiser 135 - 2007

OK, the std prop is a black max and the efficiency of SS will be much better.
Let's take a shot here..let's take 200 RPM for 1" pitch, let's take another 100 going from alum to SS...... 300 drop total (theory).
We might gain 150 back with the Enertia in 22. 4950-5000 WOT. The 23 may take 200 off and put you (in theory) in the 4750-4800 range.
As long as your test-runs are with a normal load, those numbers would show a 23 falling into place.
Best cruise will "probably" be with the 23 in the Enertia.
For best efficiency, fuel-wise, being set-up for 4600-4800 would be the lowest you'll ever want to go. If you get much below 4800, your hole-shot will start to suffer compared to how it is now.

 

[Crownie2]

Re: Prop Mercruiser 135 - 2007

OK - I will relate my experience with my 20' Crownline bowrider:

Stock prop was the same as yours - 21" Black max.
I switched to a 21" Enertia and the rpm's stayed the same or went down very slightly. Based on that I would guess the 22" would be great for you.

Keep in mind that while the Enertia is a great cruising prop is was designed for larger loads and your hole shot would probably suffer, if that matters to you.

Another option would be a 21" Laser II - and it costs less.

Don't get me wrong - I love my Enertia - I gained 4% - 5% in speed through much of the RPM range - so it is a very efficient prop...

Bob

 

[enn858]

Re: Prop Mercruiser 135 - 2007

Thanks all.

Your input made it easy for me to make up my mind - i will go with a 22`enertia - i like the idea of beeing sligtly underpropped - and have the reserves for the days where we are more than 2 in the boat.

Will buy one on e-bay leter today

 

[enn858]

No Subject

No Subject

 

[Crownie2]

Re: Prop Mercruiser 135 - 2007

My thinking too...

They come with the PVS system and you will more than likely want to open them up somewhat - but I would stick with the solid (plugged) hole for awhile.

Bob

 

[enn858]

Re: Prop Mercruiser 135 - 2007

Just wanted to inform you all taht
My new enertia arrived today (from Short's Marine Inc - E bay) it for shure has another blade shape than what i have ever seen before - cant wait until May where the ice is gone on my lake - i wonder if i gain any top speed with this new propeller?.

Another thing - it is perfectly machined and polished - infact i have newer seen another SS propeller that is PERFECT - not a single casting mark etc.

The enertia is much heavyer than i had expected - but i guess the Alpha drive is made for it so i shouldent have to worry.

The best part is that by ordering it in USA and have it shipped here i saved 40% compared to wholesale prices here in Scandinavia.

 

[walleyehed]

Re: Prop Mercruiser 135 - 2007

The Enertia is actually about the lightest SS prop made compared to another for the same application.

 

[engine31]

How do I measure the prop size

How do I measure the prop size

I know this is a dumb ? I have been a boat owner for 10 years and have only had my prop rebuilt, unitil now that is.. I want to get a SS Prop for my runabout how ever I am not exactly sure of the size or how to measure. My boat is an 18.5' 135 HP Alpha 1 1995

 

[walleyehed]

Re: Prop Mercruiser 135 - 2007

Engine31, go ahead and start a new topic at the top of the prop forum and we can keep these 2 threads apart to lessen the confusion...when you start your new topic, list the WOT RPM and what prop you currently have..make, model, etc...