4 Blade versus 3 Blade

[LennyB]

Hi Guys,

I'm thinking about purchasing a 4 blade prop to replace my 3 blade and just wondering if there is a noticeable difference to justify the investment. My stock 3 blade is great in calmer conditions but I'm hoping the 4 blade will get a better bite when navigating bigger waves. To the guys that have ran both on their rigs, can you tell a big difference as far as torque and slip or is it marginal?

[Lightningboy]

3 vs. 4 blade props is more about overall performance, rather than keeping a grip on the water.  Each has it's advantages & disadvantages.

A 3 blade will spin up faster on holeshot since there's less rotating mass.  A 4 blade takes more torque by the motor to get you out of the water.

But a 4 blade can be much better at speed depending on the weight balance of your rig.  Stern heavy boats will get more lift out of a 4 blade, helping them run at speed.  I run a trophy+ since my TR21 is a little stern heavy, especially with the 3 L motor.

Try one out; you might like how it drives.  Swapping props can really change the handling of a bass boat.

If you want to really improve your grip in heavier waves, you can't beat a hydraulic jack plate.  You can lower the motor to keep the prop deeper in the water.  I'd never be without one again.

[Revtro]

After running both, I also went with a Tophy Plus because of the ability to control the venting with removable vent plugs.  Changing the venting will make a huge difference with your hole shot.  My boat is also a little stern heavy and I found that the rear end of the boat slips around a whole lot less with the 4 blade.  IMO it hooks up a lot better in the rough stuff than a 3 blade.  It made a dramatic difference.

[Waterfoul]

I've recently been trading back and forth between a 3 blade and a 4 blade on my Triton TRX 186.  The 4 blade has so far has cut my time to plane in half (or better) and added 4 mph to my top end while running at exactly the right rpm for my Merc 150 EFI.  The 3 blade over revved by about 200-300 rpm when running by myself.  The 4 blade runs the right rpm no matter what the load is.  One word:  Efficient!

It also seems to handle a bit better... turns tighter without slipping or hopping.  I haven't had it in any rough water yet so not sure how it will help there.  BUT, based on my experience racing a 24' V-bottom 10 years ago and trying about 4 different props I'd say it will do nothing but help.  

One thing that the 4 blade does that the 3 blade never does is "check" while at idle speed right after shifting into gear.  It feels like the prop is actually "bouncing" back and forth until I give it a little gas.  Has anyone else experienced this?  I've checked the prop shaft... tight.  Checked the hub... tight.   Not sure how else to describe it other than it "checks" or "chucks" a bit.  A little gas and it goes away.

[Revtro]

Hmm.  I have never had that with mine.  Weird.  I wonder if the extra torque is making your power trim shake a little or maybe the transom is flexing for a second.  Check your mounting bolts.  Mine come a little loose every year.   

[djkimmel]

One thing that the 4 blade does that the 3 blade never does is "check" while at idle speed right after shifting into gear.  It feels like the prop is actually "bouncing" back and forth until I give it a little gas.  Has anyone else experienced this?  I've checked the prop shaft... tight.  Checked the hub... tight.   Not sure how else to describe it other than it "checks" or "chucks" a bit.  A little gas and it goes away.

I have been in boats in the past that have done that. Been quite a few years. I will try to recall the things that caused that. It is something that can (and should) be 'fixed' or adjusted my vague memory tells me. I'm not sure if it was prop-related or something else though. Might just be a difference in the hub insert too? Do you have a spare? Been so long I can't remember which props have easy replacement and which ones don't?

I think the Mercury hubs can be easily swapped. I think I even recall doing it once out on St. Clair? If you have a spare, drop it in and see if the 'checking' continues. Maybe another 'old-timer' with a better memory will pipe in with an explanation. I recall this used to be more common, whatever causes it.

[djkimmel]

Hi Guys,

I'm thinking about purchasing a 4 blade prop to replace my 3 blade and just wondering if there is a noticeable difference to justify the investment. My stock 3 blade is great in calmer conditions but I'm hoping the 4 blade will get a better bite when navigating bigger waves. To the guys that have ran both on their rigs, can you tell a big difference as far as torque and slip or is it marginal?

I don't recall what motor brand and model you own? I pretty much always had better Great Lakes / rough water performance and sometimes general performance with the right 4-blade, and on some boats a 5-blade, prop in the past with the other brands. I recall being in quite a few rough water rides that were horrible to almost couldn't get 'er done in the old days with people who had 3-blade props up too high. Lots of blow out. Lots of performance issues. I believe, in general, a lot of that has improved over the past 10 to 15 years but still talk to too many Great Lakes bass boaters who claim better performance from 4-blades. I even still see a 5-blade prop once in a while.

My Yamaha VMax HPDI 225HP is a different animal though. When I bought it, they gave me a 3-blade prop they said was specifically designed to maximize performance from the increased torque they added around my model year (2004 bought in October 2003). I have always agreed with their recommendation based on the performance in speed verses hole shot verses rough water handling. I could go a little faster if I raised the motor a little but I don't need to anymore and prefer the deeper bite since I no longer have a hydraulic jack plate on my old Ranger.

My hull is a 1993 - 1 or 2 years before Ranger increased the HP rating for that hull length from 245 to 250 - so I'm never going to compete in top end speed with the new, faster hulls anyway limited to a 225HP. I'm personally fine with that. 58 to 60 mph is good for me the few times I open it up.

If I empty out my 3 tackle shops worth of tackle (because I get bored easy), it can run 64 to 65 for a 20 year old, not loved enough, 21' 5" inch hull. Feels squirrelly to me the handful of times I've done that. I like flat and stable so I leave it at the present height, leave in the tackle for me experimentation and save a little gas and oil money by running 40 to 50 most of the time.

I really haven't heard or seen a ton of discussion on 3-blade verses 4-blade for the Etech though but all the rest outside of the Yamaha HPDI seem to run better up here on average with a 4-blade from what the bass boaters tell me or discuss. I will have to find out for the SHO. I have driven them but haven't had much discussion about props yet. Pretty sure you have something else on your boat. Just been a while since I have seen you fishing anywhere.

[djkimmel]

Ah. Read the post where you said you have the 18.5' Ranger with a 150 HP Mercury. I would definitely recommend a 4-blade for you considering your other activities (more than 2 anglers, some Great Lakes). Just find the right size for your average load and you should get a better ride. Maybe faster or maybe the same speed depending upon motor height, but you should get better control.

When I had my Merc, and a Johnson before that, I easily noticed improvements with 4-blade props once I got the right size. I have seen people mention performance and speed improvements with a 4-blade on a 150HP Merc in the past. They sometimes had to try several models and sizes to get there. You may need to go a little smaller than normal if you have a lot of weight in your boat considering the size/weight of the hull.

If you are fairly spartan with your equipment load, then you can probably get away with the larger prop and still improve overall performance. I had to go 1 size smaller than recommended in a 4-blade when I had my Merc 255 because my hull is heavy - plaque states it is 20' 1" but it is really 21' 5" from nose to end of that long extended hull and 93 492VS not rated for 250HP, I could and did carry 64 gallons of gas when I still fished tournaments and I am not known for packing my compartments lightly. That original built-in 492VS hull extension is so long that my boat is actually ~4 mph faster without the additional extension from a jack plate.

Seems like enough anglers on here have played with props that they could get you in the right direction fairly quick. Been too long for me and a 150HP to give specific advice. There has been some good discussion on here in the past about the 2 most favored 4-blade props for the Merc EFI. If I find the posts or recall for sure, I will post.