Sea Ray BR 210 prop selection problems

[cptnmcluvin]

Howdy,

I'm having trouble getting the correct prop for my 2000 Sea Ray BR 210.
The boat specs are:
- 21 foot bowrider
- 3,400 lbs dry weight
- 8 foot 6 inch beam
- 21 degrees of dead rise at the transome
- Mercruiser Alpha One with a 1.62 gear ration
- Stock Mercruiser 5.0 liter EFI V8 engine with 240 Horse power

This Sea Ray came with a 19 pitch Mercury Vengenance #48 16316 stainless steel prop. This prop had good hole shot but rpms were way too high at crusing speeds. The 5.0 liter V8 was turning over 3,500 rpms to push the boat just 30 mph.

We switched to a 21 pitch by 14 inch diameter Stilleto #10321 stainless steel prop. Now the boat cruises 30 mph at around 3,100 rpms but hole shot is greatly diminished. The 21x14 prop has trouble staying on plane and maintaining speed when pulling wake boarders and skiers.

We use the boat for wake boarding, slalom skiing, tubing, and cruising.

What are the best prop options for this type of boat?

Would a 4 blade prop offer any advantages?

Thanks,

John

Richmond

 

[Maclin]

Re: Sea Ray BR 210 prop selection problems

Two pieces of information that will help any advice given to be more relevent are 1.) Top RPM the engine can reach at WOT (wide open throttle) with one of the props. 2.) The MPH acheived at the top RPM. Just watch the RPM's to not over-rev if it acts like it can go past 5000rpm.

The engine needs to be able to reach the top RPM in it's operating range in order not to be lugging all the time. If you can give us the top RPM and MPH at WOT then a proper pitch for your boat with that engine can be determined.

 

[jestor68]

Re: Sea Ray BR 210 prop selection problems

One thing that it takes boaters a while to understand is that one prop(size) cannot necessarily do everything you want to do with the boat.

For economical cruising, you want a prop with more pitch, to lower the rpm; not caring so much about strong acceleration.

For water sports, you need a prop with less pitch for good acceleration, which will necessarily raises the engine speed(rpm) across the entire speed range.

Most of us end up with two props; one for "off season" cruising around, and one for summer water sports, often referred to as the "ski prop". In this use, the 4 blade prop really shines. It usually provides better acceleration, better speed holding, and smoother operation compared to a 3 blade. You do not need an expensive SS prop in this application. The Quicksilver and Solas 4 blade aluminum props work great for water sports.

The WOT operating range for your motor is 4600-5000 RPM.

 

[cptnmcluvin]

Re: Sea Ray BR 210 prop selection problems

Jestor68,

That's great advice.

Our purpose is to improve the boat's skiing and wakeboard towing abilities.

Sounds like the 4 blade 20 pitch is what we want.

I shopped a little online and found 2 Michigan Wheel props that might work.

1. Michigan Wheel Apollo Stainless Steel 4 Blade 20 pitch for $314 plus a $33 hub

2. Michigan Wheel Vortex XHS Aluminum 4 Blade 20 pitch for $150 plus a $33 hub

Now, we'll need to think about stainless steel versus aluminum. The $174 difference is a lot money.

Sure would be nice to demo one before making the decision.

 

[Maclin]

Re: Sea Ray BR 210 prop selection problems

What is the WOT RPM and MPH your engine can reach now? Hard to decide what pitch is good if those two pieces of info are unknown.

 

[NHGuy]

Re: Sea Ray BR 210 prop selection problems

Yes, report the max rpm and boat speed of the props you currently have. It sounds to me like they might already be correct. Maybe just get a floating prop wrench and an extra prop nut/washer/keeper set.

 

[QBhoy]

Hi
apart from as others have said...I might add that 30mph probably isn’t the ideal cruising speed. It would surely be in the mid 20’s and be very happy on plane at that ?
I haven’t checked but I think the earlier suggestion for your rpm range being 4600-5000 might be for an mpi and not an efi. I’d think that’s more likely to be 4400-4800...
Anyway. Get rid of that silly vengeance. They time after time prove themselves to be worse performing than the black max. Not the the black max is rubbish. Just that what’s the point in a vengeance if it’s of the same cut and only much heavier. It has yet to show an improvement over the same ally black max on any boat I’ve tried it on.
The real answer sounds like you need a good prop of either a 19,21 or better still, a 20”...if the above pics were taken using the 21” prop you have. Stick to the known good merc props like tempest, mirage, laser 2 and enertia and your won’t go too far wrong.
if you go for a tempest plus or mirage. Be aware that their larger diameter can have an effect when thinking pitch for pitch.
Good luck.