500r air entrapment cat

[XXX Notch]

So this has been discussed some on the facebook page but I'm getting so many different opinions i thought id bring it up here for more opinions and info before i make a decision on direction from here.

Thanks to some great info i have learned that my sport master r does NOT have a cambered skeg so I'm sure that its contributing to the torque steer at high engine heights in turn its causing me to constantly turn the wheel left to go straight mid 80s and above. that being said it seems as the constant turning the wheel left to go straight over an extended period of time is in my opinion heating up the mercury HD power steering and i will loose steering (just goes very stiff) unless i lower engine and slow down then it comes back. That being said if i make a hard run right after engine is up to temp i do not get the loss of steering but will encounter prop walk in the low 90s that is causing me to back out to save myself from trouble. Mercury Racing is telling me im running to much prop and having to run extreme heights to get rpms where i want and in turn creating to much torque that the power steering cant handle the load. My issue with that response is that how can i be running the prop to high because of pitch that it continues to pick up mph as I'm bumping up engine plate at least to the point it prop walks a scares me lol. I mean if that's true then i can really foresee some issues when running a CNC and fully surfacing this thing. so for me the question is do i need to put a torque tab on this lower since the cambered skeg is not an option because of cost and test to see if that helps the torque steer and in turn if it fixes torque steer and i don't have to continually turn left and heat up this power steering to failure or am i indeed running to much prop and all issue would go way running smaller prop lower in water to get mph and rpms I'm after. I have watched probably every ES Customs Video on the interwebs and don't see any of Erics boats torque steering or anyone talking about the Mercury HD power steering giving issue at extreme engine heights so is it an issue with my equipment or my lack of experience to know what contributing factors are compounding and giving me these issues.

sorry for the long winded post just trying to describe things as best as possible

[NICE PAIR]

Take a look @ the eighth article on this page "What is the best prop for a single cat outboard" there might be some help for you.
Back in the day, when we used to run single engine cats we did have boxes of props to get to where we wanted to be. You might want to tell peeps what size and brand of boat you are trying to make run. Re-reading your article could you put a oil cooler in your power steering set up to alleviate one of the issues.

[XXX Notch]

Thanks I’ll check that thread out

Boat is a 24ft Turner Savage

[NICE PAIR]

Nice Rig, right hand prop ???

[XXX Notch]

Yes sir running a BBlades 28 max 5 currently

[NICE PAIR]

You seem to have a couple things to fix, I think since its a single, I'd start with a steering wedge on the skeg. Is the prop new, the BBlades peeps might answer some questions about the issues are having in regards to diameter, pitch, amount of blades. Are the a lot of 24' Savages running 500's? Has Eric been any help?

[KIRCHNER]

i had a similar problem, i formed two epoxy wedges on the rear edge on sponsons, pushing the stern to the RIGHT, did the trick. now a pleasure to drive at 80, tracks absoultely straight. hands off the wheel.

[XXX Notch]

The Savage is a new build from Turner, i think im #4 and the only with the 500r so far so in reality I'm jumping into a new hull and doing the testing myself to find what works and what doesn't and I'm cool with that as i like to learn and experiment the process. Alot has been learned and fixed thru prop testing and now I'm down to these things to find what's gong to work for me in the end. I would love to pick Erics Brain but don't wont to waste any of his time with things as its not his Baby so to speak. My next Boat WILL be a Simmons that i can say with certainty. BB Blades has done fantastic getting me to this point and I'm feeling like before anymore prop work is done i need to resolve the issues at hand because I'm certain there is more mph here just need to resolve the handling issues. I'm really surprised Mercury racing says the cambered skeg wont make much difference and i don't know if i agree with that statement as i kinda feel like they may be covering up the fact that they sold the wrong lower unit to Turner with Turner not knowing any better because this is new territory For Turner but that's just my opinion on the answer from Mercury. others are saying the cambered skeg is the fix for these issues so im gona try a torque tab and see where that gets us

[XXX Notch]

i had a similar problem, i formed two epoxy wedges on the rear edge on sponsons, pushing the stern to the RIGHT, did the trick. now a pleasure to drive at 80, tracks absoultely straight. hands off the wheel.

This is very interesting, could you share some pics of what you did?

[OnPad]

I will preface this post with the fact that I have no experience with a engine so large mounted to a boat.

A few ideas that are streaming through my noggin.
1: Torque tamer, or a cambered skeg is pretty much mandatory on a fast single outboard. 2: Smaller diameter prop, or one that has less blade area at the tip, ( cleaver, or drag) is usually more drivable at high speed. 3: Just a thought, but maybe Mercurys power steering isn't up to the task.

There is also things that can be done with aero, and hydro dynamics that help, but is pretty involved, and better designed into the boat then a after thought . I have a rc tunnel that has aero down force on one sponson, and lift on the other. It also has anhedral in one sponson, and dihedral in the other. This is a trick that unlimited hydroplanes, and model boats use. As the boat twists up it dries out, versus creating drag on the loaded sponson.

[XXX Notch]

yes agreed. I'm going to test some epoxy (jb weld) and build a torque tab to test out. i don't want to weld or drill holes just yet on such an expensive lower unit as i have already had the first sportmaster r replaced under warranty lol

[OnPad]

I forgot to say,.. that boats a beauty. Looks like a great fishing platform.

[XXX Notch]

I forgot to say,.. that boats a beauty. Looks like a great fishing platform.

Man thank you, it does fish really well. I'm enjoying the hell out of it

[KIRCHNER]

This is very interesting, could you share some pics of what you did?

ill tryfor pics. i dont think the skeg will help imo. thinking back you could buy 2 t tabs, sand the gel and JB them to the port side edges. pushing the stern to starboard. before the tabs, when i backed off at high speed, my bow would swing to the left, where it actually should be under full power, its called crabbing. ArtK. xxx noted the steering stiffens up, and has to back off, my skater does the same thing,its not the steering, its torque. boat gets into this ''zone'' and feels locked. still an issue for me

[David]

If you buy a new case with a cambered skeg, can you recoup some of the cost by selling your current lower? You might be risking blowout with your gearcase crabbing through the water.