4.6L V8 propping exercise after break-in. Need to know for new 4 stroke folks.

[mikesxpress]

While you can still prop swap, the correct procedure for the V8's is after break-in you have to select the best performing propeller/jack plate & trim settings for your average running conditions (2 people, gear, full fuel, summer time, etc..). Then you get the Mercury propping software run. If your dealer didn't tell you about this, well here is the condensed version.

Mercury propping exercise.
Mercury tech onboard with his G3 laptop and you make 3-4 WOT runs. The engine run data is imported into the laptop which will provide a best parameters settings for the engine and THAT prop (demand/demand linear/air-fuel mix/etc..). Another WOT run and check it again. You now have your V8 tuned to your boat/prop. Swap props and you need to do this all over again to maximize performance.

Best to get all your settings and propeller selection/tweeking done so it spins up close to 6200 rpms consistently, and then do the propping one time and have another prop cloned as a spare. This will virtually eliminate the previous "try this Bravo"
"add 3-4 vent holes" unless you have deep pockets and your Mercury tech has lots of spare time to go to the water.....

[spider1]

Thanks for the info! This really sucks!!!!

[mikesxpress]

I think it will actually save folks time & $ in the long run. Nothing says you can't still run different props. It just won't be performance matched to the engine. Same as when folks swapped props on the Optimax but there was no way to do these type calibrations to the 2 strokes with the computer.

[spider1]

Mike I don’t see where this is a big deal with the guys that run cookie cutter boat but a real pain in the azz for the high performance guys that does a lot of prop swapping trying to get that last mph out the rig.

[mikesxpress]

Connor it's not an issue. Just keep swapping props and skip the Mercury propping. Just realize there maybe a little bit more performance left untapped when you do.

I know I have spent allot of $$$$ and time over the years prop swapping on 13 different boats trying to squeeze a little bit more performance out. On any rig, there is always one "go to" prop that is run most of the time while one spends more time/$$$$ playing with others. (Been there/done that.) I can't even remember how many solid hub/big wheels I tried on a Bridgeport that was hung on my tunnel hull Shadow back in the 80's but I know I skipped a few meals to pay for them.....

This process, if you choose to use it, just drives you to that majority run prop and gives you something we never had before which is engine tuning to your rig.

[bigboyztoyz]

What exactly is the "mercury propping" doing. Seems crazy to me to get optimal performance they need to change something in the computer?
1. What happens when running different elevations?
2. What happens with different loads?
3. What about a rough water prop?
4. What about guys who swap props based on 1&2&3 conditions?
5. Why not let the motor run WOT, give it all it can and leave it at that?
6. Wonder if the Simon tune would eliminate the need for Mother Mercury to "special Tune" B.S. (let me run my own damn motor)

[12many]

I wanna follow this see what kind of results people see. I may have it done.

be curious if I could swap larger TB from 250 on my 200 and have this done to richen fuel mix. ha ha ha..

[mikesxpress]

I'm still fooling with props for my 250 on my Ranger and recording data. I have new 23 & 24P 3 blade Fury's at the prop shop now getting tweeked. Once I'm satisfied I can sustain 6200 rpms during summer I'll benchmark that and get the propping done. Then I'll see if it actually makes a significant difference.

[Wackyjig]

That is rediculously stupid

[mikesxpress]

Have you performed this propping on a 4.6L 250 ProXS yet?
Did you (or do you) expect to see any enhanced performance from doing it?
What are the alloted hours to conduct the propping exercise and your cost per hour?

[EuropeanAM]

Mike- the information you're referring to is intended for Dealers and OEM's (isn't supposed to be published).

There is no allotted time for propping a boat.

When utilizing G3-2018 Computer Diagnostic, you are merely monitoring data to determine that the demanded throttle position and the actual throttle position are matching at 100%. There is NO ADJUSTMENT that can be made with the Laptop... the "adjustments" available are the throttle DEMAND (ie: Cable or control adjustment), OR... changing the Prop, Engine Height, or Trim Angle.

Adaptive Speed Control is not active at WOT.

[mikesxpress]

Don what your saying is the same demand/demand linear that was set for WOT and idle at the rigging phase are the only things that are checked and can be altered by the tech during the propping exercise?
If demand/demand linear is correctly set, the end users actual use can validate correct idle rpm (via Smartcraft) and that the prop selected will achieve 6000-6200 rpms then the propping exercise isn't really necessary?

[EuropeanAM]

Don what your saying is the same demand/demand linear that was set for WOT and idle at the rigging phase are the only things that are checked and can be altered by the tech during the propping exercise?
If demand/demand linear is correctly set, the end users actual use can validate correct idle rpm (via Smartcraft) and that the prop selected will achieve 6000-6200 rpms then the propping exercise isn't really necessary?

No- idle RPM is PCM controlled, there's nothing we nor the end user can do there to change it.

Demand, Demand Linear, Demand Linear w/Guardian, Trim Position and Engine RPM are the monitored items. If one (or more) items is outside of spec, then there are specific actions to take based on the outcome of the data (each item has it's own list of possible causes and actions to take).

The "goal" is 100% Demand, 100% Demand Linear, 100% Demand Linear w/Guardian, Trim at optimum setting, and Engine RPM's on target.

[Rickybobby]

No- idle RPM is PCM controlled, there's nothing we nor the end user can do there to change it.

Demand, Demand Linear, Demand Linear w/Guardian, Trim Position and Engine RPM are the monitored items. If one (or more) items is outside of spec, then there are specific actions to take based on the outcome of the data (each item has it's own list of possible causes and actions to take).

The "goal" is 100% Demand, 100% Demand Linear, 100% Demand Linear w/Guardian, Trim at optimum setting, and Engine RPM's on target

<Fixed Quote Syntax>

So is this something that has to be checked out before or after break in by your merc mechanic I haven't got mine yet so just curious so I'll know when they hang it to make sure it's at 100%

[mikesxpress]

If the goal is 100% Demand, 100% Demand Linear, 100% Demand Linear w/Guardian which is set at the shop during rigging and can be subsequently validated at the shop after break-in, then there isn't any reason one would need to do the propping exercise as long as your achieving 6000-6200 rpms and maintaining water pressure?

[flatsboy]

[EuropeanAM]

If the goal is 100% Demand, 100% Demand Linear, 100% Demand Linear w/Guardian which is set at the shop during rigging and can be subsequently validated at the shop after break-in, then there isn't any reason one would need to do the propping exercise as long as your achieving 6000-6200 rpms and maintaining water pressure?

Mike- you're not reading the process/items completely, as you cannot validate ALL items simultaneously with the boat in a static/trailered state. Must be on the water at WOT RPM's.

Traditional methods CAN still be utilized. They're just not as straightforward.

Oldtimer57... The information I've provided is available in the INSTALLATION INSTRUCTIONS that come with the engine, in the crate. Also available in Service Manual and in a Service Bulletin. That's about as public as it's going to get, for most technical information.

[mikesxpress]

OK.

[ron green]

If the goal is 100% Demand, 100% Demand Linear, 100% Demand Linear w/Guardian which is set at the shop during rigging and can be subsequently validated at the shop after break-in, then there isn't any reason one would need to do the propping exercise as long as your achieving 6000-6200 rpms and maintaining water pressure?

Mike what is the your water pressure at 6200 rpms and what is the minn. water pressure do you know?

[mikesxpress]

Mike what is the your water pressure at 6200 rpms and what is the minn. water pressure do you know?

Ron the water pressure at WOT is based on the boat/rigging but mine runs 25+.