2019 521L Pro XS 4S only 5200 RPM?

[B. Dillon]

Pro XS with a 23p Fury. No alarms Thinking it's the plug in the prop. How many plugs are you guys leaving in?

[mactlman]

prop plugs don't affect anything but take off rpm's

[Rip Bass]

True,check to see if you are getting full throttle.

[Biersmith]

And full trim?

[jc2bg]

I know there have been several cases of hot foot out of adjustment on the 4S Mercuries, if a hot foot is involved here.

[B. Dillon]

Hot foot adjustment. Thanks!

[mikesxpress]

Lot's of dealers are not familiar with these V8's & don't get the demand/demand linear (idle to WOT) set correctly with the hotfoot and laptop/setup software. This same software also sets your tilt/trim range. Once all that has been set you should see close to 5800 rpms. That is NOT good enough. Getting the prop "true pitched" should put you at the 6200 rpm goal where this engine is designed to run at. Don't let the prop butcher do anything else to it but pitch it true. Plug all the holes on the PVS. The PVS system does nothing for the V8.

[dbw1968]

Lot's of dealers are not familiar with these V8's & don't get the demand/demand linear (idle to WOT) set correctly with the hotfoot and laptop/setup software. This same software also sets your tilt/trim range. Once all that has been set you should see close to 5800 rpms. That is NOT good enough. Getting the prop "true pitched" should put you at the 6200 rpm goal where this engine is designed to run at. Don't let the prop butcher do anything else to it but pitch it true. Plug all the holes on the PVS. The PVS system does nothing for the V8.

My dealer told me they couldn't adjust my hotfoot anymore. I was only able to get 94% throttle on my 2020 175 pro xs. I had to hook up my throttle cable to my hand control. Are u telling me they could have set it with the computer to demand linear and not made me buy another cable?

[mikesxpress]

Some hotfoot's required that the throttle stop bolt to be removed to get the demand/demand linear range. Mine did not. We backed it all the way off and that was satisfactory. While there is always a 1st for everything, I've not heard of anyone with an existing hotfoot top load that couldn't get it set correctly.

[B. Dillon]

I removed the throttle stop bolt entirely. Got 200 more RPMs to 5400. It's definitely something with the hot foot installation. Damn shame.

[dbw1968]

I called mercury and told them I had a TH marine hotfoot and they told me that my Year hotfoot would not get over 95% throttle. They told me the new TH marine hotfoot go to 100%. Just for info for anyone with an older HF.

[mikesxpress]

I have a 2009 Hotfoot hooked to my V8.

[RGK456]

I called mercury and told them I had a TH marine hotfoot and they told me that my Year hotfoot would not get over 95% throttle. They told me the new TH marine hotfoot go to 100%. Just for info for anyone with an older HF.

And what year model is your?

[dbw1968]

I bought the boat 3 years ago but don't know the year of hotfoot. I just know it's not a newer one.

[B. Dillon]

Lot's of dealers are not familiar with these V8's & don't get the demand/demand linear (idle to WOT) set correctly with the hotfoot and laptop/setup software. This same software also sets your tilt/trim range. Once all that has been set you should see close to 5800 rpms. That is NOT good enough. Getting the prop "true pitched" should put you at the 6200 rpm goal where this engine is designed to run at. Don't let the prop butcher do anything else to it but pitch it true. Plug all the holes on the PVS. The PVS system does nothing for the V8.

This was spot on with what I was told tody.

[RGK456]

This was spot on with what I was told tody.

sent you a PM question

[RGK456]

I have a 2019 Z520L with 250 XS 4S, I sent Mercury Marine the question online around the TH Marine Hot Foot and the reply was:

Good Morning,
Thank you for your e-mail regarding your Mercury engine, serial #XXXXXX. We appreciate the opportunity to respond to your concerns.
This engine was manufactured in October of 2018 and was part of the first year these engines were offered. We did find that in 2018 some TH Marine Hot Foot models that were top-load did not have enough travel in them to reach 100% demand linear in the engine. As far as we know TH Marine has either come out with another design or they may even possibly have a kit that retrofits onto your current hot foot. The only way to know for sure that we are actually reaching 100% demand linear is with a Mercury Marine dealer diagnostic tool called G3 which every authorized Mercury Marine dealer should have.
We hope this information is helpful to you. Should you have any further questions or concerns, please contact our Customer Service department at 920-929-5040 between the hours of 7:30 am and 4:30 pm, Monday through Friday, CST.
Sincerely,
Mercury Outboard Customer Assistance

And TH Marines Website states "Now compatible with all Mercury 175-300 Pro XS outboard motors"


https://thmarinesupplies.com/product...-foot-throttle

Looks maybe we need a newer model of hot foot possibly. I know mine does not look like this one.............

From TH Marine:

Thank you for contacting T-H Marine,


It could be the previous style top load Hot Foot that does not have the cut out in the side plate to allow for full throttle. We made that modification about a year or so ago and we know it works. If you have a top load Hot Foot that has the cut out in the side plate but is still not getting full throttle then it would either need adjusting on the motor end or the throttle stop bolt behind the pedal needs adjusting.


This Hot Foot states not compatible with new Pro XS 4S: https://thmarinesupplies.com/product...-foot-throttle

Hopefully this will help others with similar questions and problems. I am planning on having my dealer check my WOT in a few weeks when I take it in for service. I have never seen anything greater than 5800 or so yet with light load, GPS 70 or so. It ran a little better before I move the HF up on the slide, thinking that might have messed with something.

[Nitro88]

I have a 2019 Z520L with 250 XS 4S, I sent Mercury Marine the question online around the TH Marine Hot Foot and the reply was:

Good Morning,
Thank you for your e-mail regarding your Mercury engine, serial #XXXXXX. We appreciate the opportunity to respond to your concerns.
This engine was manufactured in October of 2018 and was part of the first year these engines were offered. We did find that in 2018 some TH Marine Hot Foot models that were top-load did not have enough travel in them to reach 100% demand linear in the engine. As far as we know TH Marine has either come out with another design or they may even possibly have a kit that retrofits onto your current hot foot. The only way to know for sure that we are actually reaching 100% demand linear is with a Mercury Marine dealer diagnostic tool called G3 which every authorized Mercury Marine dealer should have.
We hope this information is helpful to you. Should you have any further questions or concerns, please contact our Customer Service department at 920-929-5040 between the hours of 7:30 am and 4:30 pm, Monday through Friday, CST.
Sincerely,
Mercury Outboard Customer Assistance

And TH Marines Website states "Now compatible with all Mercury 175-300 Pro XS outboard motors"


https://thmarinesupplies.com/product...-foot-throttle

Looks maybe we need a newer model of hot foot possibly. I know mine does not look like this one.............

From TH Marine:

Thank you for contacting T-H Marine,


It could be the previous style top load Hot Foot that does not have the cut out in the side plate to allow for full throttle. We made that modification about a year or so ago and we know it works. If you have a top load Hot Foot that has the cut out in the side plate but is still not getting full throttle then it would either need adjusting on the motor end or the throttle stop bolt behind the pedal needs adjusting.


This Hot Foot states not compatible with new Pro XS 4S: https://thmarinesupplies.com/product...-foot-throttle

Hopefully this will help others with similar questions and problems. I am planning on having my dealer check my WOT in a few weeks when I take it in for service. I have never seen anything greater than 5800 or so yet with light load, GPS 70 or so. It ran a little better before I move the HF up on the slide, thinking that might have messed with something.

Great info, thanks for sharing. I didn't seem to have much of a problem with the speed until i did some other wiring and and needed to unscrew the hotfoot. That is when the slowness started and never hits WOT.