V8 Full Throttle

[fuelleak]

Serial # 2B571507. 2019 250 Pro XS. Dropped my boat off at a Merc dealer to see if Hotfoot was opening throttle all the way. They called to say sensor was showing that it was opening 91%. They called Merc to double check to see if that was in spec and haven't heard back. Don or anyone have any idea on this? The dealer seems to believe that 90 tp 100% is with in spec. I just cant get this motor to turn over 5800 rpm. I have been running a 24 4 blade Fury but tried a 23 3 blade Fury off a friends boat and got the same 5800 rpm. My 24 hole shots just fine even with a load and no matter where I run on my Atlas and how I trim it, it seems like its stuck at 5800??

[jphillips2546]

Should be 100%. Mine was 88 and they had to adjust the hotfoot. Easy to do.

[fuelleak]

This dealer is saying its "not" easy to do. Where is the adjustment made? At the Hotfoot?

[jphillips2546]

It took about 2-3min but was done at the hotfoot. Your setup could be different. Mine was a new Phoenix 920 with a 250R (Previously 250 2s so it was effectively a re-power)

[fuelleak]

Interesting, hope this dealer gets it to 100% because I know something is a bit off.

[jphillips2546]

It looks like you can do it yourself. I think its an easy adjustment.

[21xTriton05]

Back the bolt out on the pedal so you can pull the foot pedal further back towards you then adjust the engine side. The engine SHOULD read 100% or you wont get 100%

[mikesxpress]

Gary do you have an advanced (level 1) Merc monitor? Once reset it will show your max rpms.

Can you raise the plate and trim getting the engine to turn more than 5800 rpms (causing slip)? *Trying to eliminate an issue not related to the throttle.

Rob is correct. The dealer has to get the Hotfoot set to 100% or it's not going to get full throttle. We had to remove my Hotfoot return stop bolt to gain the full range of motion in order to get 100%. This is not an issue as long as your return spring is strong enough to pull the pedal all the way back.

You can't do this yourself as the computer must be attached to see the actual range the DTS says it's at.

[EuropeanAM]

Adjustment is done at the hotfoot AND throttle cables. IDLE position is the starting point- and it's important that the idle stop screw be set back with adequate spring tension to return consisitently.

If the idle stop screw were, for instance, 1/2" too far out, it would move the whole range of the hotfoot closer to the floor (in some cases this may result in the hotfoot bottoming out against another surface before 100% throttle is reached).

Correct position, at WOT, is indeed 100%.

[FISHBONES]

Thanks Mr EuropeanAM after months of guessing i think my boat needs DTS adjustment something the dealer or manufacture should of perform before delivery. Also what is pcm the update for?

[EuropeanAM]

Also what is pcm the update for?

No idea what you are asking here... ?

[FISHBONES]

Just asking what is in the update for the new V8 250?i was at the shop when they download a update to computer. just wonder what it was for? sorry about the bad grammar.

[EuropeanAM]

You would need to ask the person that was operating the computer at that time. May have simply been a Computer Diagnostic System Update (although there are sometimes reflash versions or updates, depending on your engine serial number and the calibration version that was in the engine at the moment).

Information on either was available to the person operating the computer (specifically).

[Sam378]

I just brought my boat to the dealer today with same issue, 2019 Phoenix with the new 250 fourstroke, I tried a 24p fury and a 25p fury and the rpms on the 24 was 5600 at 70 mph and the rpms on the 25 was 5700 at 74 mph, only thing I could think of was it’s not hitting 100% throttle

[EuropeanAM]

I just brought my boat to the dealer today with same issue, 2019 Phoenix with the new 250 fourstroke, I tried a 24p fury and a 25p fury and the rpms on the 24 was 5600 at 70 mph and the rpms on the 25 was 5700 at 74 mph, only thing I could think of was it’s not hitting 100% throttle

Good idea to open a separate thread for your separate boat/motor (see Forum Announcements for details).

Also wondering if you might have some of the numbers reversed there (certainly doesn't add up, although if either prop is used or has even the SLIGHTEST damage, that could account for it).

[JThomas]

http://www.bbcboards.net/showthread.php?t=926397

[EuropeanAM]

To again stress the importance of the Hotfoot IDLE STOP:

Hotfoot IDLE STOP is extremely critical on these engines- far more than previous 2-stroke models as the stop on the HOTFOOT at idle is the primary point from which all throttle settings will run.

If that throttle linkage doesn't come back to the same point each time... it will be incorrect when it adapts the next time (at keyup or startup).

[bigpat07]

Any update?

[241]

I've had mine reset now twice and it's again back to not getting full throttle. Anyway know how to resolve this issue? I have the updated hot foot, enough spring to make my leg hurt on long runs. What else?

[mikesxpress]

Use a different shop. We set mine on a 2009 Hotfoot in July 2018 and it's still set over 2 years later.