225 Mercury Optimax WOT question

[MattVT18]

I just bought a boat with a 2006 225 Mercury Optimax (cowl says Pro XS but it has a brand new power head so not sure the difference) SN 1B389342. It has a 25P Tempest prop. I took the boat to the lake to get started on the break in Friday. With the trim all the way down I was only able to get ~4400 RPMs. I bumped the trim up just a bit and obviously the RPMs went up but my trim gauge was acting up so I didn't go very high. I raised the jackplate about an inch throughout the day to see if I could get any closer to the ~5k RPMs recommended for the break-in but didn't really see much change. I have the MercMonitor ECO gauge, so all temps, RPM and such were not read from analog gauges. I would have thought raising the motor would have increased the RPMs even with it tucked under, was that incorrect? How can I check that I'm really getting WOT or close to it? I have a service manual (90-8M0057453) for my last motor, a 2015 175 Pro XS that has a procedure for setting WOT but the illustration is different than what I see on my motor. If the procedure is the same I can probably figure it out. I'd just like to confirm the hot foot, cables and linkages are set right. The 4400 was at WOT (very short bursts). I messed around from ~3K to ~4200 for nearly an hour riding around and moving the JP and the break in timer on the MercMonitor reflected that time in the break in countdown timer. I just want to make sure I'm breaking this thing in right. The dealer didn't seem concerned with the RPMs as long as I was varying the throttle around and plowing water...I was doing both.

[tomloans]

First thing I would do is get a friend and step on the hotfoot and see if the throttle is open all the way. It should be 90 degrees open.

[tomloans]

Was the powerhead fully dressed or did they use the prior dressing from the old powerhead?

[MattVT18]

I'll check the throttle blade position to see where it's at. I should have some time later this week to mess with it some more. I'm not sure if it was a fully dressed powerhead or not, I didn't ask. FWIW it starts and runs fine. The dealer put about 20 minutes on it before I picked it up. The last time I had a boat with a new powerhead I had to make some small adjustments once it was broken in to get it just right. I might go ahead and pick up a service manual for this engine as well, they are very helpful in getting things dialed in.

[JOE54]

manual will have all info you need for your mtr and adjustments

[EuropeanAM]

First thing I would do is get a friend and step on the hotfoot and see if the throttle is open all the way. It should be 90 degrees open.

Not quite correct. Take a look at the FAQ Section, near the bottom of the page there is a "Hotfoot Adjustment" post.

That post will accurately explain how to check that you are achieving WOT position.

Note: Your engine will not be able to reach peak RPM's until you RAISE THE TRIM TO AN APPROPRIATE LEVEL. See also the FAQ Section for Optimax Engine Break-In Instructions.

[MattVT18]

Thanks for the replies. Don - the break-in procedure provided by the dealer was pretty much the same as what is posted here. I'll read through the hot foot setting thread as well. I've got a new trim sensor on the way so I can get a better feel of where I'm at while running around. Hopefully it'll be here Thursday but if not I'll just set the motor to slightly below level trim before I take off and leave it there while I run around some more. The dealer recommended leaving it tucked or at least slightly below level for the first couple of hours.

[JOE54]

trim engine to a position where steering has no adverse effects on boat handling at breakin

[MattVT18]

JOE54 - not sure I follow what you're saying...

[EuropeanAM]

Raise trim enough to prevent the hull from "plowing water", but no more than level trim (for the 1st two hours). Reasonably well explained in the FAQ post.

[MattVT18]

I thought that might be what he meant, just wanted to clarify.