2006 2120 SC F225 Motor Mounting Hight.

[shawnee83]

I'm hoping DaleH reads this one as he seems to be knowledgeable on this subject. Per DaleH's previous advise, I finally had someone with me who I could trust to drive long enough to check where the AV plate was riding while at speed and full trim per speed/power. Anyway, here is the results. 4200 RPM 28.5 mph GPS salt water. Motor is mounted 1 hole down from the top hole. If I understood DaleH's info correctly, it appears that my motor is mounted to low. I couldn't see any of the AV as can be see in the attached photo. Any advise as to which hole I should try first when I move it would be welcome.

 

[DaleH]

I'd go up at least 1 hole, but keep in mind this is really a 'try it and see' exercise. Note you will find you need to trim in when turning, if you haven't already. If/when too high, the prop will suck air/cavitate whilst on plane even in slight sea states, like a following sea.

But the "right" height setting can really improve rig performance! Note it is boat, setup (gear, load, etc.) and prop specific to EACH boat ... long way of saying 'no one size/setting fits all' ...

 

[shawnee83]

Thanks DaleH. I'll move it 1 hole up first and post results. By the way, forgot to mention I had a little less than 1/2 tank of fuel 2 adults 1 child and a cooler for the day. Not a very heavy load. Thanks again!

 

[rloomis]

My 2120 SC has a F225 too and I raised the motor twice, finally ending up at the highest bolt hole position.
What prop do you have? I'm spinning a Yamaha SWS II 15.75 x 15pitch and can just touch 40Mph@5900RPM.
You can see in the picture I also added a Bob's Machine Shop wedge to give a little extra negative trim.
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[Megabyte]

My 2120 SC has a F225 too and I raised the motor twice, finally ending up at the highest bolt hole position.

Shawnee... after seeing your in-water photo, and the photo of where you are now, I agree with rloomas.
I think you will eventually end up in the last hole, but as Dale said... "try it and see".

 

[DaleH]

FYI, I have a set if those trim wedges if anyone needs or wars to try them out.

 

[shawnee83]

I'm thinking that I'm going to end up at the highest hole too. Rloomas, I'm ashamed to say that I keep forgetting to note the prop size/specs on my current prop. I do know for sure that it is the stock prop that came with the boat on this 2006 engine. I have also verified that the serial number is a 2006. I'll check the prop next time I get to my boat. Couple of weeks? My top speed has been about 44mph at 6000 RMP. Has that wedge helped achieve a lower planing speed? Where you trying to correct porpoising?

 

[Sully]

Im at the top hole myself
Have too ....! IMO