question about trim/taking off...

hello everyone.. i recently got a 17' 1988 checkmate w/ 150 merc xr4 ....
ok so its my first boat...i need to ask about the trim up/down stuff...
ok so i know to trim it down a little and start it up, so that the props underwater of course...but...should i trim it ALL the way down so that its hugged up against the boat for when im done warming it up and ready to starting going out putting it into gear? i trim it down to where it gets to those prongs and then it goes slower and pushes those2 rods in ...i know its normal bit i felt like i was going to break something after it started going slower pusing on those prongs but a guy said i need to start out with it all the way trimmed down..or in i would call it...and then once i get going all i have to worry about is trimming "up".....so, any info helps....the way i was doing it was i think the motor was barley touching the prongs as i started out and actually when i gave it throttle...it bogged out, or like seemed like it was dying out and even shut off on me one time....then i messed with the trim not really knowing what i was doing and at certain points it would just start taking off normal as i throttled it....i dunno..it was confusing...seems like everyone else just knew about their stuff so i guesss it just takes time....i had it up to 45 and it felt like i was flyin... but anyway, the prop says 12x28 on it...is this a ski prop? or speed? i just dont know the differences i just know they have different "pitch's" or somethin like that rite.....anyway.... thank you all...

Re: question about trim/taking off...

Welcome to iboats!

As a fairly new boat owner, I have learned a lot, and much of that info has come from here. So the best advice I can give back to you is do searches at this forum. There are a lot of posts that address your questions. And many posts that will adress questions you will come up with .

As for trim adjustments, you will get the feel for what works best on your boat as I did, but in general keep the trim down when taking off, and adjust up slightly after on plane.

That prop seems like a high pitch, but it sure could be right for your boat/motor combo. What were the RPMS at 45? 45 is not fast at all for that boat/motor combo, so I would hope you weren't at WOT (wide open throttle) at that speed.

best to search here and experiment with your setup.

Have fun, get crazy, and stay safe!

BTW...post up some pics!

Re: question about trim/taking off...

With the right prop your boat should be going in the 60s (assuming the foam isn't waterlogged).

Look up the forums at checkmte-boats.com, more than likely someone there has the exact same boat as you and can answer any questions. Yes, A 28 pitch prop seems like a bit much. You didn't mention whether or not there's a jack plate.

As far as trimming, some of it you just gotta' play with and gain experience. Normally you'd trim most of the way down to start, and start easing the trim up as the boat comes on plane. Then it's a matter of experience to know how much to trim up. In general if you go too high on trim the boat will start to bounce, or porpoise, then you need to trim in just a bit. You've got to think ahead when you turn, trim down a bit as you enter the turn, then trim back up as you come out of the turn. Just take it easy with the speed 'till you get the feel for that boat.

BTW, I'm just finishing up a total rebuild on a '79 Checkmate Eluder (18-1/2 ft bow rider) with a '90 Johnson 200, hope to get her wet in the next couple of weeks.

Re: question about trim/taking off...

I start off with trim all the way down. Once on plane, I begin trimming up. Starting off with trim down keeps bow down and shortens "hole shot" (time to get on plane). My previous boat would porpoise (bow bounce up/down) if I trimmed to high while on plane. With current boat I can hear the prop start to slip if I trim to high before it starts to porpoise. As you trim up while running, you can should feel a slight speed increase for same throttle position.

Also, if the water is choppy/rough the ride is much better if I trim down. This lowers the bow and lets the deeper V of the bow slice through the waves.

As said, with experience on your boat you will learn the best trim settings for different situations.