How Much Trim Is To Much Trim???

[thedukeryan]

How high can you safely trim a i/o up out of the water without doing any damage. I am curious about different situations such as wide open cruising vs. shallow water idling etc. If it helps mine is a Bravo 3 but I am curious about all i/o in general.

 

[nuboat2me]

Re: How Much Trim Is To Much Trim???

How HI I trim???

Just enuff to stop porposing...

I rarily if EVER run at WOT so I trim up until she seems just right. My boat planes is seconds. I'd say, I am running at 60-75% throttle... I try to keep that last 4 - 5 ft of boat in the water... I cruise more than anything else... I don't pull tubers or skiers...

I would think trimming PAST porposing, you start cavatating... and then RPMS climb...

Just my $.02...

Happy Boating!!

 

[Philster]

Re: How Much Trim Is To Much Trim???

It depends on how much control you need. At 60 MPH + and on the edge of porpoising, one man's 'control' is another man's 'dangerous'.

 

[tcgobucks]

Re: How Much Trim Is To Much Trim???

It depends on how much control you need. At 60 MPH + and on the edge of porpoising, one man's 'control' is another man's 'dangerous'.

...but one man's "dangerous" may be another man's "just starting to get fun"....

 

[thedukeryan]

Re: How Much Trim Is To Much Trim???

Im looking at more of the mechanical side of things I guess. I know if I where to cruise around with the trim all the way up it would probably trash my drive in a short period. I guess Im curious about how high the drives are designed to go without excess wear on the parts? I like playing around with the trim to find the most efficient speed/ride. I just don't wanna go to high and find out its gonna wear out my drive.

 

[clockwatcher]

Re: How Much Trim Is To Much Trim???

I think if you stay within your gages range you should be fine. Past that you wear on the u-joint and gimbal bearing with power beyond idle.

 

[thedukeryan]

Re: How Much Trim Is To Much Trim???

Hmmm... My trim gauge doesn't have a red line or anything like that or at least none that I can remember. My old boat would stop trimming at a certain point and then you used the trailer button to bring it up all the way. My Rinker does not have this and will trim all the way up if I want it to. Anyone know a general standard? Say 1/4 or less, 1/2 or less, 3/4 or less? I usually feel fine at around 1/4 anything over than that gets me a little nervous. My buddy says he trims 1/2 all the time and neve had any issues but he isnt exactly a go to guy.

 

[Brewman61]

Re: How Much Trim Is To Much Trim???

Enough so that you'e not porposing, you have control of the boat, and your water intake isn't impacted. In really shallow or rocky waters, I'll trim up pretty high, but go pretty slow too. No wake speeds.

 

[Alpheus]

Re: How Much Trim Is To Much Trim???

My trim gauge doesn't have a red line or anything like that or at least none that I can remember.

No but your Outdrive is equipped with a trim limit switch. If it is adjusted correctly and in working order, your parts will be fine at wherever you choose to run it. But if your limit switch is not working or out of adjustment and you put the drive up to high at WOT, you will know it in a hurry...

 

[a70eliminator]

Re: How Much Trim Is To Much Trim???

While out of the water I've observed the angle of the drive when trim gauge reads full out, in the water on plane I cannot trim to full out before the prop blows out, I guess what I'm trying to say is that your prop will probably blow out before the angle overwhelms the universal joint.

 

[JimS123]

Re: How Much Trim Is To Much Trim???

Operating at "running" speeds you should be able to max out the "trim" as high as it will go without doing any damage to the outdrive. Now, the boat may porpoise badly and you may experience control problems, but no damage should result, per se'

My Mercruiser Owners Manual says that when running above the trim range (i.e., using the trailer button) the rpms should be kept below 1000.

I "calibrated" my trim gauge so that I know where the outdrive is positioned. When I'm in the "3/4" up position my skeg is just above the bottom of the boat. I run in shallow water frequently to get to a secluded beach and have never had a problem with the drive (nor ever hit the bottom either).

The bottom line is keep the rpms low and you should have no problem.

 

[thedukeryan]

Re: How Much Trim Is To Much Trim???

Hmmm... So does it automatically stop trimming at a certain point when in motion? My current Rinker does not have a trailer button to bring it up out of the water, when trailering I just hold the trim until all the way up. My previous boats all had trailer buttons. It will come up half way while cruising I know that but never wanted to just hold it up and wait until it stops due to fear that it will come all the way up if I let it.