Increasing MC-1 trim range

[Don S]

Re: Increasing MC-1 trim range

If you just push in on one cylinder, and it is out any, it will just push the other cylinder out.

 

[ziggy]

Re: Increasing MC-1 trim range

went out and push on the port one. no movement. i think it's all the way in.

ya can see the line on the shaft of where full in is.

this is the one i measured. i think it's full in.

 

[Cresco750]

Re: Increasing MC-1 trim range

Thanks for that zingy. I didn't get a chance to measure mine after work last night; I'll see if I can squeeze it in tonight.

Cheers

 

[Cresco750]

Re: Increasing MC-1 trim range

Right-oh, just measured the distance between mounting centers and it comes in at exactly 19 inches with rams installed, and 18 7/8 inches when rams removed and out drive positively bottoming at its stop.

Sooo, I guess that suggests that my drive is trimming all the way down and that's just the way it is?

Sorry Bubba, I was meaning to note the number of he rams but completely forgot.

Thanks everyone for all your help and suggestions on ths one. Cheers.

 

[Don S]

Re: Increasing MC-1 trim range

I would still bet the transom is not angled as much as it should be. Impossible to tell from the picture.

 

[achris]

Re: Increasing MC-1 trim range

I would still bet the transom is not angled as much as it should be. Impossible to tell from the picture.

The photo looked pretty square to me, so I put a protractor on my screen. It showed the transom angle at 12?... I suspect something else is going on here...

 

[Cresco750]

Re: Increasing MC-1 trim range

I tried to take the photo as square on as I could so as to give a reasonably accurate idea of the actual angle. I'm at a bit of a loss as to what else could influence it if the dive is hitting the stop on the transom ring ( I am just assuming thats where it contacts?)
Don, perhaps the transome could or should have more angle, but from an untrained eye it doesn't appear to be significantly less than other boats in the park. Not much can be done if that is the issue I guess? Not like you can add wedges like on an outboard?

 

[haulnazz15]

Re: Increasing MC-1 trim range

Not that this solves an issue of improper transom angle or trim pistons not fully retracting, but why do you need more "in" trim? Seem like that drive angle should still be effective for trim, and once on place you'd likely trim it up further anyhow? Maybe I missed it earlier, but I just don't understand what the reasoning is. I would think that you would be plowing/bow steering pretty hard if you were on plane even with that trim level.

Also may be redundant, but have you tried just bleeding the system? If nothing else, it might allow you to ensure that the trim is fully retracted if the system is depressurized.

 

[Don S]

Re: Increasing MC-1 trim range

It helps to get the bow down before you get on plane. That time when you first give it throttle and the bow points to the sky. On heavier boats, it makes that transition from pointing to the sky to leveling out quicker.

 

[haulnazz15]

Re: Increasing MC-1 trim range

I realize that Don, but the angle in the pic made it look like there wouldn't be much difference in the angle even if he got another inch of "in" trim. It didn't appear that it was causing much trouble in planing, which is why I asked what the investigation was for. If he was having trouble planing, then I'd understand.

 

[Don S]

Re: Increasing MC-1 trim range

In the first sentence of his original post he stated he was looking for more nose down force.

 

[Cresco750]

Re: Increasing MC-1 trim range

Not that this solves an issue of improper transom angle or trim pistons not fully retracting, but why do you need more "in" trim? Seem like that drive angle should still be effective for trim, and once on place you'd likely trim it up further anyhow? Maybe I missed it earlier, but I just don't understand what the reasoning is. I would think that you would be plowing/bow steering pretty hard if you were on plane even with that trim level.

Also may be redundant, but have you tried just bleeding the system? If nothing else, it might allow you to ensure that the trim is fully retracted if the system is depressurized.

Currently, I find that the hull rides best when the drive s trimmed right in, unless the water is dead flat,then I can trim out just a little. In a rougher sea I am relying too much on the trim tabs to get the nose down to reduce pounding and improve ride. If the drive could be trimmed in just a little more then I feel I would get better rough water handling. Time onto plane would also improve, but that's not my motivating factor.

 

[Bondo]

Re: Increasing MC-1 trim range

Currently, I find that the hull rides best when the drive s trimmed right in, unless the water is dead flat,then I can trim out just a little. In a rougher sea I am relying too much on the trim tabs to get the nose down to reduce pounding and improve ride. If the drive could be trimmed in just a little more then I feel I would get better rough water handling. Time onto plane would also improve, but that's not my motivating factor.

Ayuh,... Put a straight edge along the keel line of the hull, say the last 6' or 8' of it, 'n see how true it is....

It could very well have a huge rocker in it....

Last fall, I stopped by a fellow iboater's up in Maine, 'n he had been whinin' 'bout the exact opposite of yer problem,...
Severe nose plowin',... poor handlin', 'n no speed...
After checkin' out all the more obvious things, 'n many posts from 'im, that everything was perfect, but it still nose plowed,...
I grabbed a 6' bar, 'n held it to the keel line,...
There was a 2" hog in the bottom, 'bout from a 1' up, to 'bout 3' up the keel line...

Donno if he's gonna fill/ fix it or not, ain't heard anything in awhile...

 

[Cresco750]

Re: Increasing MC-1 trim range

Hmm, not really an easy fix for the fellow?!

I'm now wondering whether my quest for more nose down force could be assisted by fitting one of the many cavitation plate hydrofoils, such as our locally made "Permatrim"? Since my drive does have a certain amount of "in" trim the Permatrim would also increase the amount of hydro-dynamic deflection - basically acting as a single trim tab selected to "bow down".

 

[achris]

Re: Increasing MC-1 trim range

Hmm, not really an easy fix for the fellow?!

I'm now wondering whether my quest for more nose down force could be assisted by fitting one of the many cavitation plate hydrofoils, such as our locally made "Permatrim"? Since my drive does have a certain amount of "in" trim the Permatrim would also increase the amount of hydro-dynamic deflection - basically acting as a single trim tab selected to "bow down".

Unless the installation is at least 1" above the normal height, adding a 'wing' on the drive will cause more problems than it will solve.

I will be working near you in Feb/March. If I get the opportunity, would you like me to come and take a look?

Chris.....

 

[Bondo]

Re: Increasing MC-1 trim range

Hmm, not really an easy fix for the fellow?!

I'm now wondering whether my quest for more nose down force could be assisted by fitting one of the many cavitation plate hydrofoils, such as our locally made "Permatrim"? Since my drive does have a certain amount of "in" trim the Permatrim would also increase the amount of hydro-dynamic deflection - basically acting as a single trim tab selected to "bow down".

Nope,.. No it's not,... Actually, it just pointed out how Bad the stringers are....

Point is,... Until you Check yer's, We're all just shootin' into the wind....

I agree with Chris, a hydro-foil is a pizz poor band-aid that causes as many problems as it fixes...

 

[Cresco750]

Re: Increasing MC-1 trim range

Unless the installation is at least 1" above the normal height, adding a 'wing' on the drive will cause more problems than it will solve.

I will be working near you in Feb/March. If I get the opportunity, would you like me to come and take a look?

Chris.....

Hi Chris
That would great. My boat's in Pine Harbour, Auckland. Drop me a line closer to the time.

Cheers, Neil

 

[kilowatts]

Re: Increasing MC-1 trim range

Hi Guys:

I think I know why the rams are installed as they are in the first picture because mine are installed the same way! I purchased a set of aftermarket rams from SEI as they were cheaper than repairing the old ones. They came with the stainless connections as shown in the photograph and like the photograph can only be installed upside down on the MCM 1 drive. I don't know whether this would have any effect on the trim as mine works fine with the same method of installation.

kilowatts

 

[achris]

Re: Increasing MC-1 trim range

View attachment 176718

Hi Guys:

I think I know why the rams are installed as they are in the first picture because mine are installed the same way! I purchased a set of aftermarket rams from SEI as they were cheaper than repairing the old ones. They came with the stainless connections as shown in the photograph and like the photograph can only be installed upside down on the MCM 1 drive. I don't know whether this would have any effect on the trim as mine works fine with the same method of installation.

kilowatts

The rams are installed correctly, with the external return line on the underside of the ram. Even so, the travel of the ram would be the same regardless of which way up it's installed.

Chris........

 

[kilowatts]

Re: Increasing MC-1 trim range

Hi Guys:

My apologies Chris, but my understanding was the external return line should be installed on the top of the cylinder to avoid collision with floating objects but as you know, the original rams had the connection all at the same end so the aftermarket connecter has to be installed upside down. I may be wrong though!

kilowatts