tilt/trim mercury 115 question

relics hunter

Petty Officer 2nd Class
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Jun 11, 2010
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118
We have our first boat (used). It is a 15' bowrider with a 115 1975 mercury on it. There is no TNT on it and it's quite a heavy motor. It there a recommended way to raise and lower it? Other then a really expensive after market TNT?
 

RRitt

Captain
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Mar 30, 2006
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3,319
Re: tilt/trim mercury 115 question

power tilt is fairly inexpensive. You can rig something up using a generic $50 hydraulic actuator. Trim is the hard part. Because you need either a big bore or multiple cylinders trim is much more expensive than tilt.
 

Wingedwheel

Lieutenant Junior Grade
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Jun 16, 2009
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1,071
Re: tilt/trim mercury 115 question

There is an assist lever that is made for exactly what you need.
 

relics hunter

Petty Officer 2nd Class
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Re: tilt/trim mercury 115 question

The tilt for getting it on and off the trailer is needed for sure. The trim would be great but unless I lucked out on a used one...
Next question can the tilt be used when say you need to raise it when coasting into shallow water. Just cut the engine and tilt it up and coast. Or do you need to be at rest first?

I looked at the handles to raise it and they all seemed to be for smaller engines. I have not seen any rated for above a 70 hp. A 115 is rated at weighing 347lb. I can't see pulling it from the top lid.
 

75TowerOfPower

Petty Officer 1st Class
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Apr 17, 2009
Messages
331
Re: tilt/trim mercury 115 question

Either the assist cylinders or rigging up a system to raise and lower it.

The 115 has a handle built into the top cowl that you can attempt to lift the heavy chunk with.
 

RRitt

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Joined
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3,319
Re: tilt/trim mercury 115 question

The tilt for getting it on and off the trailer is needed for sure. The trim would be great but unless I lucked out on a used one...
Next question can the tilt be used when say you need to raise it when coasting into shallow water. Just cut the engine and tilt it up and coast. Or do you need to be at rest first?

I looked at the handles to raise it and they all seemed to be for smaller engines. I have not seen any rated for above a 70 hp. A 115 is rated at weighing 347lb. I can't see pulling it from the top lid.

most tilts will actually trim up to about 10HP. then the engine is too strong for them and pushes open the safety valves.

The big task is figuring out an upper and lower pivot pivot point. Tilt is really same thing as a floor jack except that it goes in both directions and has an electric motor. Up under the swivel bracket you should find two un-used holes. That is where a rod goes across for top end of tilt cyclinder. Now you have to find the bottom mounting and measure the desired length of ram. A generic waterproof trim pump with four ports is about $200 new. Once you get your dimensions then you can hunt down a mercury, evinrude, omc, or force of right size ... about $30-$50. High pressure tubing will cost about $2 per foot.

If it was me ... I would wait until off-season and get the original mercury full trim & tilt for cheap off amazon or cgaigs-list.
 

gregtobin

Petty Officer 3rd Class
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Sep 18, 2006
Messages
99
Re: tilt/trim mercury 115 question

I have a similar set-up with a 17 foot bowrider and a 1975 Merc 115 straight six.
I looked into rigging up a trim system and bought various parts from ebay and none of them really worked as advertised. Be careful not to waste your time and money on this. I'd suggest new parts or forgo the trim.

For now (and the past 4 years), I have manually trimmed the motor when approaching the shallows with the motor off. It would be great to have power trim to adjust the angle
One thing to be very careful about. A previous owner removed the reverse lock system that prevents the motor from tilting when shifting into reverse. If you shift to reverse and apply too much power, the motor can flip into the boat, break loose, etc. Make sure that this safety system is in place. If it isn't, don't let anyone other than you operate the boat unless they can be trusted to be very gentle in reverse.

Greg
 

relics hunter

Petty Officer 2nd Class
Joined
Jun 11, 2010
Messages
118
Re: tilt/trim mercury 115 question

This all a lot of great information. I'm going to go out a few times and see how much it effects activity's to not have a TNT. Maybe just a tilt pump, maybe just a lever. It does look like the lid is strongly attached to the body. I don't think I'll go the full TNT way unless one fall in my lap. Look after season.

Thank you for the safety tip about the reverse lock. I am thinking you mean the reverse lock horn that grabs the bar? That looks in tact. If that is not the right part, please tell me.

Thanks
 
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