Adding CMC PT-35 Power Tilt & Trim to my Lowe 1448T

I had originally thought about adding power tilt/trim to easily lift my motor on demand. After taking the boat out on a really shallow lake (max dept 4′, average depth seemed close to the dept of my prop!) I was pushed further to want this feature, so I went out and got it.

The unit I purchased is the CMC PT-35 Power Tilt & Trim, and it is gorgeous. Designed for motors of 35HP or less, it is made from machined aluminum and is not only sturdy and functional, but beautiful to look at as well. I slid my motor over on the transom, found the center line, and after lots of calculations, decided on the mounting height.

The unit moves your motor back another 5″ or so, which makes mounting the motor higher desirable since the water that comes under the boat will begin to rise after clearing the transom. They suggest mounting the motor 1″ to 3″ higher in relation to the transom than it was before. After doing all the math and looking at my layout, I mounted the top of the transom side of the unit level with the top of the transom itself. This put me at the minimum 1″ higher mark as a starting point, and I figured I could always raise the motor up on the mounting plate if I needed to.

After measuring everything about five times, and marking the bolt holes onto the transom, I finally did the deed, drilling holes into the transom of my new boat. Once done, I test fit it with the bolts and thankfully everything lined up perfectly. I then used some gutter sealing caulk around the holes on both sides, added some large stainless steel washers on the boat side of the transom, and bolted the unit on with 1/2″ stainless steel bolts and nuts. The caulk spread out the edges of the hardware nice and evenly, so hopefully I won’t have a problem with any leakage.

I then lifted the motor off the transom and onto the tilt unit. Though it only weights 110lbs, it is very awkward to grab onto, so this was easier said than done. One on I clamped it down, hooked up the electrical, and gave it a test. It’s moving! The fun was short lived as I found a problem. The clamping bolts were hitting against the transom when I raised the motor up.

The boat side of the transom with 4 new mounting bolts

The boat side of the transom with 4 new mounting bolts

The tilt unit mounted with the motor tilted up

The tilt unit mounted with the motor tilted up

Clamping bolts hitting the transom

Clamping bolts hitting the transom

As much angle as I can get for now!

As much angle as I can get for now!

Step one to try and fix this problem was to remove the large handles from the clamping bolts. This gained me a few more degrees of lift, but the ends of the bolts eventually hit the transom. I didn’t want to cut the bolts off as it would make future adjustments very difficult. I came up with the idea of threading bolts in from the inside, and then backing them out so the head would press against the mounting bracket, expanding into place to lock the motor in. I tried to find some bolts with the proper thread and found that this thread is not common.

I decided to go with my plan, but with bolts that didn’t thread into the holes for the clamps, but instead just barely slid through them. I put a nut on the side closest to the hole, and the head on the other side, then once the motor was on the tilt unit, expanded the length of the bolt until it tightened against the clamping plate. It seemed to work. I then cut the extra length of bolt flush with the motor’s mounting bracket, and was able to tilt the motor up so the bracket actually sits flush with the top of the transom. Great, but there’s a new problem.

Now that I can tilt it up fine, when I lowered it down I found that the lower bolts that go through the motor mount were hitting against the housing of the hydraulic unit. The solution, raise the motor up one inch. I made a spacer from rock hard Maple to raise the motor higher, drilled two new lower mounting holes in the aluminum mounting plate and tried again. This time everything worked fine. Up all the way, down all the way, no hitting. I’ll eventually replace the wood spacer with some aluminum, but that maple will take some time to show any wear.

Expanding bolt as clamp

Expanding bolt as clamp

Mounting bolt head hits hydraulic unit

Mounting bolt head hits hydraulic unit

A perfect fit at full up tilt

A perfect fit at full up tilt

View from the back with original mounting holes now exposed

View from the back with original mounting holes now exposed

Full view of the motor at maximum upward tilt

Full view of the motor at maximum upward tilt

Full view of the motor at maximum lowest tilt

Full view of the motor at maximum lowest tilt

The 'clamping' bolts cleaned up and the spacer in place

The 'clamping' bolts cleaned up and the spacer in place

The unit comes with a long cable attached to the ‘up-down’ switch, which was long enough for me to route it to the console. I drilled a hole behind the steering wheel and mounted it there. I also ordered an extra switch, the “Transom Mounted Tilt Switch” from iBoats.com that I mounted on my battery box to make tilting the motor at the launch easier. I used some wire splices from True Value to splice the three wires for the switch onto the wires for the original switch so they both work and do the same thing.

Splicing the wires for the extra switch onto the stock wires

Splicing the wires for the extra switch onto the stock wires

Toggle switch is original, other on right is optional add-on

Toggle switch is original, other on right is optional add-on

Toggle switch mounted to console

Toggle switch mounted to console

Transom tilt switch mounted to battery box

Transom tilt switch mounted to battery box

I took the boat back out onto the shallow lake, and it worked great. No leaks, and the motor tilted up and down very easily. The bolts seem to hold things well, no movement or loosening at all. This was an expensive addition, but in the end one I’m sure I’ll be glad I have.

Posted: 08 September 9
Under: Boat
Viewed: 9,661 views

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