Rubber Isolators (mounting bow mount)

[EricCO]

My motorguide motor came with these really wimpy rubber isolators to use in mounting the motor to the deck. I'm pretty sure I don't want to use these things. I plan on getting big washers and nylon nuts to mount it since I have easy access to the bow of my boat. Does this sound like the right thing to do?

Do you think I need a washer between the head of the bolt and the Gator II mount?

[Hans]

I have a 60# thrust TM which has a pronounced hum at higher power levels, and I use three sets of isolators. One set between the motor and the top mounting plate, one set between the bottom mounting plate and the top of the boat deck, and one set under the boat deck.

Without the isolators, the hum of the TM was mechanically coupled into the hull of the boat where it seemed to resonate even louder. With the isolators, the hum is just barely audible, even at full power.

Hans

[EricCO]

Hans, I didn't catch that at all! These things are the rubber T's that have a bolt in the bottom of them and when you screw it down it squishes the rubber.

Now, you've intrigued me into what exactly it is your doing. What type of isolators to you have?

[deadrifter]

EriCO,
Motorguide recommends those isolators if you don't have access below deck. They "squish" up and hold the motor in place while isolating vibration. They suggest you cut off the T piece and use the flat part between the motor braket and your deck if you do as you mention, bolting down with nuts and washers.
I have used the T mounts on a couple of alluminum boats and found they held up fine and cut down on motor vibration. They don't recommend them if you have a thin metal deck to mount through but I used 1/2 inch wood backing in the places where that was the case.
dd

[FJH1]

Eric, I use the isolators, however, I dont use the internal nut system that is supplied. I'm actually using a set of the Motorguide isolators with my MinnKota Maxxum. I just clip off the hollow tube section with the internal nut and use my own stainless steel bolts, washers and locknuts. I put the flat isolator between the bottom of the trolling motor mounting bracket and the top of my deck surface. I think the isolators give a tiny amount of dampening. Whether or not this does the motor any good in terms of longer life I don't know, but that's my story and I'm sticking to it :-).

Best Regards,

FJH

[Hans]

Basically it's a sandwich, with stainless washers on each side of a dense foam rubber washer. Designed for shock-mounting electronic equipment. About 3/8" thick overall, 1.75" in diameter, with a 5/16" hole in the middle. Bought them from a ships chandler place in Norfolk, Va years ago when I was in the Navy. You could easily make your own by shopping the hardware shelfs at Home Depot.

Hans

[Jim Carroll]

FJH1 has it exactly right. Do not use the T-nuts as designed if you have access to the underside of the deck. Modify them. Use a bolt, washer, and a nut with the nylon insert and you will never have any problems. JC

[dkooser]

LAST EDITED ON May-02-01 AT 02:55PM (CST)[p]Eric,
Use your own bolts, lock washers and t-nuts as I did. I did put a vibration prevention between the trolling motor mount and the deck though.

I took an old rubber door matt and cut it to fit the outline of where the foot meets the deck. No vibration and fills the voids since my deck is not perfectly flat. You could even use a few mouse pads if they were thick enough.
Dave

[EricCO]

Did you use six bolts? Also which holes on the mounting base should I put the bolts thruogh? I have about six holes running down the mount on EACH side that could be used. Spaced evenly?

[Hans]

I use 8 bolts (4 on each side) between the A.I.O. mount and the forward deck (5/8" plywood skinned with aluminum/carpetted top).

Hans

[Pitts]

Eric I mounted my new excel with the rubber iso's because I cannot get good access to under the bow and they work fine and hold very tight. If you do use one because of hard to reach spot be sure and hand start them before using a power screwdriver because they tend to crossthread real easy.
I agree that the locknuts and washers are better if you have easy access be sure you have a good base of plywood and use some kind of rubber under the gator for vibration.
I think There were only six rubber mounts included in mine did you get eight with yours?
I recieved my replacement pedal today and will send the old one back in the same box with the shipping lable sent to me.
The new pedal came in a box that said it was 2 pinpoint depth finders for hooking into one transducer and my 11 year old had high hopes that they made a mistake and really sent me what was on the outside of the box. LOL

Have fun

Pitts

[Nofish]

Hey Eric,

I have used the T isolators on every boat I have rigged, and they have been on every boat I have had rigged.

They work very well, but I make one small modification. I use thread lock on the mounting bolts. I got tired of the bolts loosening occasionally.

So I went to the hardware store and picked up a tube/bottle of thread lock. Make sure you get the stronger stuff that does not require heat to loosen the bolts. That part is real important.

I mount the motor and then, one at a time, back each bolt out. I apply a small line of threadlock (real thin) down one side of the bolt, about an inch long. Then I screw the bolt back in and snug it up. Repeat on all six bolts.

Since using thread lock, I have never had a bracket come loose and I have never had a bolt back out. I have also been able to remove bolts when needed for various reasons, or trolling motor upgrades.

Have fun....R