DIY solid motor mounts - a different approach

**Myszkewicz** · Oct 28, 2005, 02:02 AM

I don't know if we need another thread in How-to, so I'll just post this here.

This will make a set (front and rear) of VERY solid roll stopper motor mounts. If a bit of engine vibration transferred to the cabin would bother you, this is not a mod for you. If it wouldn't, and you want to get rid of the engine movement that contributes to wheel hop, then read on...

I picked up a set of new motor mounts, and some 2-part urethane mix to fill them with. I'll let the pictures do most of the talking, with only brief descriptions on each...

Front and rear roll stoppers, in stock form.

Cut out the center tube...

Cut the excess rubber off the center tube. A sharp knife helps.

A wire wheel takes the remaining rubber off the metal.

Then use a hacksaw and cut straight across the pressed-in metal insert...

Then use a chisel (or screwdriver) and hammer to peel up the corners...

That should allow you to remove the insert, leaving you with the mount frame.

Do the same on the front roll stopper, and you get this:

Sand the insides of the mount frames to give the urethane better adhesion...

Set the mount down on a flat surface, put the center tube into its approximate place, and start masking off with tape. I chose electrical tape because it's stretchy, your mileage may vary.

Mask one side off completely, leaving the other side open. Use a piece of tape that goes all the way around the piece to hold the center tube in place. Get the center tube as close to the original position as possible. This is important, because you won't be able to move it later. At the very least, get it square and level in there, and protruding from each side equally. Also make SURE you get a good tight fit around the center tube with the tape, or it will leak when you pour in the urethane.

Prime to allow even better adhesion. Let this stuff dry until it's no longer tacky.

Arrange the primed mounts on their side, open side up, suspended so the center tube hangs where it's supposed to. My vise was a handy spot to do so...

Urethane mix. Pour the smaller bottle into the can, and mix for two minutes. Scrape the sides of the can well, you'll need all of this can to fill both mounts.

Then transfer to the supplied plastic container, and mix for two more minutes.

Pour the urethane into the mounts, and let them cure for several hours before moving them.

After a couple days, they should be hard enough to install in the car.

EDIT: After only two hours, they had set up well enough that I could peel off the tape. I'm still going to let them cure a while before installing them in my car, but this is what they look like:

Larger versions of all these pics (even the really blurry one

) are available HERE

Enjoy! Mine will probably go in on Sunday, if I'm not out trick-or-treating.

mojambo · Oct 29, 2005, 12:49 PM

let us know how this goes. I already did this to one of my mounts, (front) but I did not take the rubber out. Also, I had no primer. Let us know whats its, like. AFter a few months, my urethane crumbled a little and fell out when I removed the mount. Hope this works out.

Eric

**Myszkewicz** · Oct 29, 2005, 06:29 PM

What did you use to fill them, the same stuff? Did you prep the surface of the rubber at all? There's a different primer, FL-20, to make the urethane stick to rubber better. I don't know how well that would work with two very different hardness materials.

I don't think I'm going to have any problems with it. It's a solid block of urethane, rather than filling the gaps between the rubber. I thought about doing it that way, but I've read about the DIY stuff coming out after a while when done like that.

**Myszkewicz** · Oct 30, 2005, 11:25 AM

Well, I put the front one in today, and it pretty much eliminated engine movement.

Extra vibration is noticeable when you're first starting the engine, and when you're taking off in first or second gear. Once you get on the road, it's no different. I tried launching a few times (gotta love living by a dragstrip, noone seems to care), and when the tires broke loose, they just spun instead of hopping.

I may end up just leaving the rear mount stock. We'll see. I'll drive it with just the front one in for a while to see how I like it.

So anyway, unless you're going full-on turbo'd drag car, you should probably use something with a bit more give to it. If I end up taking this mount out, I'll probably look for something along the lines of 60 shore, instead of the 94 shore I used this time.

PR_Mivec · Oct 30, 2005, 03:03 PM

^^ very good job
like mojambo i did it with the rubber on (that sounds wierd) but it hant fallen..
looks good and is nice you went the extra mile by taking the rubber out (even wierder)

PR_Mivec · Oct 30, 2005, 03:05 PM

by the way the rear one is a pita to put on and off you might want to saw of that cilinder thingy it has on top make it easy to put on (i really do not see the funvtion of it anyways....)

2k4EvoVIII · Oct 31, 2005, 07:50 PM

So i was wondering how you knew exactly were to put the bolt hole insert? If its not in the exact place you are going to be moving around the way the engine sits and can possibly throw it off enought to cause more problems then good. This happened to me in my 200sx with a SR20DET swap. I had 1 mount that was about 1 inch off and i kept breaking transmissions cases. Once that was fixed it never broke agian.

Its a great idea and i would love to do it if you can tell me how you did it.

Thanx
Chris

**Myszkewicz** · Oct 31, 2005, 08:44 PM

Well, the stock front mount has the bolt hole a little lower than center top to bottom, but centered front to back. I figured as long as I had the bolt hole within the stock mount's range of motion, I was fine. In the end, when I bolted the mount to the frame rail, the center bolt went right in no problem.

The rear mount has the bolt hole centered, which is where I put it when taping the mount for filling.

On another note, now that I've got a couple hundred miles on the front mount, I can say that shifting at high rpms is definitely more precise. I wouldn't have figured engine/tranny movement would make that big a difference when the clutch hydraulics and shifter cables are flexible, but I can tell now that the movement is gone.

WADADLIG_OZ · Oct 31, 2005, 08:51 PM

How much did your parts cost for this DIY?
And great How to BTW...the pics speak for themselves.

WADAD

**Myszkewicz** · Oct 31, 2005, 09:30 PM

A set of new mounts was about $70, and the urethane and primer came out to about $50.

If I didn't need my car for a day or so (and I was *sure* I wanted super-hard mounts), I could have done this for just the $50 for urethane and primer.

MitsuSkot · Oct 31, 2005, 09:56 PM

I did almost the same thing. I used the 80 shore from McMaster. I did both front and back mounts. You nailed it with the cabin vibration right when you start the car. After that, its just a much more smooth power delivery feel. I say do both, because most of the vibration is elminated with just doing the front, i would think that doing the back mount would simply lower the amount of stress the front one has to endure. just a thought.

DallasN2O · Nov 5, 2005, 06:41 PM

Has this improved your 1-2 shift under hard accelleration?

**Myszkewicz** · Nov 6, 2005, 02:18 AM

Quote:

Originally Posted by DallasN2O

Has this improved your 1-2 shift under hard accelleration?

Yes, which was one of the main objectives, other than turning wheel hop into wheel spin. The 1-2 shift is always there now.

DallasN2O · Nov 6, 2005, 01:39 PM

Very cool. Where did you pick up the new mounts? Dealer?

WADADLIG_OZ · Nov 6, 2005, 07:17 PM

Have you gotten used to the vibrations yet or installed the rear mount?

I'm getting some installed soon myself although on my OZ.

WADAD