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Urethane Motor Mounts

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48K views 140 replies 62 participants last post by  1ccs-todd  
#1 · (Edited)
Off the bat you should know this is something that you can't just do and drive immediately. If your tib is your daily driver, you'll need to get a second mount from somewhere else, as this takes about 2 days to completely set. I did this with a mount I purchased off of another NT member so I could still drive my car. The materials (assuming you already have the tools) will run slightly over $35 if you use your current mount, and supplies you enough to do 2 mounts and still have some scraps left over.

I wrote this originally assuming that you would know how to take the motor mount out, as it's mentioned several times in several other threads.

First, I started with the stock mount.

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You'll also need 2 junk CDs, I just used the CD shaped plastic that comes at the top of the spool.

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The material I used was ordered from Mc Masters, www.mcmaster.com part number 8644K11.

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I also used a piece of copper pipe, I just took the old mount to Lowes to get a piece of pipe that was the same size as on the stock mount.

Step 1 - Cut out as much of the stock rubber as you can. It's ok if you leave some in, the urethane will adhere to the rubber as long as you scuff it up with a dremel or something similar.

UnHolyTib also suggested this, seems like a real good idea to me too:
I have been making these for years, and the one in my car has been in there for 1000's of miles and holds up fine..

Here is the easiest way to reuse the center peices, take a torch ( cheap propane ones) and heat the insert until it melts the rubber around it, then it just slides out... ( the rear one is larger inside the rubber than it appears, heat it a lot)

The size of the front mount is 15/16 get a widow maker bit ( wood bore) and it goes right thru and makes a tight fit.

If you put the mount in a vice, you can run a hack saw around the edges, and remove almost all of the rubber, then heat the remaining rubber with the torch and scrap off with a butter knife...
CiZiN also added this:
1. To fully cut out the center, I used a new long blade on a saber saw. This made short work of the rubber and I could cut it to within mm of the metal.

2. Instead of using a cd to cover the other side. Use Duck Tape. It allowed for a good fit and nothing leaked out.
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Make sure you clean it as much as possible and make sure there is no oil or grease or grime before the next step. I used Purple Power degreaser, I did not dliute it with water. Allow it enough time to dry.

Step 2 - On a piece of tin foil, lay the CD and the mount, keeping it as flat as possible. I let the mount hang over the edge of my counter. If you have it handy, I recommend rubber cement or duct tape around the edge of the mount and the CD to help prevent leakage. After the cement dries or you have it sealed up with as much tape as you can, it's time to mix up the urethane.

They send you enough to do 2 mounts as I said, so if you're only going to do one at a time, get a throw away tupperware container and pour half of the bottle and half of the can into the tupperware. If you're doing both at the same time, then you can pour the whole bottle into the can.
BE CAREFUL!!!! When I did this step, the top of the bottle popped off right into the can. Lucky for me, I was mixing up the entire batch.

Step 3 - Pour the urethane into the mount, up to the top.

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Take the second CD and place it on top. Find something to weigh the mount down and place it on top of the CD to help make sure the mount stays level. Some may seep out of the bottom a little, so you may want to use rubber cement to stick the CD to the mount and wait until it dries to help contain it. After the mount is 100% finished it'll peel off easily. Without that, not a lot seeps, but it is enough to drip onto a rug if you don't have it covered.

The instructions say the urethane is usable after 24 hours, but because of the thickness of the mount, I let it sit for 3 days to make sure it hardened properly.

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Step 3 - After the urethane has hardened fully, drill a hole through the center. I used a drill bit about the size of the bolt, and it was still too small so I had to twist it to widen the hole some. Press the pipe through the center. It should be very very tight.

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Trim the pipe as needed, my dremel worked fine for this, just took a few minutes. I trimmed it to the same length as the stock mount. And now it's ready to install, and you have a full urethane mount (or 2 if you decided) for under $40.

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#3 ·
Re: Full (almost) Urethane Mount DIY

I've had it on for a few days so far and it's holding up fine. I did this with my old car (99 Chrysler Sebring, V6) and it held up great for the 2 years I had it. I haven't had a chance to do any distance driving yet, but I've been checking it to see if it softens up any with the heat.
 
#5 ·
Re: Full (almost) Urethane Mount DIY

Been running this for a few weeks now, with no problems. Over the last week, I've had my headers in as well, and there are no adverse effects. it works great, and if you've got a spare mount laying around for some strange reason, you can do it without any downtime to your car.
 
#10 · (Edited)
Re: Full (almost) Urethane Mount DIY

Wow, that's amazing. :m_thumrig

One of my Prothane inserts squeak (the rear one), it's driving me crazy, so I think I may do this for both. I like this DIY a lot.

Can you cut out the center piece of metal and mount it into the replacement? Like after you cut out the stock center, use a dremel tool to get that center spindle out?
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And then pour the liquid urethane around the metal center spindle. The main reason I ask is because copper is quite soft, I'm not sure how durable that would be. Do you think that would work?

Also, what did you use to de-grease the stock mounts before pouring in the urethane
 
#11 ·
Re: Full (almost) Urethane Mount DIY

If you wanted to take the time to do it I'm sure you could get the rubber from around the center spindle. Problem is, it's very thick at that point, so it'll take a lot of work and patience.

Also you;d have to construct something to hold the spindle in place as it dried, since it sticks out further than the edge of the mount. I just used the copper to give the bolt a nice smooth place to fit into, and so the bolt didn't rub along the urethane and make the hole wider over time. It's pretty solid, but it's a just in case type thing. I've had it in for a few months now, and I drive 45 miles to work each way and have no problems.

I used Purple Power degreaser, but any will work. Ijust happened to have a gallon jug of that laying around.
 
#12 ·
Re: Full (almost) Urethane Mount DIY

Sorry for all the questions, but I like to have a clear idea of what I can expect before I do a project like this... anyways:

Did you use a jig-saw or a reciprocating saw to cut the rubber, or did you do it by handing using a razor or something else. How hard was it to cut? Did you have a problem with the urethane sticking to the CD?
 
#13 ·
Re: Full (almost) Urethane Mount DIY

It's all good, that's what we're all here for anyway, right?

I didnt have many tools when I did it since I had just moved, so I just used a combination of my dremel and heavy duty wire cutters. You have to cut a little chunk at a time, but it went pretty fast.

The CD sticks a little bit, but as long as you wait until after it's dried at least 24 hours it'll peel off pretty easy since it flexes. If you noticed the one pic that the urethane looks real shiny, that was the part that the CD was against.
 
#15 ·
Re: Full (almost) Urethane Mount DIY

have an idea to make it much simpler and don't make it much less effective. by the way when dremeling out the rubber, maybe leave 2 legs of stock mount and dremel them a bit, so you leave the centerpiece without any negative thought of moving and disaligning the center part..? or am I wrong?
 
#16 ·
Re: Full (almost) Urethane Mount DIY

I have been making these for years, and the one in my car has been in there for 1000's of miles and holds up fine..

Here is the easiest way to reuse the center peices, take a torch ( cheap propane ones) and heat the insert until it melts the rubber around it, then it just slides out... ( the rear one is larger inside the rubber than it appears, heat it a lot)

The size of the front mount is 15/16 get a widow maker bit ( wood bore) and it goes right thru and makes a tight fit.

If you put the mount in a vice, you can run a hack saw around the edges, and remove almost all of the rubber, then heat the remaining rubber with the torch and scrap off with a butter knife...

These are the exact same compound used by all other manufacturers, no worries on them holding up... There was a point where I even considered making them and selling them...
 
#17 ·
Re: Full (almost) Urethane Mount DIY

Stupid question on my part, sorry in advance!!

What would happen if you just poured the Urethane into the mount "as is"? Wouldnt it save the hassle of just burning and cutting?

Actually scratch that question, i just realised that the rubber surrounding the center piece would eventually wear away.
 
#18 ·
Re: Full (almost) Urethane Mount DIY

Ranier - nah at idle you feel vibration in the steering wheel but after you egt past about 1000 rpms it's gone.

apkraven & didz - If you did that I think when the rubber flexed it'd start pressing the urethane out, since it's so much stiffer.

Uhnoly - that's a great tip, I never thought about that.
 
#19 ·
Re: Full (almost) Urethane Mount DIY

I was wanting to do this, and found a couple more threads about it for other cars, such as this one:

http://www.superhonda.com/forum/showthread.php?t=204274

I read about someone using 94 or 96 shore (hardness scale) and it was too much and that if he was to do it again he would use 60 shore. I also read that a lot of people were using the 60 shore as well. Would the 60 shore be a better choice than the above mentioned 80 shore? Or is 80 deffinetly the way to go? Thanks!
 
#20 ·
Re: Full (almost) Urethane Mount DIY

I'm using the 80 that I listed, when I asked another company for their recommendation they told me the 60 may soften too much with the heat. I haven't had any probems at all and once you pass idle, you get 0 vibration. Every application will be a little different though, I went with this since the mounts are so close to the exhaust.
 
#21 ·
Re: Full (almost) Urethane Mount DIY

I asked shark racing what theirs were rated at...they said the red urethane that companies like Energy Suspension sell are rated at around 75 or so, and that theirs is rated at 90-95 about. So the 80 shore seems like a good choice.
 
#24 ·
Re: Full (almost) Urethane Mount DIY

xFloggingkylex said:
anyone have spare mounts and want to make me a set? Also, for 03's. do they have the same mounts for front and rear? it was after 03 that the rears look different right?
I have a front, not a rear though. And as for the 03, I'm not sure but on the 04 the front and rear are different.
 
#25 ·
Re: Full (almost) Urethane Mount DIY

if the 03's are the same front and back, is there any way you could fill the one you have, send it to me, and when I get it, I'll send you my front, then you fill that and sent it to me, and I'll send you my rear? that way I'll get 2 filled mounts, and you'll end with a stock mount, and however much money you decide to charge. If you are up for it, let me know. if the price is right I'll do this for sure.
 
#26 ·
Re: Full (almost) Urethane Mount DIY

xFloggingkylex said:
if the 03's are the same front and back, is there any way you could fill the one you have, send it to me, and when I get it, I'll send you my front, then you fill that and sent it to me, and I'll send you my rear? that way I'll get 2 filled mounts, and you'll end with a stock mount, and however much money you decide to charge. If you are up for it, let me know. if the price is right I'll do this for sure.
Let me look into costs and I'll get back to you on that.