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Collapsed Motor Mount/Vibration

Old 07-18-2012, 07:15 PM
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Ok... So I started this DIY last night, and decided to drill the holes in the mount today. I tried to be very careful, but just went a little too far on one of the holes and went through the rubber. It's a tiny hole, but I wanted to know if I can either bond it up with something, or will the urethane just fill in the hole anyways?

Luckily this was an extra mount I had lying around, so it's just a test mule for this DIY so I don't mess up on the real thing since I'll have to have my car out of commission for a week when I do the real thing.

As for that, can I just lift the engine with the floor jack method and 2x4's , then use two jack stands, one at the end of each pan, to rest the engine on? I'd place 2x4's in between the oil pan and jack stands just so the jack stand doesn't go through the pan. Lol
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Old 07-19-2012, 10:53 PM
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Old 11-18-2013, 06:28 PM
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Good to use?

Are these still ok to use? I got them off of ebay pre-filled 85a for pretty cheap.

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Old 11-18-2013, 10:17 PM
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If they were cleansed and filled correctly, they're fine.
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Old 11-19-2013, 05:01 PM
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Originally Posted by SayNoToPistons View Post
If they were cleansed and filled correctly, they're fine.
Thanks bud.
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Old 02-19-2014, 07:17 PM
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CA Rebuilt Mounts

On my 04 manual, i have replaced the mounts with BHR medium stiffness inserts. It eliminated the shifter shake, but now have a light vibration in cabin. I exchanged inserts to low stifness and now have no vibration. I rebuilt the stock motormounts with shore 80 neoprene and painted with black Plastic Dip .they can be had for $60. + shipping SOLD

Last edited by Trackrat; 05-18-2014 at 02:46 PM. Reason: added info
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Old 10-08-2014, 04:23 AM
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Hi all, When drilling out my LH engine mount I somehow managed to go slightly through the rubber top hat. I was wondering if anyone could give me some guidance as to whether it is still usable or if I need to source another one to fill with urethane,

Any help appreciated!
Attached Thumbnails Collapsed Motor Mount/Vibration-image.jpg  

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Old 01-09-2019, 07:51 AM
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Long term damage from collapsed MM?

I believe the problems I'm experiencing are related to the motor mounts. Issues started about 3-4 weeks ago.

I'd like to spring for nicer/performance mounts, versus oem, but would need another 2weeeks.

Anyone have input on delaying the repair? Or should I just get the cheap stock mounts now and risk any long term damage.

i should add that I daily drive my RX-8, about 400 miles per week.
Thanks everyone!

Last edited by MrRawrRawr; 01-09-2019 at 08:07 AM. Reason: Adding more detail
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Old 01-26-2019, 09:23 AM
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Let me add one thing to Team's excellent urethane filling instructions. If you do not want to leave your engine on a floor jack for a week, you can press fit pieces of 2x4 into the spaces normally occupied by the mounts and set the engine down on them. S2 cars have a somewhat fragile oil pan configuration, and even though I put lumber across it to more evenly distribute the weight, I did not want to leave a jack under it for 8 days.

Here are some photos from when I did mine.

Drilled, washed, and blown dry with compressed air

Repainted, taped, ready to fill


Still filled

My procedure was a little bit different than Team's. Instead of using solvent, I soaked mine in a bucket of Joy detergent and hot water. I changed the soapy water and soaked them again, then rinsed thoroughly with hot water. I also taped mine, so I could pour about 1/16" extra urethane. That allowed me to file the urethane level, as the mounts do not sit level when turned upside-down. The extra material enabled me to precisely control the finished height. When I was finished working them, I beveled the edges with a sharp knife. I pulled the tape off after about 6 hours of cure time, then waited 7 days before working with them again. It has been a year, and they are performing very well. There is some added NVH, but it is isolated to under 2K RPM and isn't bad.


Last edited by Steve Dallas; 01-28-2019 at 09:14 AM.
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