DIY: Filling the RX-8 engine (motor) mounts with urethane
08-13-2012, 08:03 PM
#51
Well FWIW I placed mine in the oven following their heating instructions. Bond looks great, edges are stuck on nicely. Honestly on the surface I cannot tell any difference between the mounts I made in the oven, and the leftover urethane that is in the container that has been sitting out for 2 days. No cracking, breaking, or anything like that. I will check them after some longterm use to make sure, but I installed them and took them for a drive and surely feel a difference. Even after a pretty intense driving session, came back home, took a look at the mounts and they were nice and solid, no signs of stress on the surface.
08-14-2012, 07:59 AM
#54
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1) not having a passenger motor mount that is ripped in two pieces.
2)not having to worry about your new passenger motor mount ripping into two pieces
3)saving a ton of cash by making something people sell for over double the price of the DIY
cons
some say added vibration, but people usually only do this when the mount has blown, so I think that compared to a blown mount, the vibrations are far less.
08-14-2012, 08:05 AM
#55
some say added vibration, but people usually only do this when the mount has blown, so I think that compared to a blown mount, the vibrations are far less.
08-14-2012, 09:33 AM
#56
I have 90A urethane filled mounts, solid subframe and some suspension bushings, ultra stiff shocks and springs, etc
you street wussies have no idea what real vibration and harshness is, lol
as for charging people, not everyone is mechanically inclined and when money is involved most people expect something more than just an old dirty looking mount that has been filled with something that can't be seen. It has to be worth someone's effort otherwise there is no incentive to be bothered with it. I explained how it can be done, but also help out those who can't or don't want to do it themselves.
you street wussies have no idea what real vibration and harshness is, lol
as for charging people, not everyone is mechanically inclined and when money is involved most people expect something more than just an old dirty looking mount that has been filled with something that can't be seen. It has to be worth someone's effort otherwise there is no incentive to be bothered with it. I explained how it can be done, but also help out those who can't or don't want to do it themselves.
08-14-2012, 09:45 AM
#57
I would have to say the "hardest" part of the entire process, and I use that term very loosely, is making sure that you don't drill all the way through when making the relief holes (which is pretty difficult to do if you tape up the drill bit per instructions). Other than that there really is no way you can fubar this 'mod' when following the provided DIY instructions.
Just make sure you have the proper tools and dont half *** it.
Just make sure you have the proper tools and dont half *** it.
09-11-2012, 09:13 AM
#58
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Followed the instructions for this last week and re-installed them today. Fantastic write-up and very thorough. My passenger side was half torn open, so I used tape to seal the split until the urethane cured; the only visible difference now is a darker line at the location of the crack. I will re-evaluate the passenger mount in a couple weeks, but as of now I feel very confident in it. Thanks Team for sharing this information!
09-12-2012, 06:14 PM
#62
Finally got to my motor mounts today. The bolts were a COMPLETE pain in the *** to take off. Not much room to play with a big wrench and even with drenching of PB, they seem to be torqued by the power of five turbo'd big blocks.
Both my motor mounts (RH LH) has the inset that seemed to be only for the LH. Though each was individually labeled LH and RH. I prepped the motor mounts for filling, just waiting on them to dry from cleansing. The hardest part was by far getting the bolts loose.
By the way. The motor mounts seem fine prior to cutting/drilling, correct me of I'm wrong. No oil leaking or torn boots.
My idle isn't exactly low in NVH, and it seems to buck a bit more in between shifting than usual. So that made me suspect that my motor mounts were gone, but apparently they're not. I am due for spark plugs, so I'll see if that improves my idle and jerking. I also suspect that my diff mount may be going due to wheel hop.
Both my motor mounts (RH LH) has the inset that seemed to be only for the LH. Though each was individually labeled LH and RH. I prepped the motor mounts for filling, just waiting on them to dry from cleansing. The hardest part was by far getting the bolts loose.
By the way. The motor mounts seem fine prior to cutting/drilling, correct me of I'm wrong. No oil leaking or torn boots.
My idle isn't exactly low in NVH, and it seems to buck a bit more in between shifting than usual. So that made me suspect that my motor mounts were gone, but apparently they're not. I am due for spark plugs, so I'll see if that improves my idle and jerking. I also suspect that my diff mount may be going due to wheel hop.
Last edited by SayNoToPistons; 09-12-2012 at 06:16 PM.
09-15-2012, 02:20 PM
#63
During the drying period, did any of you have urethane expanding in heat? It is now the 2nd day of drying and I rest the mounts by the window in the sun and I noticed that they are ballooning out ~4-5mm in the heat. I assume surface temp is about 115*f.
.
09-17-2012, 01:50 PM
#68
Waiting until tomorrow to slap them in. Tomorrow should actually be the 6th day of drying. I can't imagine it to be too risky to throw it in a day early, because I'm sure the outter most part of the urethane is completely dried. Doubt there will be any separation of material.
09-19-2012, 08:04 PM
#69
I actually waited until tonight to install it, which makes it 7 days. Though like I said, I doubt it would cause any harm to install on the 6th as the urethane's property is ductile.
I didn't have the chance to drive it, but even sitting on stands and doing a bit of revving I can feel a difference. Normally the (untorn) factory oil filled mount would allow so much travel that I can feel the binding from rotational torque from on and off throttle. There is much less of that now. The shifter shows less movement as well. Vibration is minimal. High frequency NVH is increased slightly, but it is actually more comfortable than the harsh low frequency NVH I got from the mounts when they were oil filled.
I had someone go on and off throttle as I looked at the mounts from outside. I notice there is still some compression/tension movements at the upper top part of the rubber cone. I assume this is normal as these aren't solid mounts. Correct me if I'm wrong.
I'll do an update tomorrow when the 8 gets on the road. As of now it is still on jackstands and the motor is resting most of its weight on the jack (with 2x4's of course).
I didn't have the chance to drive it, but even sitting on stands and doing a bit of revving I can feel a difference. Normally the (untorn) factory oil filled mount would allow so much travel that I can feel the binding from rotational torque from on and off throttle. There is much less of that now. The shifter shows less movement as well. Vibration is minimal. High frequency NVH is increased slightly, but it is actually more comfortable than the harsh low frequency NVH I got from the mounts when they were oil filled.
I had someone go on and off throttle as I looked at the mounts from outside. I notice there is still some compression/tension movements at the upper top part of the rubber cone. I assume this is normal as these aren't solid mounts. Correct me if I'm wrong.
I'll do an update tomorrow when the 8 gets on the road. As of now it is still on jackstands and the motor is resting most of its weight on the jack (with 2x4's of course).
09-20-2012, 01:37 PM
#70
Got a chance to drive it hard today. Simply no complaints. Shift feel is improved and has that "shnick shnick" feel especially for 1-2-3. Roll on throttle in 1st and 2nd gear in traffic shows extreme reduction in bucking. Throttle response is obviously improved as well due to less torsional movement. Prior to modifying the motor mounts, it was quite hard to go from a stop and changing gears without bucking. Now the engagement is much easier to modulate. NVH (noise vibration harshness) is as stated before.
I did this without much expectations in any driving experience improvements, so I am beyond content. Keep in mind I used 60A.
I did this without much expectations in any driving experience improvements, so I am beyond content. Keep in mind I used 60A.
11-06-2012, 09:37 AM
#74
05 RX8 Sold///05 Evo VIII
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Anyone else do this? Would like to hear more reviews!
As soon as I pick up an extra set I'm going to do it while my car sits over winter, then swap them in spring. After spring I'll probably do my existing ones to sell.
As soon as I pick up an extra set I'm going to do it while my car sits over winter, then swap them in spring. After spring I'll probably do my existing ones to sell.
11-16-2012, 11:13 AM
#75
05 RX8 Sold///05 Evo VIII
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I got tired or trying to source cheap replacements so I took mine out last night.
Like everyone says, the bolts are on pretty tight. I used some penetrating oil which made it them spin easier.
The trick to getting the bolts out is the correct ratchet. I used my 72-tooth Snap-on 3/8 drive flex head ratchet. The flex head really gives you a lot of le-way. Combine that with a 14mm deep socket. I also have an extra long 14mm box end wrench that has one side as ratcheting. That helped too.
For those who want to do this and let them cure over time or have down-time to let the car sit you have a couple options: Leave the engine and car supported on jack stands.
Or cut some slices of 2X4s and put them in place of the engine mounts.
An exact measurement isn't necessary, I just eye-balled it and cut some little blocks...probably 3-4" in height. With the engine raised up you can fit them in easily and lower the engine onto the small wood blocks.
Here's a pic for reference.
https://www.rx8club.com/attachment.p...1&d=1353086106
Like everyone says, the bolts are on pretty tight. I used some penetrating oil which made it them spin easier.
The trick to getting the bolts out is the correct ratchet. I used my 72-tooth Snap-on 3/8 drive flex head ratchet. The flex head really gives you a lot of le-way. Combine that with a 14mm deep socket. I also have an extra long 14mm box end wrench that has one side as ratcheting. That helped too.
For those who want to do this and let them cure over time or have down-time to let the car sit you have a couple options: Leave the engine and car supported on jack stands.
Or cut some slices of 2X4s and put them in place of the engine mounts.
An exact measurement isn't necessary, I just eye-balled it and cut some little blocks...probably 3-4" in height. With the engine raised up you can fit them in easily and lower the engine onto the small wood blocks.
Here's a pic for reference.
https://www.rx8club.com/attachment.p...1&d=1353086106