filling motor mounts

[mx3_ryder]

My engine moves alot during normal and hard driving and is very jerky between engine braking and accelerating.
Also, my shifter is squeaky which I feel is contributed to the movement of the drive train.
Would filling my mounts fix this problem and which mounts do I fill? Are there any downfalls to filling mounts? Thanks.

[Redline322]

Your back mount takes most of the stress, but unless you fill with good urathane, even filled will not hold up well. These are the best solution: http://store.awrracing.com/categories/E ... -MX%252d3/ The low end duro is close to stock, mid is usually the best for our applications unless you are going for track use only and don't mind vibrations, then the highest duro is your choice.

[Josh]

I have the same issue and have both of those mounts above. I have the shifter bracket and it squeaks excessively. Someone filled the passenger and drivers mount with a paste in an attempt to make them better, but there is a right way and a wrong way to fill a mount. Using paste is prone for eventual failure. My drivers mount is cracked out (even though it is filled) and rocks like crazy. I just purchased new mounts to fill. I get my urethane from McMaster . com. search for casting compounds. 1lb will fill all 4 mounts, I use the 90 shore. I have filled many many mounts, even selling several sets years back. None of them have ever re cracked out, several are still on the road with more than 100K and 8+ years on them.

[mx3_ryder]

Thanks Josh. Is it the general compound you use?
I'm not seeing 90 shore, but for everyday dd use what you'd you recommend for hardness?

[Thefez]

ive used window weld with no problems in the past.. I have over a year on a few of mine. Still stong and no cracking yet. But a 2 part urthane would work best!

[Josh]

Thanks Josh. Is it the general compound you use?
I'm not seeing 90 shore, but for everyday dd use what you'd you recommend for hardness?

Looks like they have changed it up a bit. I would use the general purpose 80A or the 94A

[atx_mx3]

Your back mount takes most of the stress, but unless you fill with good urathane, even filled will not hold up well. These are the best solution: http://store.awrracing.com/categories/E ... -MX%252d3/ The low end duro is close to stock, mid is usually the best for our applications unless you are going for track use only and don't mind vibrations, then the highest duro is your choice.

King6Fab also make a passenger side/main engine mount for the MX-3. It is not listed on his site, but he does make them. I ordered mine last week and it should be arriving any day now. Keep in mind that he hand builds all of the mounts, they are made to order and he is a 1 man show.

As soon as I get that mount in, AWR will see an order from me. I just wish someone would produce a driverside/trans mount for our cars. I will probably be sending in my old trans mount to Darren(King6) to have it fitted with a poly bushing.

[RobMinhas]

Sorry for posting thin the v6 section about this but v6 and I4 mounts are the same for the mx3 right? I'm a big fan of those king6 mounts, would be interested in grabbing some.


And is there any possible upgrade other then the poly bushings for the trans side mount? I'm not a very big fan of that mount at all.

[atx_mx3]

Sorry for posting thin the v6 section about this but v6 and I4 mounts are the same for the mx3 right? I'm a big fan of those king6 mounts, would be interested in grabbing some.

As fas as I know, the I4 and V6 mounts are different, but I could be wrong as I have never owned a 4cyl Mx-3.

And is there any possible upgrade other then the poly bushings for the trans side mount? I'm not a very big fan of that mount at all.

Darren does not want to fab a trans mount for our cars. The design of them is very odd in comparison(to the mx6 and probe) and he is actually trying to downsize on NEW fab projects, so he said in his email to me last week. SO, the poly insert is really the only "off-the-shelf" option.

[RobMinhas]

It seems like the timing belt side looks the same, dunno if they are though.

And that's too bad but I guess gabbing ain't cheap and there probably isn't much of a market for those crooked weirs trans mounts.

[Josh]

From what I know, is that they are all different. But that is what I have always been told, I have never compared them side to side. One could look up the part numbers.

[mx3_ryder]

Fixed my squeaky shifter!!
Thinking of going with a 60 shore or 3M window weld. Should I fill all 4 mounts or just the torque mounts?
Anyone ever tried silicone?

[davmac]

Silicone would be a waste of time - way too soft. I've never used 3M window weld, but it is polyurethane and should work ok. The problem is that you must let it cure. Window weld is air cured and cure time is temp dependent. Window weld is not usually applied so thick as when you fill a mount. It will take a long time, at least 24 hours to cure where you might re-install and probably longer to cure entirely.

The urethane casting compound is the way to go. It is a chemical cure and ready for use within a couple of hours. Don't be afraid of the higher number durometer. I've got some AWR mounts in 88 durometer and have no issues with vibration at idle. The v6 is a very smooth running engine when it is running properly.

[Daninski]

Thanks Josh. Is it the general compound you use?
I'm not seeing 90 shore, but for everyday dd use what you'd you recommend for hardness?

Looks like they have changed it up a bit. I would use the general purpose 80A or the 94A

If you go with the 94A I suggest you drill two opposing 1/2 inch holes in the rubber to allow a little flex. My dash would vibrate at idle because with 94A your mounts will be very very stiff. Clean your mounts well and sand the existing rubber first before filling.

[mx3_ryder]

Appreciate the extra info guys. My problem is picking a hardness as I don't want the dash to vibrate to pieces, but davmac has a great point that the V6 engine is very smooth idler. I'm going with the 80A shore compound from Mcmasters-Carr.
Just going to order right through my work as we have an account with them already. Is this compound really ready to use in just a few hours cause I read it still takes 48 hours to fully cure and I will be filling in one shot, not in layers?
Also guys, should I fill all 4 mounts?