Installing polyurethane motor mounts.

[97GSTspyder]

NOTE: These are instructions for eclipses with the 4G63 engine.
In this post I'm going to describe, the best that I can, on how to install upgraded (polyurethane) motor mounts. Hopefully this will help a lot of you. This is another long one guys. After this is posted no one should be asking "how do i install these motor mounts i just bought?". Sorry there are no pics, but I described everything the best that I could. It's really not that hard. I'll try to get some pics soon.

If you have a full motor mount set, there should be a total of 8 "plastic looking things". These will be replacing your crumby stock rubber mounts. Keep in mind, you have 4 mounts, not 8. 2 "plastic things" per mount. If you haven't already figured that much out. If you are going to attempt to replace your mounts, READ THIS POST from start to finish! I am not held responsible for any mistakes/damage!

Now, I'd say the hardest ones to do would be the transmission and rear roll stopper mount. These aren't all that easy to do. I will explain the two simpler ones first. I will go in order from easiest to most difficult (from my experiences). The main things that I tell people are - take your time, be careful, use only good jacks...Not the ones that have been laying around for 10+ years and have rust all over them. And don't be afraid. You more than likely won't mess anything up.

Now for the first, and simplest mount install. You're going to want to jack up the motor, to take the stress off of the mount 'through-bolt'. For this first one, the car doesn't need to be jacked up, unless you can't fit your jack under the motor. Take your jack and put a block of wood on top of it. Place it underneath the oil pan. MAKE SURE there is a wood block on the jack! You don't want to dent/ding the oil pan. That wouldn't be good. Now slightly jack up the motor. You don't need to be cranking that jack 20 times. Once you have the stress off the bolt, time to take it out. Now take a 17mm socket (i think) and a rachet. Lefty loosey, righty tighty. Try to get that sucker out. It'll probably be torqued pretty good. If it won't come off, use a breaker bar. If you don't have an actual breaker bar, use a pipe to put on the rachet. Anything to make the lever longer to provide more torque. Once you break it loose, pull it out. It should come out pretty easily. If not you either didn't jack the motor up enough, or jacked it up too high. Once you have that through-bolt off, take the two nuts off the mount. They are by the timing belt cover. I believe they are 15mm, not sure though. Once you've done that, pull the mount off. Now comes the fun part. Trying to get that rubber mount out. If you feel that you can't do it youself, take it to a shop. It's like $10 to pull it out. I did mine myself and believe me, it is a bitch to get that rubber mount out. After it's out, pop the new polyurethane mount in, and installation is easy.

The second mount, and also a pretty simple one, is the front roll stopper. It's below the turbo, attached to the crossmember. For this one, you will need to jack up the front end of the car, and after that jack the motor up exactly like i mentioned before. Now grab your kreeper (or whatever else you use to lay on) and slide yourself under the car. The crossmember is that big long bar that runs from the bottom of the radiator to the back, underside of the motor. As soon as you get under the car, look up and you should see it. It has the same black rubber as the last mount. To take the through-bolt out, you'll need a 15mm socket (i think), and rachet to go with it, and the same size wrench. Place the socket on one side, and the wrench on the other. Do whatever you can to break the bolt loose, just don't strip it. Once it's broken loose, take the bolt out. Now there are two more bolts to be taken out. These bolts attach the mount to the crossmember. Look right under the mount, on the crossmember. There should be two holes in the crossmember. I believe they are 15mm also. You'll need a socket, rachet and an extension. Break those loose, and the mount should come right out. Once you have the mount out, leave the stock rubber in there. The polyurethane mounts you have for this one are just inserts. There are two of them. Pop each insert into each side of the mount. That's it. Place the mount back up in there and bolt it back up.

Now the two hardest mounts. I had to decide which one was harder, the rear roll stopper or the transmission mount. I came up with the rear roll stopper as this one. If you're going to do these two mounts, you're gonna need at least a pack of cigarettes (even if you don't smoke...it's just that damn stressful lol), tools and patience. For the rear roll stopper, you don't need the front of the car jacked up (unless your jack won't fit, like i said before)...Jack up the motor either from the oil pan or transmission. Either way, USE A BLOCK OF WOOD! You'll be working from the top of the car on this one. And you'll probably be sitting in your engine bay trying to get this fucker out. It's no fun. But hey, if I can do it, almost anyone can. Just take your time with it. Now on to the details. Got your motor jacked up just enough to relieve the stress on the through-bolt? Good. This mount is located behind the motor, bolted to the opposite end of the crossmember. Start taking some shit out. Your battery and tray, the hose that runs from the UICP to the throttle body elbow, UICP might help if it was out, and anything else that gets in your way. NOTE: I figured if you're going this far, now would be a great time to replace the fuel filter. Anyway, once you have everything cleared out of the way, see the fuel filter? The mount is to the right, and below it. Right on the crossmember. The trick is getting your rachet and a wrench in there to disconnect the through-bolt. I believe they're the same size as the front, 15mm (i think). (Sorry about the guessing, but it's freezing cold here and i don't feel like going outside, heh). Ok now just find a way to get the wrench on one side of the bolt, and the rachet on the other side. I know, it's hard but just do whatever you need to do. Got them on the bolt? How about now? Now? .........Get it yet? lol ok, now you'll probably have to use a pipe again to break the bolt loose. Attach the pipe to the end of the rachet, usually the pipe won't fit on the wrench. I find it easier if i have the rachet on the fuel filter side, and the wrench on the other side. Do whatever you can to break that sucker loose. Once you got it loose, get the bolt out. After that, there are 3 more that attach it to the crossmember. Same size I believe. These aren't as hard but you'll need an extension. Get all those off, and find a way to get the mount out of there. This is harder than it sounds because you have the shift cables right above the mount coming out of the firewall. And they don't like to bend very much. Do whatever you can to get the mount out. Once out, do the same thing you did with the front roll stopper. Pop in the inserts, then find a way to get the mount back down in there, straighten it out, bolt it up and you're set.

Now for the final, and most difficult mount. The main transmission mount. The reason I made this last and say it's the hardest is because once you get all the bolts off, you have to find a way to get the mount off the studs and clear the part where the mount aligns to. Jack up the tranny, USE A BLOCK OF WOOD! Jack up the tranny just enough to take the stress of the transmission through-bolt. I believe the through-bolt is a 17mm and the other ones are 15mm i think. Break that through-bolt loose. You'll need to use a rachet and a wrench on each side. Use the wrench on the firewall side, rachet on radiator side. You'll probably have to use your breaker bar to break it loose. Get it loose and take it out. If it won't come out, play with the jack a bit. Get it out, then work on the other bolts. I think there are 3 or 4 of them. You'll probably need an extension if i remember correctly. After you get all these bolts out, you can't just take the mount off. This is why I put this as hardest. You can move it around a bit, but the studs on the tranny is what is keeping it on because it won't clear. You can do whatever you want to get this mount out. You're going to have to lower the tranny, and possibly some of you might want to even remove the crossmember. This is why I said read this whole post before attempting! It would be pointless to have re-connected the front and rear mounts if you're taking the crossmember off. NOTE: If you do take the crossmember off, it is IMPERITIVE to have the motor supported at ALL TIMES. Do whatever you have to do to lower that tranny enough to pull the mount off the studs. Once you finally get it off, do what you did with the main engine mount. Somehow get the rubber out and get the polyurethane ones in. After that is said and done, put the mount back on the studs, jack up the tranny, align everything and bolt it back up. Reinstall the crossmember if you removed it.

Make sure all of the mounts are secure and tight!
Make sure everything else is reconnected!
She's ready to roll!

NOTE: After installing these mounts, you will notice that your car vibrates a lot more now. This is perfectly normal! There is nothing wrong with your car. This is because all of that engine vibration is now being transferred into the cabin. Now be happy knowing that your motor doesn't move around as much! Also, I don't know how true this is, but my mounts claimed to 'add more wheel horsepower' since the engine doesn't vibrate and move around as much anymore, allowing more HP to reach the wheels.

Good luck.
Now that my hands hurt from typing, it's time for a cigarette.

Your friendly AF friend,
Steve

[david-b]

May I just add, if your car rattles alot after doing this mod, buy some dyno-mat and do the parts that are rattling. Also, tightening up some screws makes a world of difference with some rattles.

[T38]

Great writeup, but I still have one question

How did you break the inserts out of the mount? I decided to replace my mounts while replacing the clutch on my Talon, but I'm having problems getting the #@#$!!! inserts out. Did you have to buy/rent/steal (just kidding) a tool to press the inserts out, or were you able to piece something together to do the job? Or can you cut the rubber inserts out and then grind the steel insert out?

Thanks!

--Mike

[97GSTspyder]

the only ones that you take out are the main tranny and engine mount....i used a torch, screwdriver and i think scissors to get it out...they are a bitch to take out, just keep working at it.

[JoeWagon]

Bump once more since unstickied. Hope I don't see any of these install questions. FAQ'd.

[kjewer1]

10 bucks at the machinist is a lot more efficient than fisting the mount for 30 minutes to get the stock sleeve out. 2 mounts for a 2g, 20 bucks, 3 for a 1g, 30 bucks. Shit, even I'm not that cheap! Just notices thats in the write up, never mind.

The through bolts for the front and rear are 14mm, the through bolts for the two side mounts are 17s. The tranny one has a nut as well, the drivers side does not. The tranny side mount is held to the tranny by 4 17mm nuts. The drivers side is 2 17mm nuts and a 14mm bolt. The rear is 3 17mm bolts into the tranny (ratcheting box end works WONDERS here). The front, well that doesnt have to come off. Drop the cross member instead, a handful of 14mm bolts at the K member end (With the triangular gusset) and 2 17mm bolts at the radiator support (front) end.

To get that tranny side mount to clear the studs better, leave off the front, rear, or both mounts, supporting the tranny by a jack as suggested. That gives it more range of motion to drop a little lower down so the mount body can clear the studs.

Rather than put the jack under the oil pan at its lowest point (where the oil pump pick up is inside ) I prefer to put it under the tcase for AWDs. For FWDs that part of the pan where the tcase WOULD be, should be exposed. Put the jack there. Its much stronger there, and if you dent it a bit it wont affect the oil pump pickup (=crankwalk).

When pulling out that rear mount (part with 3 bolts to the tranny), take care not to smash the shit out of that 2g speed sensor. 1g is cable driven and a lot less fragil, and it doesnt come up through the middle of a mount in the first place. 2Gs suck

Edit> Bolt numbers/sizes/locations given are for 2Gs. Almost forgot about you 1G wankers. The front mount will not be on that longitudinal crossmember, but on the later one used in 1Gs. The other half os on the motor, 17mm bolts. The rear is also on the block and not the tranny, also 17mm bolts. That one is so long though, you could probably just roll the motor forward if you had some other mounts undone. The other hald is bolted to the K member with 3 (?) 14mm bolts that always like to break. I tend to not do the rear for this reason. Unfortunately, unlike the 2G, the rear one is not a "insert," but a full replacement like the two side mounts.

The original write up is good enough, and it seems like I've gone and overly complicated things now. But some poeple might find the added detail useful I suppose... Moral of the story, its not a bad job, just do it

[97GSTspyder]

awesome...thanks for the added advice kevin. hopefully people will find all of this information useful.

[kjewer1]

I hope so! Thats why we waste our time with this BS

[matt50317]

i had some polyurethane mounts installed, but when i recieved them i was given the wrong front motor mount and so i had to go to several diffrent auto parts stores and then to mitsu to get the right size, but the problem is that my front motor mount isn't polyurethane. now does that effect any thing?

[Blackcrow64]

Originally Posted by matt50317

i had some polyurethane mounts installed, but when i recieved them i was given the wrong front motor mount and so i had to go to several diffrent auto parts stores and then to mitsu to get the right size, but the problem is that my front motor mount isn't polyurethane. now does that effect any thing?

Yeah, your motor will torque funny now and you will probably end up busting out the stock rubber insert to it.

[4g63gst20]

ohh shit i never knew this was a sticky, this will help on my install.

[Black99GST]

Great info! makes me want to get new motor mounts... but i dont know if they are worth it...

[Blackcrow64]

Originally Posted by Black99GST

Great info! makes me want to get new motor mounts... but i dont know if they are worth it...

Well worth it man. I had my new clutch put in and everytime I shifted it woudl torque the motor horribly. I put in the polyeurothane motor mounts and had no problems after that. Its worth every penny.

[matt50317]

i have one small question, I install the poly motor mounts but when i got the mounts i didn't get the front mount, so i had to buy a stock one. But where can i buy the front poly mount at?

[gthompson97]

Well where did you get them from, because you should have gotten the front one too.