motor mount questions

[rit14623]

I was changing out the ATF in my car this weekend and inspected the motor mounts. The driver's side and passenger's side motor mounts look fine. The front motor mount rubber had a look of dry rot but was not fully torn. I couldn't get a good look at the rear motor mount. I ordered some Corksport motor mount inserts for the front and rear.

1. Should I get a new front motor mount if the rubber on the motor mount is worn or will the insert just hold up inside the old motor mount?

2. The instructions to replace the rear motor mount or to install inserts looks like a pain in the butt; that entails removing the strut tower bar, battery, throttle body intake tube, cutting a bolt sticking out of the firewall with a Dremel tool, removing three nuts from the motor mount-to-cross member bolts and then removing the motor mount-to-bracket bolt. While underneath the car, I saw this bracket with three bolts connected to the transmission and the top part of that bracket had one bolt going through the rear motor mount. It looks easier to keep the motor mount bolted to the cross member and then just remove the three bolts from the transmission bracket, the one bolt from the motor mount-to-bracket bolt from underneath, stick in the motor mount inserts and reinstall the bolts. Anyone else did it this way?

 

[lostmybook]

I just did my motor mount about 2 months ago. Indeed, it was highly inconvenient to do. I don't get what you're saying about the mount-to-crossmember bolt and mount-bracket bolts. I didn't do it like you mentioned, I just removed the whole intake manifold. I ended loving all the work space it frees up. If you've taken the IM out before, it won't be that difficult to do. The most difficult things to do for me were 1) cutting the firewall bolt. I didn't have access to a dremel that could fit under there without damaging anything else, so I sawed it off by hand. 2) Removing the three 17mm crossmember bolts. It was hard to get a good angle on it to get some good torque on it. That was solved using a 1/2 inch breaker bar with a universal joint (I tried using a cheap breaker bar that was flimsy). Other than these two, with the IM off, it was just like a regular mount install. Just in case you want some pics to familiarize yourself with the situation, here was my thread about it.

http://www.mazdas247.com/forum/show...Engine-Mount-The-Current-Bane-of-My-Existence

Hope that helps!

 

[Installshield 2]

those asshole studs that hold the plastic harness bracket thing...I just ripped them out by hand with a pair of vice grips...It took such little force to do, its obviously pointless to have that bracket mounted there anyway...just very slight tension on the harness would have popped them off anyway. I was simply trying to bend them slightly out of the way at first, and it came off...whatever though, easily one of the lamest designs i've come across on these cars.

I just filled the holes with instant gasket maker stuff (i've read even that is overkill, as they don't even go into the true firewall, its just a thin metal sheet in front of it)...and left the damn thing dangling back there above the mount. 9 years later...not one problem related to that haha.

 

[rit14623]

I just did my motor mount about 2 months ago. Indeed, it was highly inconvenient to do. I don't get what you're saying about the mount-to-crossmember bolt and mount-bracket bolts. I didn't do it like you mentioned, I just removed the whole intake manifold. I ended loving all the work space it frees up. If you've taken the IM out before, it won't be that difficult to do. The most difficult things to do for me were 1) cutting the firewall bolt. I didn't have access to a dremel that could fit under there without damaging anything else, so I sawed it off by hand. 2) Removing the three 17mm crossmember bolts. It was hard to get a good angle on it to get some good torque on it. That was solved using a 1/2 inch breaker bar with a universal joint (I tried using a cheap breaker bar that was flimsy). Other than these two, with the IM off, it was just like a regular mount install. Just in case you want some pics to familiarize yourself with the situation, here was my thread about it.

http://www.mazdas247.com/forum/show...Engine-Mount-The-Current-Bane-of-My-Existence

Hope that helps!

Okay. Thanks for the link.

To answer your question, those instructions about removing the strut tower bar and battery and intake tube are from Corksport. From below the car, I could see two pieces of the transmission mount. The upper mount has three triangular positioned holes that mounts on top of three cross-member bolts. The upper mount is the part that houses the rubber part and where the polyurethane inserts go into. The lower mount has three holes in a line that mount to the transmission and a fourth hole at the top which connects to the other transmission mount piece. If I remove the lower mount, then I can simply insert the polyurethane inserts into the upper motor mount and not have to deal with removing a whole bunch of stuff from above and remove the firewall bolt.

 

[Installshield 2]

Okay. Thanks for the link.

To answer your question, those instructions about removing the strut tower bar and battery and intake tube are from Corksport. From below the car, I could see two pieces of the transmission mount. The upper mount has three triangular positioned holes that mounts on top of three cross-member bolts. The upper mount is the part that houses the rubber part and where the polyurethane inserts go into. The lower mount has three holes in a line that mount to the transmission and a fourth hole at the top which connects to the other transmission mount piece. If I remove the lower mount, then I can simply insert the polyurethane inserts into the upper motor mount and not have to deal with removing a whole bunch of stuff from above and remove the firewall bolt.

I'm a little confused too. The driver's side mount is on top of the gearbox, which you are pointing out. Nothing bolts to the firewall at that location though, it just bolts to part of the sub frame on the driver's side of the car... and is it really easy to access all that from under the car? I know you can see it easily, but getting wrenches and everything around the gearbox from below seems needlessly tedious...in my opinion at least...

so just clarifying...the only mount any where close to the firewall is the rear mount...and thats by far the hardest one to deal with. As far as the transaxle mount (which is what you are talking about)...I would highly recommend just taking the 10 minutes to remove the air intake/filter housing and the battery (that may not be necessary though)...and accessing that thing from the top...those bolts and nuts are all torqued pretty tight...and will be pretty seized up if you haven't done this recently...by trying to twist around from underneath i'd imagine it being a lot easier to round off or strip something things...which will end up creating a lot more work for you. Its your call, it just seems like we are talking about two different mounts...the rear mount through bolt is very accessible from underneath, but at least with a manual gearbox...the driver's side mount is kind of accessible, but less so than from above.

remember to support the engine in some way, and be able to lift it slightly to take the weight off the through bolt of the mount...if not, you'll have a hell of a time getting it out...and back in again once the inserts are in place.

 

[rit14623]

I'm a little confused too. The driver's side mount is on top of the gearbox, which you are pointing out. Nothing bolts to the firewall at that location though, it just bolts to part of the sub frame on the driver's side of the car... and is it really easy to access all that from under the car? I know you can see it easily, but getting wrenches and everything around the gearbox from below seems needlessly tedious...in my opinion at least...

so just clarifying...the only mount any where close to the firewall is the rear mount...and thats by far the hardest one to deal with. As far as the transaxle mount (which is what you are talking about)...I would highly recommend just taking the 10 minutes to remove the air intake/filter housing and the battery (that may not be necessary though)...and accessing that thing from the top...those bolts and nuts are all torqued pretty tight...and will be pretty seized up if you haven't done this recently...by trying to twist around from underneath i'd imagine it being a lot easier to round off or strip something things...which will end up creating a lot more work for you. Its your call, it just seems like we are talking about two different mounts...the rear mount through bolt is very accessible from underneath, but at least with a manual gearbox...the driver's side mount is kind of accessible, but less so than from above.

remember to support the engine in some way, and be able to lift it slightly to take the weight off the through bolt of the mount...if not, you'll have a hell of a time getting it out...and back in again once the inserts are in place.

In my original post, I described it as the rear motor mount. We are talking about the same mount. The bolt to cut is on the firewall but doesn't go into the rear motor mount, per the corksport directions, but is in the way of getting a socket onto one of the nuts on the rear motor mount.

I'll see if I can get wrenches to reach the bolt and nut that hinges the two motor mount pieces. If I can't even get leverage, then, I'll come in through the top as in the corksport directions, yours and lostmybook directions. I got a Dremel tool and cutting wheels so if need be, I'll be able to cut that bolt under the wiring harness.

 

[Installshield 2]

oh ok...yeah, as i mentioned, it gets tough with which mount is which because the engine is side ways...most shops will still refer to the 'front' and 'rear' mounts as the timing belt and flywheel side mounts...which are 'left' and 'right' in a FWD...thats all, i was just confused.

anyway, yeah leave the top of the mount alone, sling the engine with a chain and appropriate adjustable bar (you can rent them pretty cheap, most stores call them an 'engine leveler')...loosen the other mounts slightly...pull the through bolt out of the firewall mount, tilt the engine up and forward slightly (should give you enough room), install the inserts...retorque everything down...and you're done...thats most likely a hell of a lot easier than pulling the entire rear mount out.

 

[rit14623]

I got my motor mounts. It came with a free sticker, instructions print out, and warranty.

Here's another picture with the items out of the bag.

Here's another picture. The end of one motor mount has an indentation and the opposite one has a molded shape to fit into the indentation.

 

[616Nickel]

I ended up doing what you suggest in the OP--I followed all the instructions to get access to the motor mount nuts, without too much trouble. But the nuts were a huge pain: I managed to remove two of the three nuts, but the socket slipped on the rear passenger side nut badly enough to start rounding off the edges of the hex. The nuts are thin and on a long stud, and that along with the metal hydraulic lines running along the firewall made it very difficult to get a socket properly seated on that particular nut. Plus, the nuts are amazingly tight--the other two came loose with a loud bang that made me think I'd broken a socket extension.

So I went underneath the car and removed the bracket that connects the mount to the transmission, while supporting the engine with a jack. After removing the bracket, I had decent access to the mount, which was badly torn. I just sprayed brake cleaner on the mount, then filled the gaps with fast-curing urethane (as I'd done for the front and passenger-side mounts). It was a little clumsy poking the caulking gun up into the mount, but it seemed to do the job OK. Left it overnight, reinstalled the bracket, and voila. Done.

I'd like to replace the mount altogether some time, but I have no idea how I'm going to get that nut off. Might be best just to take it to the garage and pay them to remove it, then replace the mount myself.

TLDR: Your idea about going in from the bottom and removing the bracket will work fine, and may cause a lot less grief.

 

[rit14623]

I didn't have enough time to do both motor mounts in the Protege5, but I did get to install the inserts in the front one this weekend.

From the time I posted this to yesterday, the front motor mount got torn. Ironic or a coincedence. One rubber end was torn and was sunk down. To answer my own question, the motor mount inserts can be used in a motor mount that is torn. The inserts go in tightly and the edges of the inserts mate up with the metal and rubber of the motor mount thus repositioning the motor mount center hole back to the middle. The two sides of the motor mount are not exactly the same, one has a small rubber tab that does nothing I guess except to indicate it should be pointing to the driver's side, and so the two motor mount inserts are not exactly the same. You can't install them on the wrong side. The hardest part was getting the rusted nuts off. Reinstallation of the motor mount was exponentially faster.
I used my floor jack to raise the engine up. When I put the motor mount bolt back through, it wasn't quite aligned so I used a pry bar. I put it in between the engine and the cross member and was able to lever the engine a bit higher to push the bolt all the way through.

Now, the engine shakes the car a bit at idle when parked in P or stopped at a stop light in D. While driving, the shaking isn't that noticeable.
Anyways, I didn't get to take photos while doing all this.

 

[rit14623]

I spent a couple of hours trying to work on the rear motor mount. I couldn't get the bolt/nut that goes through the rubber section loose. I tried to cut it with a Dremel tool. Got about 1/3 of the nut cut up but had to stop when I ran out of daylight. There's not a lot of room underneath and going in from the top would require removing the intake manifold. I had a 1/2" breaker bar but I couldn't get it in a position to spin the nut. I have a 1/2" ratchet but I couldn't get leverage to break it free.
So, I'll be working on it next weekend. I don't see that nut/bolt coming loose while driving, it would be a Christmas miracle.

 

[Installshield 2]

I ended up doing what you suggest in the OP--I followed all the instructions to get access to the motor mount nuts, without too much trouble. But the nuts were a huge pain: I managed to remove two of the three nuts, but the socket slipped on the rear passenger side nut badly enough to start rounding off the edges of the hex. The nuts are thin and on a long stud, and that along with the metal hydraulic lines running along the firewall made it very difficult to get a socket properly seated on that particular nut. Plus, the nuts are amazingly tight--the other two came loose with a loud bang that made me think I'd broken a socket extension.

So I went underneath the car and removed the bracket that connects the mount to the transmission, while supporting the engine with a jack. After removing the bracket, I had decent access to the mount, which was badly torn. I just sprayed brake cleaner on the mount, then filled the gaps with fast-curing urethane (as I'd done for the front and passenger-side mounts). It was a little clumsy poking the caulking gun up into the mount, but it seemed to do the job OK. Left it overnight, reinstalled the bracket, and voila. Done.

I'd like to replace the mount altogether some time, but I have no idea how I'm going to get that nut off. Might be best just to take it to the garage and pay them to remove it, then replace the mount myself.

TLDR: Your idea about going in from the bottom and removing the bracket will work fine, and may cause a lot less grief.

what you probably need is a stripped nut/bolt remover like craftsman 'easy outs'...They come in different sizes, as well as depths (you can get some that mimic a deep socket)...they just have 'teeth' inside that will bite onto the stripped nut, and remove it easily...just remember the nut will be completely useless after you use these...

The studs are probably too long to get a normal sized easy out on there, so you'll need the deeper variety, and just hope there is room to get a socket on top of it...but yeah, you may have to remove the intake manifold to get it seated properly anyway...

Also, something like PB blaster is your friend with this. You mentioned a loud crack when you broke the others loose, so its a clear sign you either were not using any penetrating spray, or a type that wasn't penetrating haha. I'm not a salesman, but i've gone through nearly every brand of spray you can regularly find...and PB blaster is a night and day difference to most of them. I haven't attempted any work on my P5 in the last few years without at least one bottle of that, and haven't stripped and/or gotten completely stuck yet...knock on wood, though.

 

[616Nickel]

what you probably need is a stripped nut/bolt remover like craftsman 'easy outs'...They come in different sizes, as well as depths (you can get some that mimic a deep socket)...they just have 'teeth' inside that will bite onto the stripped nut, and remove it easily...just remember the nut will be completely useless after you use these...

The studs are probably too long to get a normal sized easy out on there, so you'll need the deeper variety, and just hope there is room to get a socket on top of it...but yeah, you may have to remove the intake manifold to get it seated properly anyway...

Also, something like PB blaster is your friend with this. You mentioned a loud crack when you broke the others loose, so its a clear sign you either were not using any penetrating spray, or a type that wasn't penetrating haha. I'm not a salesman, but i've gone through nearly every brand of spray you can regularly find...and PB blaster is a night and day difference to most of them. I haven't attempted any work on my P5 in the last few years without at least one bottle of that, and haven't stripped and/or gotten completely stuck yet...knock on wood, though.

Thanks. I have a set of the Irwin bolt extractors, but weirdly enough, they don't have the 17 mm size, and the 11/16" size is just a little too big to grip onto the nut. Plus, as you point out, they're too shallow for the long studs on this mount. I'll have to go to Sears to see if they have a deep-socket 17 mm extractor, I guess.

I did soak the studs in penetrant, but no, not PB. I'll try that next time.

 

[616Nickel]

I spent a couple of hours trying to work on the rear motor mount. I couldn't get the bolt/nut that goes through the rubber section loose. I tried to cut it with a Dremel tool. Got about 1/3 of the nut cut up but had to stop when I ran out of daylight. There's not a lot of room underneath and going in from the top would require removing the intake manifold. I had a 1/2" breaker bar but I couldn't get it in a position to spin the nut. I have a 1/2" ratchet but I couldn't get leverage to break it free.
So, I'll be working on it next weekend. I don't see that nut/bolt coming loose while driving, it would be a Christmas miracle.

My first question was going to be whether you supported the engine, but I see you did do that. I recall that the through-bolt was quite tight inside the metal sleeve at the center of the mount, and I needed to tap and pry it to get it out, but then I live in a relatively low-rust environment. I made sure it was well-greased before I reinstalled it, though!

But you should still be able to go at it from both top and bottom (you removed the EGR, right?). I placed a socket wrench on the driver-side end from the top, and let it prop itself against the firewall while I worked on the passenger-side from underneath.

 

[rit14623]

My first question was going to be whether you supported the engine, but I see you did do that. I recall that the through-bolt was quite tight inside the metal sleeve at the center of the mount, and I needed to tap and pry it to get it out, but then I live in a relatively low-rust environment. I made sure it was well-greased before I reinstalled it, though!

But you should still be able to go at it from both top and bottom (you removed the EGR, right?). I placed a socket wrench on the driver-side end from the top, and let it prop itself against the firewall while I worked on the passenger-side from underneath.

Oh yeah, I've already worked on the front motor mount so I was aware that the engine/trans needed to be jacked.
The nut is partially cut up so I need to keep on cutting it up. I'm going to replace the bolt and nut. I actually used a torch on the front motor mount nuts to break them free and that worked. I didn't think that was a good idea for the rear motor mount.
I could get a wrench on the driver's side nut from below so I didn't think I needed to go in from the top.

 

[c4racer]

I broke a bunch of 1/2" tools trying to break loose the bolt on the rear motor mount from the top side.

I think you are much better off dropping the front suspension cradle to gain some space and attack it from underneath.

Use a liberal amount of WD40 or liquid wrench. And use 3/4" sockets. I broke a few 1/2" sockets in half trying to get that thing loose.

It's a major b**** of a job - one of the hardest things I've ever run across and I have built race cars and hot rods from the ground up.

 

[rit14623]

Well, I got the rear motor mount inserts installed.
And the pictures to show it.

I used my Dremel tool again to finish it off. I bought some reinforced cutting discs. Here's a picture of the cut up bolt and nut. I cut a bit into the bracket so I spray painted it later to prevent rust.
From underneath.

And removed

Here's another view from below. I had to remove the cross-brace underneath, which is held in by four 17mm bolts, to get leverage to remove the three bolts that hold the bracket to the transmission.

Here are pictures from below the car after the bracket was removed.

Here's pictures again of the rear motor mount inserts. The one with the square hole goes on the right side. Pretty easy to figure out.
The right side went in without problems but the left side would not fully go in. I tried multiple things to get it pushed in. I ended up cutting 1/8" off the insert of the left insert that goes through the rubber bushing and that worked. So, the bushings don't touch but they don't really need to.

Here's pictures of the inserts installed.

 

[rit14623]

Other notes: the rear motor mount wasn't torn. It shakes pretty hard when I start the car up. This didn't happen with just the front motor mount inserts.
It shakes harder while stopped and engaged in Drive. I slip it into Neutral to stop the heavy vibration.
The car doesn't jolt when I floor it, but I do feel like there's a bit less lag.
With the insert installed. I was still able to wiggle the bracket but was not able to swing the bracket to the same extent without them.

I don't have a close up of the bolt that I cut up, but there was corrosion within the nut and bolt, not just the outer edges.

 

[rit14623]

Here's the other half of the cut up nut. There's not a lot of space and I attacked it from the various angles that I could.

 

[616Nickel]

So this is my situation: I've replaced two of the three nuts, but the third one is completely rounded off (see inset):



As described above, I managed to fill the mount with fast-curing urethane from underneath the car, but it looks like my kludge didn't quite take, since I can see new cracks in the mount.

The main cause of this disaster is a) My incompetence, and b) That hydraulic junction at the top of the picture which prevents you from getting a socket onto the nut in a straight line from above (not a problem with the other two nuts). I have u-joints, but I think the worst damage was done on the first try, and nothing since then has been able to get a good hold on the nut.

So, any suggestions? I'm thinking of just taking it to a shop, but I'm not sure what they'd do to get it off. All the regular solutions (propane torch, vise-grips, Dremel) won't work because you can't get decent access, even with the battery and all the air intake removed up to the throttle body. I'm pretty sure I won't be able to get a nut-splitter in there. And I'm really reluctant to take off the intake manifold, because I've never done it before, and I'm not sure how to deal with all the coolant lines, etc.

By the way, the replacement nuts are 18mm, which is why they look so much larger than the old nut (17mm, rounded down to 16.5 or so).