# Ah crap, motor mount busted!



## DanB (Feb 20, 2002)

So about a week ago I start my car and I can feel this vibration in the floorboard directly below my feet at about 1200-1500 RPM. After driving a bit and feeling the same vibrations throughout the chassis of the car, I've come to the conclusion that one (or both, but likely just one) of my motor mounts has busted. The car has 60K miles on it, has been supercharged for 40K or so miles, so it's likely that the fluid filled driver's side (as suggested by DanT) has busted open. I've ordered two new motor mounts and tranny mounts (just to be safe) at the tune of $65/motor mount and $8/tranny mount, and I'm going to see if I can get Shane to put them in (He's a BMW tech and has access to that cherry picker engine hoist thing). 

*sigh*

Can anyone tell me, is it unsafe to drive my car around until this is fixed? Will I put dangerous stress on components of my drivetrain? I drove on my Volvo's busted motor mounts for about a year, but the engine probably weighed 1/3 of the 4.4L V8. 

-DanB


----------



## DZeckhausen (Mar 11, 2003)

DanB said:


> *I've ordered two new motor mounts and tranny mounts (just to be safe) at the tune of $65/motor mount and $8/tranny mount, and I'm going to see if I can get Shane to put them in *


 You should install the Rogue high performance tranny mounts rather than another set of those squishy, hourglass shaped BMW tranny mounts.

Replace:









with:









And I assume we are talking about a DIFFERENT Shane and not SS!! :yikes:


----------



## DanB (Feb 20, 2002)

Are those tranny mounts for an AT? If so, how much are they and what are their advantages? 

Shane's a local BMW mechanic here in SD. SS? HAHAHA! I bet he doesn't even change his own oil! (Do ya Shane??) :rofl:


----------



## DZeckhausen (Mar 11, 2003)

DanB said:


> *Are those tranny mounts for an AT? If so, how much are they and what are their advantages?
> 
> Shane's a local BMW mechanic here in SD. SS? HAHAHA! I bet he doesn't even change his own oil! (Do ya Shane??) :rofl: *


 They are $45/pair (including new hardware). They much stiffer than stock, yet don't seem to transmit any more noise than the factory mounts.

For the 6-speed folks, they crisp up the shifting. I would imagine it should help the automatic as well, since there will be less twisting of the power train, although the effect will probably be more subtle. Might even help your new engine mounts last longer.


----------



## DanB (Feb 20, 2002)

Hmmm. Hey Dave, how hard is it to throw new tranny mounts in? I might just have to get some from you. ;-P

-DanB


----------



## DZeckhausen (Mar 11, 2003)

DanB said:


> *Hmmm. Hey Dave, how hard is it to throw new tranny mounts in? I might just have to get some from you. ;-P*


 If your car is on jackstands, simply move the floor jack under the car and support the tranny just forward of the drain plug. Remove the 6 bolts holding the aluminum cross brace in place. You may have to bend two heat shields, but they are like aluminum pie plates and will bend back easily. Remove the two nuts at the top of the stock tranny mounts. Yank off the 4 spring clips that hold the O2 sensor harness to the cross brace. Lower the cross brace and remove to a convienient work bench. Remove the two remaining nuts on the tranny mounts and install new ones using provided hardware. Match the dimple in the tranny mounts with the raised bump on the cross brace. Re-install brace and reattach O2 harness.

Done! With a lift it's a 25 minute job. Without a lift, it's closer to 45 minutes, assuming it's your first one. Subsequent swaps get faster.


----------



## SS (Dec 20, 2001)

DanB said:


> *Are those tranny mounts for an AT? If so, how much are they and what are their advantages?
> 
> Shane's a local BMW mechanic here in SD. SS? HAHAHA! I bet he doesn't even change his own oil! (Do ya Shane??) :rofl: *


LOLOLOLOLOL...I knew which Shane you were referring to, becuase I've seen your posts about him before. Actually, as far as working on cars - I've been doing that since a young buck! My dad, all my brothers, and even some of my sisters know how to do at least SOME work on cars (with my father & my oldest brother doing as much as changing engines/trannies, modifying engines, etc.).

So, yes, I actually do change my own oil, and most major things on my cars. Well, on the E39, BMW covered everything, and now my extended warranty company does. However, with my older BMW and the Lexus, I performed ALL maintenance work and difficult repairs myself (Whew, as well as be the guy everyone else calls when they want their car fixed  ) 

Hehe...I may stay well-dressed, but I'm never afraid to put on the sweats and get dirty while working on a car!

That said, I think DaveZ will be doing my brakes for me...first time for everything I guess.

Surprised?


----------



## Ågent99 (Jan 7, 2002)

Dan,

I have these tranny mounts from Dave...I just need to install the biotches.... 

Hey, what are your summer plans this year? Can you make it to the CDV clinic at all? Gonna visit the homeland any time soon?

Chris :guitar:


----------



## DZeckhausen (Mar 11, 2003)

Ågent99 said:


> *I have these tranny mounts from Dave...I just need to install the biotches *


 So what will you use to hold your bathroom door open?


----------



## rsmillar (Feb 14, 2003)

*DanB you are SUCH a putz!!!*

Come out to my house, I'll do the tranny mounts for you in an hour. And I'll even swap in my CAI for that filthy little hairdryer you have at the same time...

Re: driving your car with broken motor mounts. I'd be surprised if they (or even 1) really are broken. But if the one on the driver's side *is* broken, then you are at increased risk for such things as:

fan blades interfering with fan shroud and grenading the fan,

radiator nipples breaking due to increased movement of the rad hoses,

general increased stress on the remaining mounts,

etc. etc.

Picture your motor being held at two points instead of three, with the missing point being the most important one - the one that acts against the torque exerted by the motor on the drivetrain.

One question I have for you though - is the vibration you're feeling only when the motor is driving, or does it also occur when in park/neutral? Also, do you hear any funny noises during hard shifts? (ok, that's two questions).

Here's a quick test:
1. Park car in open area, open hood, start motor.

2. Get a friend to stand to the side of the car, next to the driver's front fender.

3. PLANT your left foot on the brake and put your car in drive.

4. Rev the motor quickly to ~1500 rpm and release the throttle while your observer notes any movement in the motor - there should be very little torque-movement.


----------



## Ågent99 (Jan 7, 2002)

DZeckhausen said:


> *So what will you use to hold your bathroom door open?  *




Actually, I am using the box they came in...err...are *still* in...as a door_stop_. You know, to keep the doorknob from punching a hole in the new drywall. :yikes:

Chris :eeps:


----------



## Ågent99 (Jan 7, 2002)

*Re: DanB you are SUCH a putz!!!*



rsmillar said:


> *Come out to my house, I'll do the tranny mounts for you in an hour. And I'll even swap in my CAI for that filthy little hairdryer you have at the same time...*


Hey, if you can do ALL THAT in an hour, well then I :bow: and :clap: to you!

:spank: DanB for such thoughts of driving with a busted mount! I mean, HELLO :stickpoke

Chris :gay:


----------



## DKSF (Apr 4, 2003)

Hey Dan, I totally forgot, but I was talking shop with one of the techs at Phaedrus BMW in SF a while back and he mentioned that they had a customer's car come in the an SC where the motor mount broke recently. He said that the engine torqued and the engine "tipped over" and slammed the blower into the fender. 

I have no idea if it was true or not, :dunno: , but his point was that the motor mounts could fail with the addition of the SC.

Again, have no idea how true this was, but that's what he told me.


----------



## rsmillar (Feb 14, 2003)

That's a good point - I hadn't considered the possibility of the blower coming into contact with the fender.

I had a very powerful motor in an old musclecar which was forever breaking motor mounts. The obvious solution was to install a solid mount, but they transmit noise/vibration directly to the frame and make the car very annoying to drive.

The solution I found was at the local marine hardware store. I picked up a large stainless steel turnbuckle (back then it cost me about $100) which had an adjustable range from about 10-15 inches. I bolted one side of this to the engine block, and used a short piece of large-qauge chain to attach the other side to the front crossmember. I adusted the turnbuckle such that the only time it was being "used" was under torque, meaning nothing got transmitted through it during normal driving. I never broke another mount.

On an E39, you need to CAREFULLY consider where you would attach such a system to the block, since you wouldn't want to rip a chunk of it out. But I'm sure with a little thought and engineering, a solution is easily had.


----------



## DanB (Feb 20, 2002)

DKSF, you're scaring the hell out of me! :behead:


Randy, I'll take you up on that. But tell me, How are you gonna hoist the engine up??? I dun wanna use your ******* "wood on a floorjack" trick or whatever you use on a '67 cuda.  (seriously, thanks for the offer). The vibration is felt both at idle in park and in gear. The car has also started to shift a bit harder. 


Chris, planning a little road trip on the 20th of June for a week. Will be going up north, reno, vegas, AZ, and back home. I'll let you know when plans are solidified and maybe we can grab some dinner or something (or maybe you can tag along to vega$!). 

Dave, I'll let you know about the mounts as soon as I get approval from the boss. If Randy does this for me (I'm not putting out this time millar) I should have enough $ to get those mounts from you. 

Thanks guys. I'll be peddling around in Amy's taurus for the next few days...

-DanB


----------



## rsmillar (Feb 14, 2003)

'67 Cuda? Nice try, boy. That's a car YOU would look good in.

Lots of ways to raise the engine/trans. A shop will simply use a trans jack on the oilpan with the car up on the lift. You can do the same thing: knowing you, you'll drive the car up on a curb so one side is on the grass, other side is on the street, then use your trusty BMW jack to raise the motor. Make sure you bring a knife with you under there so you can hack your arm off like that poor SOB in CO...


----------



## DanB (Feb 20, 2002)

Hey, I did that engine rev under load thing... I'd say it dodges to the right a good 5 degrees when I rev it in D, and a little bit when I rev it in P... So methinks mounts???


----------



## vietsb (Apr 8, 2003)

When the ESS tech replaced my passenger-side motor mount (it's part of the SC bracketing) they did so w/o an engine lift. They simply placed a piece of wood under the lip of the oil pan and gently jacked it up. When we did Riverflyer's install, the tech did the same thing. Not sure this is actually safe, but it worked!:dunno:


----------



## Ågent99 (Jan 7, 2002)

Like, major wood, dude! 

That pic looks like it's a piece of MDF...not really "wood" per se....

Chris :eeps:


----------



## vietsb (Apr 8, 2003)

:liar: :bs: :wahwah: :asshole:


----------



## Ågent99 (Jan 7, 2002)

:fingers:

Chris


----------



## DanB (Feb 20, 2002)

Ågent99 said:


> *Like, major wood, dude!
> 
> That pic looks like it's a piece of MDF...not really "wood" per se....
> 
> Chris :eeps: *


So what you're saying is that Viet's car was being jacked up by no more than mulched up wood and glue?

:eeps:

-DanB


----------



## vietsb (Apr 8, 2003)

Don't forget the *formaldehyde*. Mmmmm, smells good!

Dan, I'm e-mailing ya something.


----------

