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DISCUSSION => Engine + Driveline => Topic started by: 76m2002 on May 03, 2012, 09:45:20 AM

Title: How do stock motor mounts fail?
Post by: 76m2002 on May 03, 2012, 09:45:20 AM

Our '91 318is seems to have a lot more rpm-related chassis vibration than before, it feels similar to when I put urethane motor mounts in another car.  Can motor mounts stiffen up with age, rather than breaking?  There is no engine rock visible.

Title: How do stock motor mounts fail?
Post by: Geoff on May 03, 2012, 11:35:34 AM

the stock motor mounts are hydraulic.   I dont know for sure, but I  would guess that when they go bad,  the cushion effect is no longer working and the mounts are reduced to just banging up and down with the engine.
                                                                            Geoff

Title: How do stock motor mounts fail?
Post by: thedguy on May 06, 2012, 07:27:59 PM

They tear and cause the fluid to come out.  The engine moves more and is most noticeable by bucking or harsh driveline lash when getting on and off throttle.

I replaced mine with some at rock auto and was well worth it.

Title: How do stock motor mounts fail?
Post by: PeabnutBubber on May 26, 2012, 04:14:38 PM

Interesting, I've felt a lot of movement coming from the engine and such and I never thought to check the mounts. Would I be able to notice the decay by looking at them?