Curious about failed engine mounts

[itzbob46]

I often read forum topics regarding replacing failed engine mounts. Now I'm curious, what are the symptoms of a failed mount?? What problems occur when a mount is failed or just weakened?

Thanks, Bob

[pk2]

Once I knew, but have forgot the nuances. I do know you can't see the actual part that counts without taking it out. If no-one pipes in you can contact Pedro at Pepdros garage in Florida. He would be happy to tell you...he makes reproductions (find him on Porsche Pete's Boxster board or google it

PK

[Orient Express]

Look for a dark purple or green stain on the bottom and sides side of the mount. That is the fluid that is leaking out of the failed mount. If there is no stain, then the mount has not failed.

[itzbob46]

Look for a dark purple or green stain on the bottom and sides side of the mount. That is the fluid that is leaking out of the failed mount. If there is no stain, then the mount has not failed.

But what happens to the car's performance when the mount fails?

I recall that I had a Maxima once with motorized engine mounts that actually counteracted the torque of the engine. They were problems and would burn up. Once failed, I could not tell the difference in the way the car peroformed!!!!! It just smelled like burned rubber! Luckily the car was under warrantee. I know that the Boxster is a different animal, but now that I know there is liquid inside it, it does sound like a problem waiting to happen.......

Bob

[soopster]

Symptoms that I have heard from a failed engine mount include: vibration particularily around 3000 RPM when decelerating, trouble shifting in manual transmissions and a clunk as engine moves upon shifting/turning.

When I let off the gas and the car goes through 3000 RPM I get a low vibration from behind me. I also have a notchy feeling when trying to shift, especially between 1st to 2nd, it can stick significantly but not always. I will be replacing the engine mount in September, so will let everyone know if those two problems get better.

I could be wrong but from what I've researched my understanding is that the Boxster engine mount is not hydraulic (ie. no liquid, oil etc). The two transmission mounts are hydraulic though. The engine mount looks to be simply rubber. Pedro has a version that is filled with a resin around the rubber that people seem to like better for the track but does generate more vibration. I will be going for the stock part since my racing is restricted to getting to the coffee shop in the morning on the way to work.

Edited August 31, 2009 by soopster

[itzbob46]

When I let off the gas and the car goes through 3000 RPM I get a low vibration from behind me. I also have a notchy feeling when trying to shift, especially between 1st to 2nd, it can stick significantly but not always. I will be replacing the engine mount in September, so will let everyone know if those two problems get better.

This is precicely what I would have said!!!!!!! Are you driving MY car??

Mine really does not stick on the shift, but first to second feels really newbie unless the RPM is over 4K. The vibration is on occasion but is a scarey feeling. The clutch engagement is kinda rough when the car is cold, but I've attributed that to the surfaces perhaps working better when hot (maybe??).!.!.

But now the original question remains. What's normal and what are symptoms of a bad engine mount (or transmission mount). Need input form drivers who have been there/donw that.

Bob

[soopster]

Take a look at Pedro's article on replacing the engine mount. Describes the symptoms as well. Pretty much what I am feeling and what I outlined above.

http://www.pedrosgarage.com/Site_3/Install...gine_Mount.html