Engine Mount & Cornering/Handling
 

After wondering about my engine mount on my 2001 Box for a while now, I decided to change the mounts anyway....... Car is 10 yr old but only 53k km (33k miles).

AND, it turns out that the rubber in mounts were cracked about 3/4 of the way. Mine's a tip box, so the only symptoms were a little vibration during idle and inital acceleration.

THE RESULT - less vibration during idle and but alot less during initial acceleration BUT suddenly the car feels very tight going around corners and feels sharp... Feels very confident in going around corners and during hard braking (this is an area which the car imparts very little confidence in the past). I guess in the past, having a big weight (engine) moving around didn't help !

What a difference..... I wouldn't have expected the cracked engine mount to have such an effect...

Wonder if the tranny mounts are worth changing next ?! Ha Ha... But it looks like alot of work to change those (at least on a tip box).

Did you do the engine mount yourself? How hard was it on a 1-10 scale?

I think the heat generated in the engine bay plays a role in the front mount deterioration. As for "how hard" , if you have good patience, it's not too bad. There are a couple nuts that can be a challenge, especially if the entire bolt shaft turns with the nut rather than the nut breaking free. I HIGHLY recommend, looking in the Bentley manual and marking the mount with a permanent marker for direction and placement. The mount can be reassembled wrong, (yeah I proved this the hard way and made the job two hours longer) oops.

ouch.. good to know. I'll definitely mark it! I'm assuming you did this without a lift? the only part that has kept me from doing this so far is the "lowering the engine" requirement. maybe i'm scarred from the 914 :)

I'm thinking i should be ok if I have the rear on ramps. I can then use my only floor jack for the engine part. where did you end up buying your mount from?

I thought this job was relatively easy, but I have a good selection of flex sockets, extensions, ratcheting wrenches, etc. access wasn't a problem. I used Pedro's DIY, which has excellent instructions and pictures. I always go to Pedro's site first as I think he has the best tutorials.

The studs usually come out with the nuts, which is no problem as long as you don't put them back in that way. You need to separate them and put the studs back in with 48 ft-lbs torque, and then install the nuts with 34 ft-lbs, otherwise they can apparently come loose. Not all DIY's make this clear.

Lowering the engine is no big deal. I used a scissor jack with a block of wood on top of it, lowered it until the engine hung free, and cranked the jack back up a couple of turns just so it was supported. I put the car, all four corners, up on jack stands to do the job - gave me about 17" clearance under the car, which was more than adequate.

I found the same surprising difference in how smooth and tight the car handled afterwards.

My thoughts on hydraulic jacks - they are for lifting only. I would never trust one to support something heavy without a jack stand or other mechanical support for any length of time.

My dad had a shop for 42 years, don't trust any jacks, always use multiple stands, one of our friends had a jack drop on his chest at his shop, he was lucky to survive it. As for lowering the engine, remember it's still connected on the drive end and you are not really lowering it much at all.

Thanks for the info on the Tip cars. Maybe I should do mine.

My tranny mounts were perfectly fine when I changed the front motor mount at 90,000 miles. I don't think that the tranny mounts wear as readily as the front motor mount.

thstone, thanks for the feedback. I think I will leave the tranny mounts alone for now...

As for the engine mounts, I had my mechanic change that and he made it look so easy.

Just in case anyone is wants to know... there is actually a Lemfoerder bearing that u can buy, it's less than $40 or so. So instead of buying the entire new engine mount, u can just replace the round bearing part. It's an updated 987 style as well and is similar to the standard mounts and NOT the harder race type. I didn't try that, as my mechanic didn't have a machine press at his workshop, so I went for the complete engine mount.

Stateofidleness - I got my engine mount from Pelican, they sell the complete engine mount as well as the Lemfoerder bearing.

Dale_K - just a side track - what ATF fluid are you on ? The original stuff only comes in 20 litre pak.

Shlim - I changed mine recently and it was starting to crack on two sides. Maybe all in my head but the car does feel tighter.

stateofidleness - I changed mine at the same time I did the water pump and drained the coolant. It seemed to make it much easier since the coolant pipes are out of the way. I have to hand to folks that change it out while the pipes are in place. It took me some time but wasn't very 'hard', I'd say a 3 out of 10. There are some nuts that are hard to reach but the right tools will help. It can be confusing putting it back together, I took a picture while it was on my bench so it was a snap to put back together.

Maybe it's just me but mine was completely loose, i.e. rubber was completely cracked all the way through, but I didn't notice any difference in handling or shifting after replacement. I was hoping for crisper shifting. The only difference is that it stopped making that thunk noise while shifting under heavy acceleration. Thought about getting Pedro's, but was scared away by the reports of vibration (due to the less resilent rubber) and ended up getting the (improved) OEM mount from Sunset for $110. Took about 6 hours to change (I know, it's probably a 2 hr. job in the shop, but I'm not very handy when it comes to working on cars, I only tackled this myself out of necessity, i.e., I'm cheap, make that frugal). Not too difficult, just a lot of things to remove and very tight working area. The most time consuming part was getting the car on the jack stands. If you jack your car up at the specified jacking location, where do you put the jack stands?

" If you jack your car up at the specified jacking location, where do you put the jack stands?"

I start by lifting from the rear jacking point, which will raise the front enough to get a jack stand in there. Then I do the same thing on the other side. Once the front is raised I lift the entire rear by lifting from the suspension mounting point and put both rear stands in place.

Do a forum search - you'll find a few different methods people use and then pick the one you like best. Also, there's a write-up in Pelican's technical section which describes another way to do this. Look here:

Pelican Technical Article: Jacking Up and Lifting the Boxster on Jack Stands - 986 / 987

Here's the part number on Pelican: 987-375-023-05-M100
Is this the "revised" 987 version? Are there any differences in re-installation with a new mount? (dumb question: this is the "front mount" right, closest to driver right?)

Mount is the same physically, changes include a redesign to the rubber isolator, and the reduction of weight by cutting triangles here and there in the framing.

Also, the new mount has four mounting points on the engine side, as opposed to the earlier models which only have three. You can only take advantage of this fourth mounting point if you have the newer style oil pump housing cover on the engine. If you don't I wouldn't worry about it as I don't think it is worth the trouble and expense to change it.