Boxster Engine Mount Replacement

[BoxsterRS]

I have a 98 Boxster, that the engine mount seems to be broken. I bought the bentley repair manual and it shows detailed intrsuctions on how to replace it. I want to get some forum member imputs that have done the actual replacement. I plan on doing the repair with my dad over the weekend. Is there anything that the manual doesn't cover, and will I need to jack the engine ? I really am going to follow the instructions but if anyone outhere has done it and has some tips I'd gladly appreciate it. My question to jacking the engine is becuase I don't have the repair manual with me and want to clear that from my mind.

[por911]

Its not too bad of a job, just replaced one a couple months ago. I found it easier to put the rear of the car up onto a set of rhino ramps. Then, put a floor jack (with a pad)right at the point where the engine and trans come together. This will give you lots of support without getting in the way. You'll find the mount needs to be taken out as an assembly with the bracket to the chassis. The center bolt comes out easily with the assembly out of the car. There are some upper nuts/bolts on the mount to engine which you might need to accces through the panel behind the seats. Sorry I don't have pics, on our other computer(not near it).

You can support the engine from up top but most people don't have the engine/trans suppport bar. An Autozone might have one around you but if your not careful it quite easy to damage the gutters that it rests on. :cheers:

[BoxsterRS]

Its not too bad of a job, just replaced one a couple months ago. I found it easier to put the rear of the car up onto a set of rhino ramps. Then, put a floor jack (with a pad)right at the point where the engine and trans come together. This will give you lots of support without getting in the way. You'll find the mount needs to be taken out as an assembly with the bracket to the chassis. The center bolt comes out easily with the assembly out of the car. There are some upper nuts/bolts on the mount to engine which you might need to accces through the panel behind the seats. Sorry I don't have pics, on our other computer(not near it).

You can support the engine from up top but most people don't have the engine/trans suppport bar. An Autozone might have one around you but if your not careful it quite easy to damage the gutters that it rests on. :cheers:

Thanks, I'll keep that in mind. Very helpfull

[mikefocke]

How to with pictures

http://www.ppbb.com/boards/ppbbphp/showfla...rue#Post1106222

[farmboy]

Hey that how to looks great.

I suspect my mount is blown (I have a rumble on turns to the left) and over bumpy roads. How do I know for certain if it's my mount that's blown or a rear arm? I have about 70k miles.

Thanks!

[Tool Pants]

You have to get under the car and look at the condition of the mount. The mount was a problem area on the early cars and Porsche changed the design. If there is a problem with the mount then the engine can touch the frame and you will get a vibration, usually when making turns.

Sometimes the rubber bushing falls apart. Other times part of the bushing can slide out of the mount. In the pic below you can see it has slid out a bit. In that case you can pound it back in then put a screw in the housing to keep it from sliding again.

Trivia. That rubber bushing is also use on the 996 transmission. But Porsche does not sell just the bushing. The mechanics tell me there is an aftermarket source for just the bushing.

[986Jim]

One of the things I have always done with many cars is pull the mounts and fill the empty spots in them with urethane.

This was filled with Devon Flexane 94 on my dad's race car. It doens't make them solid or so they will vibrate at all. The stock rubber is still in there, this is just poured urethane around it to fill in the gaps. We filled all 5 mounts on his engine and he has pretty lumpy cams and its still smooth, but it stops the engine from jerking around in the bay a lot. Even on the dyno the motor doesn't move much. These are on a VQ35DE powered 4th Gen Maxima. Puts 269whp N/A and 390ish on Nitrous to the wheels.

You tape up the back side and pour the Flexane in and it sets over night then re-install the mount. It will pretty well solve the motor moving around problem or mounts rubber wearing out. Pretty slck stuff.

You'll have to search around to find it, but these guys carry it.

http://www.venselenterprises.com/onlinecat...plies/p305.html

Edited August 4, 2006 by 986Jim

[Stefan]

Sergio,

The engine mount is pretty straightforward to do. I did it in my driveway. Here are some tips:

- Porsche recommends that the car be supported by its jacking points (not by its wheels) when removing the cross braces. That means that using a Rhino Ramp is not good. It could cause alignment issues because you're removing structural components that hold the suspension in place. I put my car on four jack stands under the four jacking points.

- The upper motor mount bolt is tight to get at. A socket won't fit. I recommend using a flat wrench (offset won't fit either). I believe the size is 15 mm but it should say in the instructions listed above.

- Have all of your torque specs available before you start. It will make your life easier.

- I strongly recommend using either a floor jack or a transmission/engine jack to jack up the engine. A bottle jack or X jack is not sufficient (or safe IMO).

- If a motor mount bolt is stubborn to go on or off, try jacking the engine slightly more or slightly less

- You may need a deep socket to remove the lower motor mount bolts

---

This is a very satisfying job to do because it seems like a big deal to disconnect the engine but it really is not very hard. It took me less than an hour and a half and I had never done it before.

Good luck!

[farmboy]

986jim-

so like this then? ;)

i had the bushing slide in the mount too (just like in toolpant's picture), so i hammered it flush, then appled a big 10mm bolt and nut through the thing before the flexane.

[LemmyCaution]

...

- Porsche recommends that the car be supported by its jacking points (not by its wheels) when removing the cross braces. That means that using a Rhino Ramp is not good. It could cause alignment issues because you're removing structural components that hold the suspension in place. I put my car on four jack stands under the four jacking points.

...

Thanks for the notes Stefan - Question:

Apparently - though I have not confirmed this - Porsche also recommends using an engine support bar (mounts between the gutters of the engine compartment access bay).

I'm not sure I would trust my abiliity to lower my floor jack slowly and accurately enough to drop the engine 1 inch. It tends to drop fairly quickly and I've seen recommendations against using a bottle jack.

Am I being paranoid? Suitable support bars are available for $75 or so from a number of sources.

Thoughts all?

[farmboy]

I had no problem using just my 2 1/2 ton floor jack under the engine. No special equipment necessary. I left the standard cup on the jack and lifted/lowered directly under the engine that was just in front of the oil pan. Obviously you'll want to jack near the front of the engine where the mount is, and this tends to get in the way a bit while you're working there. Don't forget you can break loose all the bolts before you bring the jack in! I'd highly recommend that strategy since it'll give you more room to work.

Contrary to the DIY listed here, I found that my mount only had three bolts. Maybe it's because I have a '98. Further, I found that the upper bolt was easier to access from the bottom not the top.

A 15mm deep socket would be beneficial for the long bolts that hold the mount up to the body.

BTW. The mount took several hours to remove, but went back in pretty quickly.

Here is a picture of my "new" mount...

[LemmyCaution]

I had no problem using just my 2 1/2 ton floor jack under the engine. No special equipment necessary. I left the standard cup on the jack and lifted/lowered directly under the engine that was just in front of the oil pan. Obviously you'll want to jack near the front of the engine where the mount is, and this tends to get in the way a bit while you're working there. Don't forget you can break loose all the bolts before you bring the jack in! I'd highly recommend that strategy since it'll give you more room to work.

I'm still on the fence about using the floor jack-

Did you open the access panel behind the seats to access the upper bolts?

Here is a picture of my "new" mount...

I'll be interested to hear how your repaired mount works. The original mounts look a little 'fragile' when you consder the forces that it needs to control.

[farmboy]

I'm still on the fence about using the floor jack-

Do what you feel comfortable with - you'll be under the thing. ;)

Did you open the access panel behind the seats to access the upper bolts?

I had removed the access panel anyway since I also did the serpentine belt. It wasn't really useful during the mount job, other than perhaps adding more light to the area while I was working.

I'll be interested to hear how your repaired mount works. The original mounts look a little 'fragile' when you consder the forces that it needs to control.

The repaired mount works wonderfully. I was considering a new mount, but then I started to think that since my main issue was that the insert slid, the same could happen again with a new mount. Seems like that's addressed by the new bolt I installed through the housing and the insert ring. There certainly won't be any cracking on the weak stock rubber either, since it's now solid! It's not very rough either, I used Flexane 80 instead of the harder stuff. Then again about 10 years ago I swapped engines on my track car and went with a solid metal mount. Nothing here could be that bad :)

[LemmyCaution]

:cheers:

After 2 weeks of procrastination and deliberation Wednesday evening, I finally took time to replace my engine mount and fuel filter.

There's a more complete post at PPBB.com - I posted it there as Craig's post is on PPBB.

The support bar was really helpful:

Placing the clamshell in service position was easy - The reverse was not as I was pretty brain-dead at this point. The extra time installing the bar was worth it in terms of safety and control. In my mind, jacks are for lifting and lowering only. The bar also

allowed greater control over the process of lowering the engine to remove the lower

bolts from the engine side of the mount.

Knowing what to expect makes it so much easier to work on this car. Thanks to this thread and especially Craig (WA)'s post on PPBB, Stefan, ToolPants etal for posting their experience here.

[LemmyCaution]

The repaired mount works wonderfully. I was considering a new mount, but then I started to think that since my main issue was that the insert slid, the same could happen again with a new mount. Seems like that's addressed by the new bolt I installed through the housing and the insert ring. There certainly won't be any cracking on the weak stock rubber either, since it's now solid! It's not very rough either, I used Flexane 80 instead of the harder stuff. Then again about 10 years ago I swapped engines on my track car and went with a solid metal mount. Nothing here could be that bad :)

I saved my old mount and will repair per your example - thanks for all the help and encouragement!

Edited October 9, 2006 by LemmyCaution

[LemmyCaution]

FYI - the part number for the 'clips' (the water intake and outlet hoses) that I mentioned is:

996-106-425-02 - $3.16 cents from Sunset.

As noted, the hose clips on my car were very brittle and broke when removed. For $3.00, they should be replaced along with engine mount or fuel filter.

[John V]

FYI - the part number for the 'clips' (the water intake and outlet hoses) that I mentioned is:

996-106-425-02 - $3.16 cents from Sunset.

As noted, the hose clips on my car were very brittle and broke when removed. For $3.00, they should be replaced along with engine mount or fuel filter.

Quick bump to this thread. I just did the motor mount on my '00 S. 40,522 miles and it was torn almost all the way around. The center aluminum portion was hanging on by just a thread of old rubber.

I was forced into using the factory Porsche mount because I use this car for competition and a urethaned mount would be illegal. However I purchased a replacement mount from a ppbb member and urethaned it. I cut away all the old rubber prior to doing this, because the center part had clearly moved off center - plus all the old rubber was deteriorated and dry-rotting. I didn't believe it when everyone said these mounts fail at a young age, but it seems to be true if the car is driven hard.

Definitely buy the clips that LemmyCaution suggests. I was as careful as I could be, and I still broke both of mine.

I'll post pictures up later of my turn mount and my urethaned mount which I'll hold onto as an emergency spare.

[mee]

As long as this thread is revived, are you using Flexane 94 which is a Shore A 97 hardness? That seems pretty darn hard to me. There is also a Flexane 80 which is 87A which still seems plenty hard to me. Any comments? Tire tread rubber is typically around 70A.

[insite]

As long as this thread is revived, are you using Flexane 94 which is a Shore A 97 hardness? That seems pretty darn hard to me. There is also a Flexane 80 which is 87A which still seems plenty hard to me. Any comments? Tire tread rubber is typically around 70A.

i used Flexane 80 to do mine. i notice a bit of extra vibration at idle and when decelerating past 2400 RPM. other than that, it's fine. the idle really is a bit more harsh. not sure how much worse the Flexane 94 would be. Once the 80 cured, it was pretty darned hard. FYI, i also filled my control arm trailing link bushings with Flexane 80 and baked them to cure. this made a MARKED difference in handling crispness.

[mee]

FYI, i also filled my control arm trailing link bushings with Flexane 80 and baked them to cure. this made a MARKED difference in handling crispness.

Cool! Thanks for the info. Is this what Porsche calls a "track rod" (#17 in PET) or what some others call a "tie rod"? Any pics? If it's the track rod, my guess is this would help maintain/promote toe in under load and aid stability. Wth a pound of this mix, you can probably do a heck of a lot.

[insite]

Cool! Thanks for the info. Is this what Porsche calls a "track rod" (#17 in PET) or what some others call a "tie rod"? Any pics? If it's the track rod, my guess is this would help maintain/promote toe in under load and aid stability. Wth a pound of this mix, you can probably do a heck of a lot.

here's a pic. i think mainly it helps maintain caster (and hence camber) through the corners. bottom line: it's more crisp.

[John V]

As long as this thread is revived, are you using Flexane 94 which is a Shore A 97 hardness? That seems pretty darn hard to me. There is also a Flexane 80 which is 87A which still seems plenty hard to me. Any comments? Tire tread rubber is typically around 70A.

I used the Flexane 80. It's more than hard enough to the touch. I will urethane the mount that just came out of my car as well... maybe trying a softer compound of urethane this time.

You ABSOLUTELY need to lift the motor. I used a floor jack. If you have a reliable floor jack that is easy to control, I would say to use it, but to have a jackstand or blocks under the motor just in case the jack fails. You need to support the motor to loosen all the bolts, and then lower the nose of the motor (towards the front of the car) slightly to allow the lower bolts to back out and the mount to come out. It takes some wrestling with the coolant hoses, but it will come out.

Here is the mount that came out of my car. Again this is a 2000 S with about 40,000 miles on it.

Edited March 12, 2007 by John V

[kedf1]

getting ready to redo my motor mount,

i like the idea repairing the factory mount by removing all of the stock rubber and replacing with the flexane 80

is the 1lb kit enough to complete the job?

thanks, ked

F1 web Services

[insite]

getting ready to redo my motor mount,

i like the idea repairing the factory mount by removing all of the stock rubber and replacing with the flexane 80

is the 1lb kit enough to complete the job?

thanks, ked

the 1lb kit was enough for me to do my motor mount, all four control arms and two strut top mounts. also, you don't remove the factory rubber. you clean it with alcohol and cast the flexane around it.

[John V]

getting ready to redo my motor mount,

i like the idea repairing the factory mount by removing all of the stock rubber and replacing with the flexane 80

is the 1lb kit enough to complete the job?

thanks, ked

the 1lb kit was enough for me to do my motor mount, all four control arms and two strut top mounts. also, you don't remove the factory rubber. you clean it with alcohol and cast the flexane around it.

I removed all the rubber. The downside to that approach is that you have to find a way to align the center portion of the mount relative to the housing. I built a simple jig to do this.

Waste of time since I ended up using another factory mount, but now I have a nice pretty spare.