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04/03/2010

Porsche 944 Engine Mounts

If your steering wheel or bodywork noticeably vibrates when your 944 is idling (sometimes the rev counter will see-saw at idle too) then it is more than likely that your engine mounts need replacing. There are two mounts and the mount on the drivers side is particularly vulnerable and is usually the first to go.

When I first had both my engine mounts replaced I'd not had the car long (2-3 months) and being the middle of winter I didn't fancy doing it myself, so I had the local general motor mechanic do it. Not being a Porsche specialist and because of the age of the car he wasn't sure how much the mounts would cost, so I said I'd source them from somewhere on the internet.

Not having had any quality problems with third party parts before I sourced some brand new mounts from a place in the states through Ebay. They were cheaper than the OEM (Original Equipment Manufacturer) equivalent so I ordered them and they arrived in a few days. I gave them to the mechanic who then fitted them. He showed me the old mounts and especially the drivers side one was noticeably crushed down more than the other and the rubber had split.

So, nearly a year and a half on I'm writing this post to clear up some things I've found out since.

HERE'S WHAT I KNOW NOW

1. Symptoms of worn engine mounts (Click images for larger versions)



2. Engine mount modifications (OLD Version on Left, NEW Version on Right)



3. How to remove and install engine mounts (Click image for larger version)


As further reference you can use these guides to remove the engine mounts



4. The Engine Mount Heat Protection Plate

If you refer to point 5 in the removal instructions above you will notice it mentions removing the shield for the right engine mount. This is in fact known at the 'heat protection plate' (See part No.19 in the diagram below)

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I would recommend that every 944 owner checks that they have one as upon checking my own car after the 2nd set of engine mounts were recently installed I found that mine was missing. This may explain why the previous 3rd Party engine mount on this side deteriorated (about 15 months) so quickly due to it being cooked by the heat from the engine manifold.

Here's what to look for on the right side of the engine by the exhaust manifold. The orange arrow points to upper one of two mounting posts for the heat protection plate.


Here's the same shot but a wider view showing a missing heat protection plate


And now here's the same shot again but showing the heat protection plate correctly attached


Her are a couple of photos of the heat protection plate itself



The heat protection plate costs about £23 direct from Porsche and has the following part numbers depending on your version of the 944 (right/left hand drive).


944-341-107-01 LL
951-341-108-02 LL
945-341-107-01 RL > My right hand drive 1984 944 (In the photos above)
952-341-108-02 RL


5. Even though OEM Porsche engine mounts and some third party mounts look the same they are NOT.

Third party mount (solid rubber)


OEM Porsche mount (hydraulic)


6. Genuine OEM Porsche engine mounts for a 944 or 944 Turbo WILL ALWAYS BE 'hydraulic'. This means that the black rubber middle is filled with fluid. When these mounts wear out the rubber will often split and the fluid escapes. When you buy 944 mounts from Porsche they will be the uprated 944 Turbo ones (Product code 951 375 042 04) and are roughly £130 each.

7. Solid rubber mounts I have been informed by Porsche are actually only meant for the 924 even though they have exactly the same fitting as the 944. I did not know this when I purchased mine from Ebay and having looked on various Porsche parts sites since and inquired about the hydraulic version it seems that actually a lot of people are only selling the solid rubber ones. My 1st pair of Third Party solid rubber mounts from Ebay cost about £55 each, my 2nd pair of Genuine Porsche Hydraulic mounts cost £127 each.

I initially replaced the engine mounts in December 2008 with the Third Party Solid Rubber variant and then when I noticed engine vibration 18 months later I had them replaced with Genuine Porsche Hydraulic mounts.

Below are the Third Party solid rubber mounts once they were removed from the car.


Notice the mount on the right (UK Drivers Side) is considerably crushed down more than the one on the left. I measured the heights of the detensioned mounts and found that the one on the right was at 63mm which is 2mm below the recommended level. The one on the left measured at 68mm which is OK and is between the 65-70mm tolerance recommended by Porche (See point 1 at the beginning of the post)


(63mm mount)

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(68mm mount)



Here's a couple of photos of one of the brand new Genuine Porsche engine mounts (Left) alongside one of the Third Party ones (Right)





8. Third party mounts DON'T always look the same, here's some others.





CONCLUSION

In my opinion and based on my experiences I would only consider using the 3rd Party solid rubber mounts in two instances. In the first instance I would use them if you intend selling the car within 6-12 months as a means of solving engine vibration that could affect the sale price of the vehicle. And in the second instance I think you could probably use the solid rubber variety on the left side only (as this takes less weight and heat from the engine) if you are trying to save a few quid, but would always use the more expensive hydraulic ones on the right. Therefore if you intend keeping the car for the long term ie. 2 years+ then it would be wiser to go for the more durable genuine Hydraulic mounts from Porsche because the awkwardness and cost of doing the job is something you would want to avoid repeating too often.

25 comments:

  1. Very comprehensive and accurate review of this 944 weak point. Genuine Porsche mounts are definitely the answer. Bert Gear at Berlyn Services has genuine ones for GBP75 each which is the cheapest I've found.

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  2. Thanks for info Founf it very helpful

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  3. Very helpful and the reply with price at Berlyn services as I could only find low price in the us so about same with interntional postage [and susequent delay and poss import duty]

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  4. Probably one of the best plain English assessments of engine mounts I have seen and the images make it an even more enjoyable read. On behalf of most I would think, thanks for going to so much effort. Greatly appreciated.
    Cheers.

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  5. WT* I'm going to check on my '87 heat shield right now - so can the heat shield be installed without steps 1-4?

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  6. Yep, heat shield can be added or removed whenever you like, it's the first thing to be removed and the last go on when you're putting it all back together. Very easy job.

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    1. Would you say you've noticed a difference in the level of vibration or how smooth the engine is at idle with the OEM hydraulic mounts vs. the third party rubber mounts? When I picked up my '87 944 last year, I installed some new third party mounts due to a rough idle and did not see an appreciable level of improvement. The job is a PITA, and the only way I'd want to do that again is if I'm going to get significant improvement. Thanks for a great writeup!

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  7. At first I wouldn't say there is much of a difference, however the OEM mounts that are on my car now have been on there for pretty much twice the length of time that the 3rd party ones were and they are still as good as the day I got them. The 3rd party ones (especially the drivers side one) only lasted about a year from new.

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  8. My 944 turbo 1986 revs @ 800 rpm when idle, it does vibrate the whole car...

    Should I see a mechanic?

    Johnny

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  9. Probably best, if you take it to someone that works on Porsches they'll be able to tell you straight out if your engine mounts need changing

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  10. Thanks for posting this. Real engineering logic...much appreciated

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  11. it sounds like you can do either mount independently of the other - or do you think it is worth it to do both since I suppose the engine is hoisted already.

    i.e. how much work is repeated if you replace a single mount?

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  12. did you raise/secure the engine with the tool described in the manual, the floor-jack+wooden plank method, or something else?

    can you comment on the method?

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  13. Most people use the wooden plank and floor jack method. I had a mechanic do both mine both times as it was the wrong time of year to be getting under the car, too cold in the UK. The mount on the exhaust manifold side is the harder of the two to do, but the basic procedure is the same for both.

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  14. a wooden plank between a floor jack sounds tipsy - did you just go for it, or are there little things that help - e.g. hockey pucks?

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  15. It should be okay. Just to be sure we are not getting our lines crossed the plank and jack are only used to take the weight off the mounts just enough so you can wiggle them out. A second jack and axle stands should be supporting the weight of the front of the car separately. Just wanted to make it clear that you are not jacking the car up on a single jack and plank. Sounds daft but better to be safe.

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  16. [ not sure how to quote]
    > A second jack and axle stands should be supporting the weight of the front >of the car separately. Just wanted to make it clear

    yes, I follow.

    but are you saying you can do either mount with one jack stand under the same side as the mount, or is it better to have two stands on both sides for either one or two mounts?

    hope THAT is clear.

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  17. Hi, ideally you need two stands supporting the car on the front jacking points. You cannot use the cross member as a jacking point for this particular piece of maintenance as you have to loosen the crossmember mounting bolts to aid the removal of the engine mounts. The jack and wooden plank should be used to support the weight of the engine by positioning it to jack up under the oil pan. I've added a link to the bottom of the post that reference Clark's garage tutorial. Hope that helps.

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  18. thanks a lot - hopefully just one last question : how far is too far to jack up the engine?

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  19. As little as you can get away with, just enough so you can edge out the old mounts and slot the new ones in. It's a fiddly job. Remember you are only using the jack and plank to support the weight of the engine and take the mass off the mounts so they can be released. Cheers

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  20. Well done, For my 1986 Lux this info is perfect especially with the pictures, cheers Neil

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  21. This was a really great post. Very useful information supplied. I have 2 944's a 1984 and a 1985 both of which vibrate terribly at idle. New engine mounts it is. Cheers

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  22. Did you find you had to unscrew the universal joint from the steering gear? It seems like this step was not included in the Clark's write up, and I'd like to avoid it if I didn't have to risk it being misaligned when I reassemble it. Thanks!

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    Replies
    1. Yes you do, it's not a problem if the alignment is off as you can always correct it by removing and adjusting the alignment at the steering wheel.

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