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Replacing Motor Mounts, Solid, Hyd??

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Old 10-30-2008, 02:19 PM
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wag
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Default Replacing Motor Mounts, Solid, Hyd??

This winter, I will tackle the MM project on my 85s, 5 speed. There has been a lot of discussions on the hyd vrs. solid mounts on these cars. Porsche has the hyd of course and they do not do anything with multiple reasons, yet it seems that a lot of you have put in solid mounts with great success and praise of them. This appears to be one of those jobs, that I do not want to do a year down the road.

Which are better in the long run? I was looking at the Anchor mounts #2698 or the solid mounts offered by 928 Motor Sports? Has anyone had the Anchor's in there cars for a long period of time to evual them?? Does the solid mounts sag after a while??
Old 10-30-2008, 02:39 PM
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Mrmerlin
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Call Roger he has the solid mounts with fitment hardware,and they are reasonably priced also consider taking 2 flat washers(about 1 1/2 in in diameter) to put on the lower mount ( tween the crossmember and the mount) This will add just a bit more to the lift of the motor.
Be very careful when reinstalling the rack as the left side mounting stud can sometimes contact one of the hoses that run along the top of the rack, it seems as every fitment is different. The other option along with fitting the washers is to premeasure the lower stud with nut on it then cut the rest of it off prior to fitting in the crossmember it would be best to check both sides
Old 10-30-2008, 03:47 PM
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JHowell37
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While it's apart, consider replacing your steering rack bushings at the same time and the oil pan gasket. If you really want to improve the car in one shot, change the transmission mounts as well. It's much easier then the motor mounts and the difference is almost as profound.
Old 10-30-2008, 04:01 PM
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mj1pate
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ditto on solids. The solids purchased from Roger provide completely adequate vibration isolation.
Old 10-30-2008, 05:43 PM
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UKKid35
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Originally Posted by mj1pate
ditto on solids. The solids purchased from Roger provide completely adequate vibration isolation.
Do you think they're only supposed to insulate the chassis from vibration? I think you've missed the point.

Solid mounts might be just barely adequate for a slush box, but if you have a manual car then I would suggest that having the shock insulation that the hydraulics provide is important to protect your drive train effectively.

Who cares if they fail after 10 or 15 years? They are consumables - like brake discs, shock absorbers and tyres. They are a little more awkward to replace, but so is a cam belt, and you only get 5 years out of a cam belt.
Old 10-30-2008, 06:04 PM
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VehiGAZ
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Originally Posted by UKKid35
Solid mounts might be just barely adequate for a slush box, but if you have a manual car then I would suggest that having the shock insulation that the hydraulics provide is important to protect your drive train effectively.
Is this true?


I am considering replacing the engine mounts on my '89 GT next week - there is waaaaay more vibration coming through the shifter, wheel, pedals, etc than I would expect of a $75k car. It's all-the-time vibration, not just at certain rpms.

Should I replace both the engine & tranny mounts? Should I really use the OEM hydraulic mounts with a manual tranny? (please say no that second part...)
Old 10-30-2008, 06:23 PM
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UKKid35
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I'm not rich enough to use OEM Hydraulics, I used the Anchors at $20 each.
Old 10-30-2008, 06:37 PM
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Gaz it sounds like your mounts have collapsed to the point of having the internal metal housing pressing on the lower housing of the mount this transfers all the vibes to the chassis. The oil pan could also be hitting the crossmember.
As far as hydro mounts or solids your not going to notice much of a difference but the hydro mounts do seem to fail sooner than the solids,(The liquid leaks out)
Really what your looking for here is smoothness and that the mounts maintain their height, it keeps the driveline in its correct postion, once the mounts collapse then the foam heat sheild is letting in more hot air from under the TT area and the engine oil pan will be siiting close if not touching the crossmember.
Old 10-30-2008, 07:05 PM
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Landseer
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I've put three pairs on this year (different cars of course).
Excellent. Go solid.
Old 10-30-2008, 07:06 PM
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Shark Attack
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I put in the solids. Why? I dunno.... they work and made a big improvment.
Old 10-30-2008, 07:26 PM
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UKKid35
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I'm guessing that the solid rubber mounts are perfectly capable of damping high-frequency, low-amplitude vibrations, but low-frequency, high-amplitude engine vibrations (or acceleration/deceleration shocks) are dealt with much more effectively by the hydraulics. The only evidence I can offer for the theory that solid mounts are inadequate is that Porsche went to the expense of developing and fitting hydralics after originally fitting solid mounts. You have to ask yourself why.
Old 10-30-2008, 07:52 PM
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wildwestsydney
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Originally Posted by Mrmerlin
Call Roger he has the solid mounts with fitment hardware,and they are reasonably priced also consider taking 2 flat washers(about 1 1/2 in in diameter) to put on the lower mount ( tween the crossmember and the mount) This will add just a bit more to the lift of the motor.
Be very careful when reinstalling the rack as the left side mounting stud can sometimes contact one of the hoses that run along the top of the rack, it seems as every fitment is different. The other option along with fitting the washers is to premeasure the lower stud with nut on it then cut the rest of it off prior to fitting in the crossmember it would be best to check both sides
I used Rogers mounts, very good price and a good product. Very good tip on the tip on the power steering line contacting the mount stud. I have to let the rack down and grind down the length of the stud coming through the crossmember due to slight interference.

On a side note I noticed my steering wheel not being centered after the job. The steering shaft never came out of the splined universal. I did take the bolt out and move the shaft back in the universal. Any thoughts on this from people that have done a motor mount replace.
Old 10-30-2008, 08:37 PM
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OBehave
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I have an 84 5spd S and I used the Anchor solids purchased locally for $35 each and a self made 6mm spacer for the bottom of the mount and the difference was unbelieveable!!!!All of the vibrations and such was gone and the oil pan was above the crossmember so the was no clearence issues.
General opinions on Rennlist is go anchor and I would agree!Besides if they only last 50,000 miles you still come out ahead if you do the job 3 times in the life of your ownership.
Old 10-30-2008, 09:20 PM
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wag
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To Everyone: Thank you for all of your input. This is why I wanted to get a good reading on this issue. There is a lot of speculation out there on these parts, which is better or worse. With the new parts that are coming out and updating of the old style parts and all, some of these replacement parts may not have been available back when the cars were in production. Hope to get more input from you guys on this issue !!!
Old 10-30-2008, 10:03 PM
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VehiGAZ
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Originally Posted by UKKid35
Porsche went to the expense of developing and fitting hydralics after originally fitting solid mounts. You have to ask yourself why.
I keep asking myself why... did Porsche put two windshield washer systems?!? Why do I have a 3-mode rear defrost?!?


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