W124 spring installation ... "paste"?
 

Getting ready to reinstall the springs on my newly welded-in perches (yikes) and reading over the FSM procedure it says to "use installation paste when installing rubber mount" (ie the mount at the top) ... what is that? Is it OK to install without that assuming I don't have trouble getting the rubber into the perch. I don't recall seeing any use of a paste when reading DIYs so I wasn't sure what the purpose and how necessary it is, and if it is, what kind of paste I can use.

A lanolin based grease like LanoCote (available at marine supply stores) would be ideal.

My guess is the lubricant is recommended to weatherproof the rubber and prevent corrosion of the spring and perch.

Uses for Liquid Lanolin | eHow

I used tire mounting paste. I got a small quantity from a tire shop that looks and feels very similar to the MB paste (that I also have but could not find when I did my springs).

Is it similar to the MB brake paste? Also, it doesn't specify where to use it ... Between the spring and mount, or mount and perch, or both? I know this isn't rocket science but I'm very determined to get this right as I put so much work in repairing the perches.

I would think that brake paste would be petroleum based (but I don't know) which you would not want on the rubber.
The installation paste would go between the rubber and perch.

i'll usually brush a bit of silicone paste on the spring pad where the edge of the springs sits in and smear a bit where the pad is in contact with the perch. when you put them in dry, occasionally (not always) you'll get the spring making a groaning noise as it's trying to shift the pad.

for what it's worth, pelican sells a cheap little tub of suspension grease that's heavy and perfect for the application. less is more. dab a couple spots on the parts and spread thinly with finger. should do the trick .

the paste replacement can be either silglyde or regular silicon di-electric grease.

silicone grease is better as it literally sheds off water. The paste is to prevent the pad squeaking and groaning and also to prevent water trapment and eventual rust.

for low cost of it - go to home depot or lowes and buy the little 2 dollar tube from the faucet repair rack. (it should say silicone grease - dont use the other plumber type).. NAPA/AGS silglyde is good too but is not a silicone grease, it works great on rubber though.

real homebrew style would be castor oil to lube rubber parts.. :D

Thanks for all the advice guys. I got some sil-glyde and put a thin film all around the outside of the mount and between the spring and mount. Here's hoping I have no issues with rust there again.

That rubber mount naturally moves when the coils move. I've seen several spring perches have their paint worn off from the rubber mount. Before installing the springs, I would consider adding a coat of por15 in that area for added wear protection. And then install a coat of MB paste or similar.

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