Rear diff cover sealant. Is there a paper gasket fot this? - PeachParts Mercedes-Benz Forum

turbobenz · #1 05-12-2010, 04:43 PM

I'm going to be working on a car that needs the CV axles replaced but I'm wondering if there is any way around the 24hour cure time of RTV sealant. Can you buy a paper gasket for the cover? Basically I need to put the car back together so she can drive it home that day however it looks like I may be giving her a ride. what if I took a spare diff cover and coated it in a thin layer of RTV the day before? Id imagine compressing the rtv like that would stress it and break the seal. Any ideas? I dont see a paper gasket in AllPartsExpress or any other sites. It really seems like there should be a paper gasket for this

Shawn T. W. · #2 05-12-2010, 04:55 PM

When I did mine I just used a thin layer of RTV, and once the bolts were tightened I added oil . . . no problems, and that was 10k mi ago!

They do not have paper type gaskets for them . . .

andrewjtx · #3 05-12-2010, 05:37 PM

Quote:

Originally Posted by turbobenz

I'm going to be working on a car that needs the CV axles replaced but I'm wondering if there is any way around the 24hour cure time of RTV sealant.

This is not something you want to rush. If you don't have a weekend to do this job, I wouldn't.

pawoSD · #4 05-12-2010, 05:52 PM

We used the proper $23 a tube MB sealant. That stuff is insane! There's enough in one tube to do maybe 3 diffs....

SirNik84 · #5 05-12-2010, 07:02 PM

This is the stuff I used on my dads transfer case. no leaks.
http://www.permatex.com/products/Automotive/automotive_gasketing/gasket_sealants/auto_Permatex_Form-A-Gasket_No_1_Sealant.htm
Come to think if it, I used this stuff on Sharons diff on her 300d.

looking around the permatex site, this may be better, but it says it needs 24hrs to cure.

http://www.permatex.com/products/Automotive/automotive_gasketing/gasket_makers/permatex_gear_oil_rtv_sealant.htm

Maybe this stuff.
http://www.permatex.com/products/Automotive/automotive_gasketing/specialty_gasket_maker/MotoSeal_1_Ultimate_Gasket_Maker_Grey.htm

Check out the TDS PDFs

charmalu · #6 05-12-2010, 07:28 PM

I used the permatex Ultra-Grey for the cover.

Charlie

Diesel911 · #7 05-12-2010, 07:46 PM

Remember the often stated advice of making sure you can remove the Oil Filler Plug before your take the back Plate of the Differential off; or you will have no way to refill it later.

Any of the above stuff mentioned by the other members will work as will the non-hardening #2 Permatex.
While old school the brown #1 and #2 Permatex does not need any cure time. They are more of a mess to clean off the next time you do the job.

The is not enought pressure in a differential to force out the already very tick Oil. Also most differentials have a Breather so pressure does not build up inside.

turbobenz · #8 05-14-2010, 04:31 AM

im just worried about the weight of the oil pushing on the uncured seal. Im considering using grey RTV and just filling it but Ill have to read sirnik's links before I come to a conclusion.

ImBroke · #9 05-14-2010, 06:02 AM

I used the Ultra Black. I apply a thin layer to both surfaces, let it cure 5 minutes before assembly, and then after assembly wait an hour and filled. I've done water pumps this way too, and never had a leak.

vstech · #10 05-14-2010, 08:53 AM

I always let the THIN layer of rtv "SKIN" for 15 minutes, then assemble loosely. wait 1/2 hour. (there's always plenty to do cleanup etc...) then tighten up the bolts and fill with fluid.
hundreds or differentials. no leaks yet.

winmutt · #11 05-14-2010, 09:10 AM

Axles in and out in under a day no problem. Pretty easy job. Just make sure you have the special tool for the C-clip. I use a coat hanger with just the tinniest turn at the end, you will want to fish them from the inside going out. I am using synthetic however my next time in there I may switch to conventional. I get humming above 70 on both mobil1 and whatever I put in there last time, had the same problem with mobil1 on the last diff too.

JHZR2 · #12 05-14-2010, 10:15 AM

Id use the new permatex stuff designed specifically for differential fluid chemistry, and follow directions to whatever extent possible.

A little bit of warming from a hairdryer or heat gun (dont go overboard) will speed up the cure.

69shovlhed · #13 05-14-2010, 11:47 PM

the MB sealant is the best sealant i've ever seen, w/ the possible exception of hylomar. i use it for all my vehicles-- it even sealed the rocker boxes on my harley, and i've seen alot of leaking rocker boxes even on the bikes of good mechanics. it is worth every penny. use it sparingly, and don't spread it out before putting the parts together. 1/8" bead is all it takes most times. seals diff covers, and at the dealer we don't take time to let it cure, other than the time it takes to put it back in the car. fill it up and go. no leaks.

teezer · #14 05-15-2010, 08:09 AM

i use HondaBond, available through Honda motorcycle shops

HondaBond (3.5 oz)

HT Formula that is an adhesive sealer for metal-to-metal, metal-to-plastic, or plastic-to-plastic bonding. Good for high temperature applications.

69shovlhed · #15 05-15-2010, 08:40 AM

Quote:

Originally Posted by teezer

i use HondaBond, available through Honda motorcycle shops

HondaBond (3.5 oz)

HT Formula that is an adhesive sealer for metal-to-metal, metal-to-plastic, or plastic-to-plastic bonding. Good for high temperature applications.

wonder if thats the same as yamabond? pretty good stuff, but the MB sealer is better still.