gasket sealant confusion
 

i have searched and researched:book: for the last 4 or so hours and am really confused. I am installing a thermostat on a 1994 c280. i want to make sure to have everything i need before i start. I see many posts that call for loctite 5900 sealand or even 5970. i have also seen something called permatek "right stuff." I called the dealer and they brushed me away from the purchase of the mb brand sealand because it is $39 for a small tube and was referred to pep boys to find a permatek brand (nice, what an awesome salesperson... if i were his boss :grim: i would have fired him:behead:... there goes his comission..hehe) what should i use for the sealant:confused:?

thanks

I don't think you need to use sealant when replacing a thermostat. I never have, and I've never seen evidence of old sealant on the water pump, and nothing is mentioned in the repair sheet (20-1100).

There's a black rubber o-ring seal that needs to be replaced, but one should come with the thermostat you shouldn't need to purchase anything extra.

Torque on the thermostat housing cover bolts is 9 Nm. Don't overtorque and snap the bolts, replacing that water pump is not trivial (did it this past weekend though, yay me).

Using any sealant on gaskets is a waste of money.

MOST MB applications that require sealant are metal to metal surfaces.

Yep...and doing so will likely cause a leak as the gasket is all that was intended to be there to begin with. Make sure surface is clean, smooth and not gouged from using gasket removal tool.