Is this factory o ring

[kavadarci]

Hi,
I finally addressed the triangle of death that had oil leaks and probably all was coming from the thermostat.

When I removed the thermostat the o ring was black and hard plastic broke in half when I tried to remove it.

The new one I bought is red and was wondering if the black is factory o ring?

[KTL]

Black is likely not a factory o-ring. Original o-rings are usually brown/orange. But I haven't seen every type of regular production 911 to be certain of that color claim.

Did you also check the condition of the end of the breather hose? I would cut off a segment of that hose if the end is at all hard. Cutting off the end gives you a "fresh" piece of softer hose to better seal onto the engine case vent neck.

Did you change that oil pressure warning light switch? That sucker is notorious for leaking at the crimp joint between the plastic and metal. Not a bad idea to coat a new one with epoxy around the crimp joint.

What's that white paste all over the new o-ring area?

[proporsche]

actually ,the original o ring were black..so yours was there for a long time.Then they come up with orange and brown and finally green Viton o-rigs
The only time you can see this o ring brittle is the black , it became very hard, like a plastic.So the change was made to orange and brown later..

Ivan

[john walker's workshop]

Green Viton will outlast the red ones.

[kavadarci]

Originally Posted by KTL

Black is likely not a factory o-ring. Original o-rings are usually brown/orange. But I haven't seen every type of regular production 911 to be certain of that color claim.

Did you also check the condition of the end of the breather hose? I would cut off a segment of that hose if the end is at all hard. Cutting off the end gives you a "fresh" piece of softer hose to better seal onto the engine case vent neck.

Did you change that oil pressure warning light switch? That sucker is notorious for leaking at the crimp joint between the plastic and metal. Not a bad idea to coat a new one with epoxy around the crimp joint.

What's that white paste all over the new o-ring area?

To answer your questions:
Yes, I have checked the breather hose and it is SOLID, feels like it's metal with rubber on the outside. I will not be using it as i have new high quality hose.
I did remove the oil pressure warning light switch and looked great, new washer and epoxy around was applied. Maybe i should change the whole thing.. Not a bad idea.
Do you know what is the part number? i can't find same with the red top.

the white paste is molykote 55 for o rings which was highly recommended by forum members for any o ring applications. it should keep the o ring rubbery and flexible for a good amount of time (or so they say).

[proporsche]

as JW. said ...i only use Viton green o rings on the 911..they last for ever
Ivan