Replacing Lower Valve Cover Gaskets?

[911TT33]

Hey guys,

I'm planning to replace my lower valve covers shortly (on my 3.2 Carrera), with new billet ones that have been machined for twin plugs.

When I remove my old valve covers, what's the best way to install the new valve cover gaskets?

Do I need to apply anything to both sides of the gaskets for a better seal?

I read somewhere to spray some WD40 on both sides before installing?

I also read to start with the center bolts first, then work my way outwards on both sides in a "star" pattern? What exactly does this mean?

Advice greatly appreciated!

[wazzz]

Seems to be the correct bolting pattern, as you want to press the center first then press each end next. If you press each end first, this might make the cover very slightly convex and more prone to oil leaks.

As for the gaskets, I personally set them dry and never had a leak with stock covers and new nuts and crush washers.

[911TT33]

Originally Posted by wazzz

Seems to be the correct bolting pattern, as you want to press the center first then press each end next. If you press each end first, this might make the cover very slightly convex and more prone to oil leaks.

As for the gaskets, I personally set them dry and never had a leak with stock covers and new nuts and crush washers.

Thanks, Wazzz 👍🏼

[porschedude996]

I personally like the gaskets where the lower ones have a raised bead of green silicone already on the surface. I like p/n 911-105-902-50. I set them dry as Wazzz stated.

If the surface is flat and clean and free of any oil, they should seal leak free.

You can check the surface of the cover on a flat surface like a piece of glass. And the cam housing with a straight edge.Then without gaskets, put the cover on and check to make sure it doesn’t rock around. I noticed that the cover makes a certain sound when it’s flat on both surfaces. It’s kind of a “Clopping” noise, like a horse’s hoof on a hard surface.

With all the that, tighten them down with a 1/4” ratchet until you reach a point where the nut stops. I generally start from the inside out, jumping from top to bottom as I work out. When you are there with all feeling the same with the 1/4” drive, use a torque wrench. I use 20 ft lbs in progression. (10ft lbs, then 20 ft lbs). New nuts will have a higher running torque when first run down.

In the Aerospace world, the running torque is measured and added to the desired final torque. But this is not “Rocket Science “.

[911TT33]

Originally Posted by porschedude996

I personally like the gaskets where the lower ones have a raised bead of green silicone already on the surface. I like p/n 911-105-902-50. I set them dry as Wazzz stated.

If the surface is flat and clean and free of any oil, they should seal leak free.

You can check the surface of the cover on a flat surface like a piece of glass. And the cam housing with a straight edge.Then without gaskets, put the cover on and check to make sure it doesn’t rock around. I noticed that the cover makes a certain sound when it’s flat on both surfaces. It’s kind of a “Clopping” noise, like a horse’s hoof on a hard surface.

With all the that, tighten them down with a 1/4” ratchet until you reach a point where the nut stops. I generally start from the inside out, jumping from top to bottom as I work out. When you are there with all feeling the same with the 1/4” drive, use a torque wrench. I use 20 ft lbs in progression. (10ft lbs, then 20 ft lbs). New nuts will have a higher running torque when first run down.

In the Aerospace world, the running torque is measured and added to the desired final torque. But this is not “Rocket Science “.

Great info, thanks! 🙏🏼

[911obgyn]

I usually do 8-10 then drive for awhile and check for leaks have not had any, i use the green paper gaskets. I will put a bit of grease on the gasket.

[montauk]

I know they're not everyone's favorites but I put on a set of silicon gaskets and no leaks. I only put about 100 miles on them before taking the car off the road a couple of weeks ago to get started on my ITB swap.

[911TT33]

Originally Posted by montauk

I know they're not everyone's favorites but I put on a set of silicon gaskets and no leaks. I only put about 100 miles on them before taking the car off the road a couple of weeks ago to get started on my ITB swap.

How are those silicone gaskets going? Still no leaks?

I ordered them from our host provider too.

What did you torque the nuts down to? 8Nm?

[montauk]

Originally Posted by 911TT33

How are those silicone gaskets going? Still no leaks?

I ordered them from our host provider too.

What did you torque the nuts down to? 8Nm?

My car is still off the road, while I work on my ITB setup, so I haven't done any more miles. I'd say I torqued them to snug. I stopped as soon as I felt a bit of squish and checked all the way around the valve cover to makes sure the cover was sitting evenly.

[bkreigsr]

Why WD-40?

It is a petroleum distillate and will likely corrode any non-metallic surfaces over time.

Do more research - most of the pros don't use any sealer.

(FWIW, 'WD' stands for 'water displacement' formula. (- this was the 40th iteration.)

[911TT33]

Originally Posted by bkreigsr

Why WD-40?

It is a petroleum distillate and will likely corrode any non-metallic surfaces over time.

Do more research - most of the pros don't use any sealer.

(FWIW, 'WD' stands for 'water displacement' formula. (- this was the 40th iteration.)

Yeah thanks. I’ll be installing them dry and torque to 8Nm. See how it goes 👍🏼

[911TT33]

Originally Posted by montauk

My car is still off the road, while I work on my ITB setup, so I haven't done any more miles. I'd say I torqued them to snug. I stopped as soon as I felt a bit of squish and checked all the way around the valve cover to makes sure the cover was sitting evenly.

Will do, thanks. I’ll follow the specs and just torque them to 8Nm.