Torque of Plastic Valve Cover Screws

[mdamico]

I was going to change my Valve Cover gasket tonight because I have oil seeping into the 2nd and 3rd Spark Plug holes. The gasket set I got from Mazda is made out of four flat, vertical gaskets. I'm guessing that they fit into slots in the inside the coer. One big one goes around the outside perimeter, two small rectangular ones go around Spark Plugs 1 and 4 (one gsket for for each plug), and then a medium sized one encircles Spark Plugs 2 and 3 (the spark plug holes with oil on them). When I reserarched the torque for the valve cover screws (so I could put it back together right) I got roughly the same torque spec from two different sources: My Mazda dealership let me have a look at the acual Blue Mazda 6 shop manual and it gave a tourqe spec of something like 72 to 92 inch pounds. Then I asked my mechanic at a private garage to look up the torqe spec using his computer resources and they said it was from 70.9 to 101.7 inch pounds. Here is my concern: I checked the torque first off and ALL of my valve cover screws were loose before I started work with the wrench set at 72 inch pounds. When I tightened them up further to around 80 inch pounds, they didn't seem like they were getting tight quickly enough; the screws felt like they were smushing the plastic valve cover too much so I stoped at 80 inchh pounds. I wonder if I didn't get the torque speck correctly for the plastic cover. If anyone knows for sure, please let me know.

BTW, I decided not to change the gasket for the time being because the Valve Cover screws were so loose (compared to the specifications I got). So I will check in a few days to see if any more oil seeped into Spark Plug holes for cylinders 2 & 3. If I see oil, then I guess I'll have to change the gasket after all. So if anyone knows for srure, what the torque is for the Plastic Valve Cover screws, please pass that information back my way.

Thanks!
From Mike D'Amico

[Final Impact]

It shows this:
8.0—10.5 N·m {81.6—107.1 kgf·cm, 70.9—92.9 in·lbf}

I think someone glanced and saw the front cover bolts which list:
8.0—11.5 N·m {81.6—117.2 kgf·cm, 70.9—101.7 in·lbf}

The drawing takes more than glance to see the spec as its foot notes vs proximetry to the item being tightened.

Google:
mazdaserviceinfo 9999–95–LFL3–05

[mdamico]

I didn't write down exactly what the dealership's Mazda 6 Repair maual said because the torque specificaitons were relatively the same as the printed valve cover specifications I received from my other Mechanic's resources: roughly 70 to 92 inch-pounds. One thing that still concerns me though is that the pictures in the manuals still look like a Metal valve cover.
So my question is do the bolts and nuts that hold the cover down loosen over time and you have to re-tighten them to get it to seal properly again? That's the assumption I made for the time being. So now that I've re-tightened the bolts and nuts, in a week's time I'll pull one of the middle plug wires and see if I still have oil seeping into the Spark Plug holes. Does this sound like a good plan?

[Furytom]

Since the rubber gasket will seat a little bit as you torque the screws down I always go around at least a second time in the sequential order to make sure its all torqued down correctly. Dont worry about the plastic cover, it can handle the pressure of the screws even if you over torque it by a bit.

Tomi