Ok guys, So I have been battling this silly valve cover leak for quiet some time now. I am not sure why, but my VC/gasket jsut can't stop leaking. I replaced the gasket about 4k-5k miles ago because the one that came with the car was leak anyway. I have re-installed it on 5 or 6 seperate occasions in as many ways as possible. I have an in-lb tq. wrench I can use. I use the method in the 99 factory manual (hand highten 11 down, then spiral out from the center in counter-clockwise fashion). I have cleaned both surfaces thoroughly and I move the coil pack out of the way everytime. Is it possible if the coilpack is tightened too much that it would cause the gasket to leak out of the back? (whats where the majority of the leaking is occuring, in the rear and sides). I will post pics. shortly.

 

Did you use RTV?

If not, do that.

 

yes, I actually just redid all of it this weekend. Starting from the beginning:

-Removed VC gasket
-Cleaned the VC notch for the gasket
-install VC gasket into the VC
-Removed old high-temp RTV
-Cleaned off the Head
-put on new RTV
-put the VC on the head again

She seems to have stopped leaking on one side... hard to tell on the intake manifold side, but we will know soon enough. I check my oil daily, but there is still some oil residue left over from before.

Is it an ok solution if its leaking from one side to tighten it down more? (I think tq wise, I am very low right now, that seems to work best its hand tight a bit more).

 

Seems like the correct way from your first post but just to make sure we're on the same page... are you tightening the bolts down in the correct order? Tighten them hand tight in the correct order and then torque them down (43 - 78 INCH-lbs) in the correct order. See this article: http://www.miata.net/garage/valvecover/index.html

 

yes sir, sure do.

 

Yeah the only thing I can think of is the RTV in those corner spots which you mentioned. Have you checked for knicks on the valve cover?

 

yea, thats what I was thinking, but I really don't see anything out of the ordinary on the head or the VC. There seems to be imperfections at the edges (to be expected), but nothing on the seating surface for the gasket.

I did notice that on the intake manifold side, the gasket seems to droop over the seating surface when torqued as its so close to the edge. anyone else experience that? I can push it inwards some, but it makes threading the bolts in pretty difficult.

 

Ok, first thing first, did you buy a flat packed gasket or was it rolled or folded up. If it wasn't flat, bite the bullet and go but another gasket. If it was flat, are you putting any sealant on the sealing surface other than the 6 points already pointed out, if so then the gasket is probably sliding out when you tension down the cover if your using a RTV sealant.
If it was yes to the first and no to the second then all I can suggest is to use Loctite 515 on the head and tighten down as per earlier suggestions, remembering that the tension in the manual are a max not a min.
How do I know all this ? Experience as a master tech and time working as a trainer and warranty adjudicator for a Japanese manufacture.

Terry

 

cool cool, sorry I forgot to post back. I fixed the leak, just took some ***** and a bit more tightening on the intake side. While the gasket is slightly wet on that side, my oil has stabilized. I assume the wetness on the gasket is just left over oil that was seeping.

I don't think I was overtightening it anyway, if anything I was undertightening it.