mx5cartalk.com

Hello all, my na8s got a leak out of the middle of the rocker cover in the middle on the exhaust side. Im confused as its supposedly a brand-new head gasket. I've been told this happens when replaced with aftermarket head gaskets?? Can anyone confirm?

Also i was under my car and noticed quite a lot of fluid of some sort under the gearbox tunnel, couldn't really source the leak with limited access but i've checked oil several times in the interim and its holding steady so maybe its another fluid of sorts.

Do na8s have any common issues downstairs that could cause this, maybe something like a bad/old sump gasket or something like that?

Cheers,

Jono.

Just because it's new doesn't necessarily mean it was fitted properly.
Check the area under the CAS.
Smell the leaking fluid, engine and gearbox lubricant smell different.

dmad_dood wrote:Hello all, my na8s got a leak out of the middle of the rocker cover in the middle on the exhaust side.

Your probably mean the valve cover gasket, if it was your head gasket you will be leaking coolant first... Try tightening down the valve cover bolts a quarter turn more, not too much dont wanna snap those bolts either.

And follow Steampunks suggestions also about the CAS O ring.

If a new cam cover gasket leaks it's usually because it was fitted badly, not because it wasn't OEM. If there's oil above the exhaust then it's probably from that. Take it off, check that it was properly in the slots and re-fit it if it hasn't been damaged.

O-ring around the CAS at the back of the cam cover on the left side is a likely source too. Also when checking what sort of oil is all over the bottom of the gearbox I'd be comparing the feel and smell of it to clutch fluid as well as to engine and gear oil.

All good points. Do i need a torque wrench to put the gasket back on if i take it off?

dmad_dood wrote:All good points. Do i need a torque wrench to put the gasket back on if i take it off?

what should i torque the nuts to?

dmad_dood wrote:All good points. Do i need a torque wrench to put the gasket back on if i take it off?

My NA6 was leaking from the cam cover gasket when I first got it. Just kept tightening the bolts little by little until it stopped. Hasn't leaked for over a year now...

hehehe. cas o ring was the culprit! Reached around the back of the head and when i removed my hand it was very wet with oil indeed.

How big a job is it to fix? Is it something a rookie diy enthusiast could do?

Thanks again for all the help!!

Jono.

I had the CAS o ring replace last year. If you going to DIY make sure you have a timing gun to check your timing afterwards.

Here is a link to the miata.net garage.

http://www.miata.net/garage/garageengine.html

About 1/2 way down the first page there is a couple of handy articles on replacing the CAS seal.

J.