NA8 Leaks

Engines, Transmissions & Final Drive questions and answers

Moderators: timk, Stu, zombie, Andrew, The American, Lokiel, -alex, miata, StanTheMan, greenMachine, ManiacLachy, Daffy

User avatar
dmad_dood
Fast Driver
Posts: 275
Joined: Wed Dec 19, 2012 8:16 pm
Vehicle: NA8

NA8 Leaks

Postby dmad_dood » Thu Jun 20, 2013 10:22 pm

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.
Red NA8..

User avatar
Steampunk
Speed Racer
Posts: 4670
Joined: Wed Oct 10, 2007 9:16 am
Vehicle: NA6
Location: Southside of Breeze-bane

Re: NA8 Leaks

Postby Steampunk » Thu Jun 20, 2013 11:26 pm

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.
Image

koop21
Fast Driver
Posts: 296
Joined: Tue Aug 23, 2011 12:31 am
Vehicle: NA6
Location: Sydney

Re: NA8 Leaks

Postby koop21 » Thu Jun 20, 2013 11:49 pm

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.

manga_blue
Forum Guru
Posts: 4897
Joined: Mon Apr 24, 2006 7:27 pm
Vehicle: NA8
Location: Moruya, NSW

Re: NA8 Leaks

Postby manga_blue » Fri Jun 21, 2013 12:04 am

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.
’95 NA8

User avatar
dmad_dood
Fast Driver
Posts: 275
Joined: Wed Dec 19, 2012 8:16 pm
Vehicle: NA8

Re: NA8 Leaks

Postby dmad_dood » Fri Jun 21, 2013 7:46 am

All good points. Do i need a torque wrench to put the gasket back on if i take it off?
Red NA8..

User avatar
dmad_dood
Fast Driver
Posts: 275
Joined: Wed Dec 19, 2012 8:16 pm
Vehicle: NA8

Re: NA8 Leaks

Postby dmad_dood » Fri Jun 21, 2013 9:12 pm

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?
Red NA8..

User avatar
KevGoat
Speed Racer
Posts: 3940
Joined: Sun Jun 17, 2012 8:48 pm
Vehicle: NB SE
Location: Down South, Adelaide, SA

Re: NA8 Leaks

Postby KevGoat » Fri Jun 21, 2013 10:18 pm

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...

User avatar
dmad_dood
Fast Driver
Posts: 275
Joined: Wed Dec 19, 2012 8:16 pm
Vehicle: NA8

Re: NA8 Leaks

Postby dmad_dood » Mon Jun 24, 2013 6:30 pm

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.
Red NA8..

User avatar
CQYD
Fast Driver
Posts: 125
Joined: Tue Feb 03, 2009 6:02 pm
Vehicle: NA8

Re: NA8 Leaks

Postby CQYD » Wed Jun 26, 2013 1:16 pm

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.

User avatar
aka_juffa
Racing Driver
Posts: 1005
Joined: Wed Dec 14, 2011 2:40 pm
Vehicle: NA8
Location: SE Melbourne.

Re: NA8 Leaks

Postby aka_juffa » Wed Jun 26, 2013 2:22 pm

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.
Motor Neurone Disease chose me, I choose Voluntary Assisted Dying.


Return to “MX5 Engines, Transmission & Final Drive”

Who is online

Users browsing this forum: No registered users and 131 guests