Oil Leak tracing

Technical Guidance for doing those Tricky Jobs

Moderators: timk, Stu, zombie, Andrew, -alex, miata, PUR157

Snowmotion
Racing Driver
Posts: 750
Joined: Mon Jul 29, 2013 8:47 pm
Vehicle: NC
Location: Sydney

Oil Leak tracing

Postby Snowmotion » Tue Sep 10, 2013 2:34 pm

Hi

I am new MX5 owner and purchase my NB8a with some oil leaks.

I hoped a timing belt change, crank seal, cam seals, water pump and valve cover seals would solve these problems. I did this on Friday and have been for a few short drives since.
Whilst getting a wheel alignment this morning I heard one of the Aux belts squealing and thought that odd as I had carefully adjusted them.
When I opened the bonnet I noticed a couple of drops of oil on the plastic cover and then looked up the motor and noticed a fresh oil leak.
There was a small dribble of oil coming down the lower timing belt cover on the drivers side (where it joins the other half of the lower cover) and oil sitting on the top of the oil pan.

I was very careful with the orientation of the cam seal and tapped it in carefully with a pvc pipe of the same size.

As the oil is on top of the oil pan i am thinking it is leaking some where higher on the motor.
Can any one offer any suggestions of the likely source?
I can post some pictures tonight if that will help.

Cheers
Andy
NB8A| WP 1:15.6 | SMP-S 1:08.56 | SMP-N 1:21.35
NC1| WP 1:09.42 | SMP-S 1:03.191 | SMP-N 1:16.1856 | SMP-GP 1:48.288

User avatar
NitroDann
Forum sponsor
Posts: 10280
Joined: Thu Nov 05, 2009 12:10 pm
Vehicle: NA6
Location: Newcastle NSW
Contact:

Re: Oil Leak tracing

Postby NitroDann » Tue Sep 10, 2013 3:41 pm

Cam seals, front main or cam cover.

Just pull it apart and look :)

Dann
http://www.NitroDann.com

speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

Snowmotion
Racing Driver
Posts: 750
Joined: Mon Jul 29, 2013 8:47 pm
Vehicle: NC
Location: Sydney

Re: Oil Leak tracing

Postby Snowmotion » Tue Sep 10, 2013 3:47 pm

Thanks Dan

I will pull the covers off and check but I did replace the Cam seals x 2 and Crank seal.
I have checked the Valve cover and no oil coming from there.

Cheers
Andy
NB8A| WP 1:15.6 | SMP-S 1:08.56 | SMP-N 1:21.35
NC1| WP 1:09.42 | SMP-S 1:03.191 | SMP-N 1:16.1856 | SMP-GP 1:48.288

Snowmotion
Racing Driver
Posts: 750
Joined: Mon Jul 29, 2013 8:47 pm
Vehicle: NC
Location: Sydney

Re: Oil Leak tracing

Postby Snowmotion » Tue Sep 10, 2013 9:18 pm

so pulled the timing belt covers off tonight and looks like it is the inlet cam seal that is leaking.

Now why?
How to solve?
NB8A| WP 1:15.6 | SMP-S 1:08.56 | SMP-N 1:21.35
NC1| WP 1:09.42 | SMP-S 1:03.191 | SMP-N 1:16.1856 | SMP-GP 1:48.288

User avatar
NitroDann
Forum sponsor
Posts: 10280
Joined: Thu Nov 05, 2009 12:10 pm
Vehicle: NA6
Location: Newcastle NSW
Contact:

Re: Oil Leak tracing

Postby NitroDann » Tue Sep 10, 2013 9:19 pm

Did you put it in properly?

From its inside or outside?

Is the cam worn on the sealing surface?

Dann
http://www.NitroDann.com

speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

Snowmotion
Racing Driver
Posts: 750
Joined: Mon Jul 29, 2013 8:47 pm
Vehicle: NC
Location: Sydney

Re: Oil Leak tracing

Postby Snowmotion » Tue Sep 10, 2013 9:35 pm

I will pull the cam cover off tomorrow night (it is no fun working in the open st night) and see if I can see where.
At the moment I am seeing this looking through the cam sproket.
Image

This car had been leaking oil when purchased so suspect this may be an old problem with the Cam surface.
NB8A| WP 1:15.6 | SMP-S 1:08.56 | SMP-N 1:21.35
NC1| WP 1:09.42 | SMP-S 1:03.191 | SMP-N 1:16.1856 | SMP-GP 1:48.288

User avatar
NitroDann
Forum sponsor
Posts: 10280
Joined: Thu Nov 05, 2009 12:10 pm
Vehicle: NA6
Location: Newcastle NSW
Contact:

Re: Oil Leak tracing

Postby NitroDann » Tue Sep 10, 2013 9:49 pm

The seal inner lip can be fitted so that it is folded.

Are you sure you didnt do this? is the leak coming from between the seal and the surrounds or the seal and the cam?

Dann
http://www.NitroDann.com

speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

Snowmotion
Racing Driver
Posts: 750
Joined: Mon Jul 29, 2013 8:47 pm
Vehicle: NC
Location: Sydney

Re: Oil Leak tracing

Postby Snowmotion » Tue Sep 10, 2013 9:54 pm

I will get up early in the morning and pull off the valve cover to check.
NB8A| WP 1:15.6 | SMP-S 1:08.56 | SMP-N 1:21.35
NC1| WP 1:09.42 | SMP-S 1:03.191 | SMP-N 1:16.1856 | SMP-GP 1:48.288

Snowmotion
Racing Driver
Posts: 750
Joined: Mon Jul 29, 2013 8:47 pm
Vehicle: NC
Location: Sydney

Re: Oil Leak tracing

Postby Snowmotion » Wed Sep 11, 2013 8:35 am

Dan, you know too much.. thank you.

Cam seal with folded lip... :?

Image

Will get a new one today and refit .... with more care this time.
NB8A| WP 1:15.6 | SMP-S 1:08.56 | SMP-N 1:21.35
NC1| WP 1:09.42 | SMP-S 1:03.191 | SMP-N 1:16.1856 | SMP-GP 1:48.288

User avatar
NitroDann
Forum sponsor
Posts: 10280
Joined: Thu Nov 05, 2009 12:10 pm
Vehicle: NA6
Location: Newcastle NSW
Contact:

Re: Oil Leak tracing

Postby NitroDann » Wed Sep 11, 2013 8:49 am

Wicked, easy fix :)

Dann
http://www.NitroDann.com

speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

Snowmotion
Racing Driver
Posts: 750
Joined: Mon Jul 29, 2013 8:47 pm
Vehicle: NC
Location: Sydney

Re: Oil Leak tracing

Postby Snowmotion » Thu Sep 12, 2013 2:13 pm

Seal changed and back together.. :D

See how she goes on the weekend.
NB8A| WP 1:15.6 | SMP-S 1:08.56 | SMP-N 1:21.35
NC1| WP 1:09.42 | SMP-S 1:03.191 | SMP-N 1:16.1856 | SMP-GP 1:48.288


Return to “MX5 Technical Guides”

Who is online

Users browsing this forum: No registered users and 35 guests