mystery oil leak
 

My 96 1.8 natural leaks quite a bit of oil between 5000mile oil changes.

I only notice a few drips in the driveway after being parked there is no smoking only a wiff of hot/burnt oil when I stop after a highway drive.

I can't tell where its coming from. Engine has had lots of seals replaced to try to fix the problem.
-cam seals
-cas o ring
-new but seemed kinda crappy valve cover gasket
-front crank seal

are the oil cooler/filter mounts known to leak?

I have no idea where else it might leak My last resort is to just pull the transmission and replace the rear crank seal, but I have some UV oil additive that I should try to find where its coming from but the stuff isnt much help usually.

From reference on the ground, is it driver or passenger side? Front ? Rear?

I would brake clean as much as possible top to bottom. Drive around some more then inspect again from top to bottom. If it's dry up top the issue may be lower :2cents:

I was chasing oil leaks not long ago and it turned out to be cam & crank seals. Was happy to find it wasn't the oil pan itself. Which reminds me.... I should double check it today :eek3: I haven't in a while since the fix :eggplant:

THanks thats a very good idea and one i didnt do because i just assumed it was the rear crank seal and was waiting to do clutch and a seal.
The oil pan doesn't look too hard except doing it on jackstands might make the subframe removal a bit harder!

BTW What is the eggplant?

I would check the following 2 places:

1)near the oil filter area (where you have already suspected it). There is an oil seal behind the whole oil filter housing that may leak over time. its a cheap seal and probably wouldn't hurt to change it out next oil change since you've already changed out mostly every other seal. When you take off the oil filter, theres a 24mm nut (iirc, that's the size), you take that off, take off the housing, and youll see the seal there.

2)near the power steering/oil pan bolt area. There is a bolt that holds the power steering bracket to the block. its also responsible for holding the oil pump in place.


Keep in mind, you may have already fixed the leak, and there may be residual oil still in places that is gravitationally falling, but other than the rear crank seal and the above 2, not sure where else to look.

Usually doing the oil pan the entire motor comes out of the top. But I've heard some people say they can do both in the same amount of time :dunno:

Attachment 231978

I found a video of this jerkass who thinks he owns my car and yours. he pulled the pan without removing the engine by dropping the subframe it looks pretty easy I have never pulled a miata motor just stripped it down to replace a head gasket. I think this looks easier than disconnecting all the engine crap. But don't really know.


Here is some baba ganoush which has eggplant in it. am i doing this right?

https://www.miataturbo.net/attachmen...ine=1460755760

Not pulling the motor means you need to brace the whole thing using one of those nasty across the shock tower engine stands. If anything slips, it's going to be a LOT more inconvenient than disconnecting them by hand... what with the soldering, crimping, running new wires, hoses, lines, etc. etc... if you're alive to even worry about it.

Edit: I'd only use one of those if I was just changing the subframe/control arms (which I did, when I put in my 99 parts)

dude in video just used a steel tube and wood and chain

It's your car and your life. Do whatever makes you feel good. I wouldn't get under an engine suspended by a piece of pipe, some chain, and some 2x4's if you were paying me, and I'd never let my car have that done to it if I could avoid it.

When I did the subframe swap (on a lift) I set the engine and trans on high lift jack stands at the beefiest looking points along with the proper engine fender hoist.

It's not easier. Pull the motor.

And Jspeed it's the AC bracket down there, not the PS pump bracket.

Anyone know what size the stock bolt is in case i find it missing? My car still has factory AC.

M8x1.25x45mm for the AC bracket.

Take some pictures of the front, it's pretty obvious if it's missing. I've also seen a fair number of oil filter stand o-rings leaking on even 100k motors, so you could start there before pulling the engine for the oil pan.

Yes! definitley going to do the simple things before the drastic lengthy repair. Thanks for your help.:likecat:

This is the size bolt for keeping the AC? I read somewhere someone suggesting this size is for when deleting the AC.

I cleaned around the area. Ac compressor was pretty oily and the bottom tray was oily and nasty on the exhaust side right under the compressor so it makes me think I am in the right area for the oil leak.

I found the bolt and it appears ok and to be tightened up well. Does it look normal? Should there be a split washer or spacer between the bolt and the engine?

https://www.miataturbo.net/attachmen...ine=1460840811

Here is a bottom view showing grot and the bolt.

https://www.miataturbo.net/attachmen...ine=1460840811




https://www.miataturbo.net/attachmen...ine=1460840811

There's a sliding spacer there to make up any difference in casting, that's all that is. Have you don't a water pump and timing belt job recently? That should include the front main seal and is the first thing I'd replace for a leak on that area.

I replaced the front main seal a while ago maybe a year. All the sludgy oil might be from before I did that. I should have cleaned... I have replaced the timing belt but not the water pump It seems to be working fine and no leaks.
I figured I would eliminate the valve cover leaking so I busted that off and re did the RTV and added some UV oil additive.

Went out tonight with my black light and could not find any leaking anywhere will drive more and report back. I scrutinized the oil cooler and the oil pump area near the ac compressor and not a sign of UV dye.