Oil Leak from engine bay

[zcacogp]

Guys, 

 

Small but annoying one here. 

My 987.1 2.7 Cayman had a note of 'slight oil leak' at a recent MOT. It was annoying, in part simply because I hadn't noticed it as I haven't used the car much. 

So I jacked it up and had a look. Firstly, the oil filter housing wasn't screwed all the way home which explained some of the leak. But there was also a noticeably oily pipe in the top of the engine bay. Here's a photo viewed from underneath. 

When viewed from above it seems to be this pipe. 

 

For reference, this is stamped with part number "987 107 064 01" and a brief google search suggests that it may be part of the AOS. 

Having tightened up the oil filter the oil level is still dropping slightly (a recent 350-mile trip caused one bar drop on the dashboard gauge) so I presume that the problem is still there. 

Has anyone any experience with this? Is this pipe a regular candidate for causing problems? Or is it likely to be something else? 

All advice welcomed, thanks. 

 

Edited March 28, 2022 by zcacogp
Making the links to images work correctly

[iborguk]

Has the AOS on the car ever been replaced ?

Any white smoke at startup ? 

[zcacogp]

iborguk, 

Thanks. I'm not aware that the AOS has ever been replaced (115,000 miles, late 2007 model) but I don't have quite as comprehensive a set of service history as I would like. 

White smoke at startup only after a short journey, which I am told is normal. Given that it only does infrequent but long journeys nowadays then I've not seen it smoke for a year or more. 

[iborguk]

Can you get the oil cap off with the engine running ? If you can't or it's difficult to remove then that's one indicator the AOS is on the way out (excessive vacuum prevents the oil cap being easy to release)

 

Edited March 28, 2022 by iborguk

[zcacogp]

Thanks again Iborg. 

Would a failing AOS explain the oil loss and the damp seen on the pipe? 

I'll try to remove the cap when it's running tomorrow. Does it make any difference whether it's done with the engine hot or cold? I presume not. 

[iborguk]

Just now, zcacogp said:

Thanks again Iborg. 

Would a failing AOS explain the oil loss and the damp seen on the pipe? 

I'll try to remove the cap when it's running tomorrow. Does it make any difference whether it's done with the engine hot or cold? I presume not. 

It's something to rule out, the AOS is almost a "consumable". I had one go at around 35k miles, with no symptoms (smoke or leak).

Don't think it makes a difference re the cap test, try it from cold.

Beyond that suggest get it to someone to investigate the leak further.

Good luck getting it sorted.

[iborguk]

 

 

[zcacogp]

IBorguk, 

Thanks again for your help, and for sending over the instructions on how to change the AOS. 

I've just started the old girl and the oil filler cap is easy to remove with the engine running; there appears to be little or no suction holding it on. Maybe the AOS is OK after all and the leak is coincidental. Either way, I'm in a bit of a quandary as to what to do ... investigate more I guess! 

Thanks again. 

[iborguk]

Yup - worth spending a bit of money to get it to someone who can help you dig further on it methinks.

Good luck.

 

[zcacogp]

Yes. Downside of that otherwise excellent plan is that it's already put a £300 dent in my wallet this month! Some new oil poured in once in a while will be the solution for the next couple of months in order to keep the Household Exchequer happy. 

[iborguk]

Ouch and sounds a reasonable holding plan until funding approval allows 👍