993 turbo valve covers

993 turbo valve covers

Author
Discussion

ThirstyMoose

Original Poster:

86 posts

161 months

Sunday 12th April 2015
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Hello all,
I'm beginning to see some weeping oil from the valve covers on my turbo. I'm considering replacing all four covers and curing the issue once and for all. Has anyone done this job on a turbo? Do you recommend the billet covers or oem? Is it diy or specialist. If specialist how much is considered going rate?

Any help/advice gratefully received!

Cheers

Thirsty

Jevvy

232 posts

170 months

Sunday 12th April 2015
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Why not just replace the rubber gaskets and hardware instead of the full covers? The covers are plastic so dont warp like the earlier covers so should be very much re-usable. I dont think there are turbo billet lower covers as they dont have spark plug holes and the standard turbo lower covers have small cutouts to make room for the turbos and heat shields etc. Lots to remove to get to the lower covers so be prepared for some 'while yr in there' stuff.

mark.c

1,090 posts

181 months

Monday 13th April 2015
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Thirsty, below is my reply quoted from 911UK in case you missed it.

As said above, definately a job with scope for 'while you're there'

Quote

In the interest of balance I have billet ones on mine and know of three Turbos who have run these for many years ( one for nearly ten years and 40k)with no adverse effects whatsoever. Each to their own of course and once they are off then the choice is yours. Mine leaked at a relatively low mileage so took the opportunity to try something other than plastic. I don't think Porsche made them from plastic for any particular engineering gain.

As for the job, if everything goes smoothly then it's not too bad, in my case I couldn't 'unknow' things I found along the way so the job developed some mission creep as these things tend to do. All tubo nuts and bolts, gaskets, heat shields etc got replaced, also found some small cracks in the welds of the manifolds so they came off to be repaired properly. Both turbo oil pipelines were seeping so they got replaced too...both boost pipes looked a bit chatty so new there too...oh and I also took the rear PU off as the brackets were a bit scabby, so whilst that was off it would be foolhardy to not check the chassis legs, no rust at all thankfully but took the opportunity to drown them in Bilth Hamber etc etc....you get the idea!!

I don't run the lower drip tray for what it's worth. Off the top of my head all the mission creep extras, including having the manifolds repaired came to about £1500, some of the prices actually made me laugh/cry at how ridiculously expensive they were but if it's worth doing right and all that.

ETA: For clarity the £1500 was purely for the extras found along the way, parts only.

Edited by mark.c on Monday 13th April 13:37

Orangecurry

7,430 posts

207 months

Monday 13th April 2015
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I don't think the 'issue can be cured once and for all'.

The material that the covers are made from is of no importance - they are cosmetic only - the issue is that the rubber gaskets between casing-cover go hard over time/use/heat-cycles, and will need replacing every 'n' years/miles.

I observed a slight weeping start from one of my lower gaskets - I replaced only the rubber (and the awful chocolate-headed OE hex-bolts), and it has been fine since.

Nurburgsingh

5,122 posts

239 months

Monday 13th April 2015
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Mine, all be it on a C2 not turbo, were weeping from a small crack that had formed around one of the fixings...

I started looking at the options and got 'Jackal'd " and ended up with the billet items.

ThirstyMoose

Original Poster:

86 posts

161 months

Monday 13th April 2015
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Thanks guys, I'm considering my options, but it looks like oem covers. Possibly fit myself, but waiting for a quote from local specialist (Precision).


Orangecurry

7,430 posts

207 months

Monday 13th April 2015
quotequote all
I know nothing about the differences between cooking and turbo engines, but assume they both have the same INA hydraulic lifters? I would consider changing these 'whilst you are in there' if they have not been done.

Again the issue here is rubber - a small rubber sealing ring on each 'tappet' can harden/perish/detach.

'Consider' as yours might be fine and last until the next cam-cover gasket change.