sbefar01

Changed my oil using the local shop i know well, they put in 9 QTS. I am now pouring smoke out the pipe. I called Porsche they said to put in 8.5 qts then check and maybe go to 9 qts. Can a 1/2 Qt overfill cause a lot of oil burn/ smoke or could it be some other oil change mishap. The car was running fine before and even when it was drained it was down to near 3 qts. (i had just bought car).

Macster

Maybe. I've never overfilled my Turbo (or my Boxster) with oil so I can't say for sure.

Just a head's up. While you were told maybe 9 quarts went in the shop may not know just how much oil went in the engine. If someone there overfilled the engine with oil at all I have no confidence in whatever the shop tells you.

My course of action would be to have the oil drained and replaced along with the filter just like a regular oil change but this time the shop should be *darn* sure to not overfill.

There's a specific series of steps to follow in a Turbo oil change that involves (skipping some details) draining the engine (crankcase, oil tank, turbo oil collectors) of oil, removing the oil filter and replacing it, and adding in a specific amount of oil and even waiting a while after adding oil before starting the engine.

The shop manual calls for (IIRC) 7.8l of oil which works out to around 8.25 quarts. After adding this much oil the oil level check -- once the engine is warm enough to let this happen -- should show the oil level at the max bar, not above and not below this line.

If you want to skip the full drain/refill procedure the crankcase drain can be opened and the oil drained from this. The amount of oil that drains based on my experience -- but I've never bothered to accurately measure this -- is several quarts. You'll have to catch the oil in a pan and measure the amount of oil you collect and then add that amount minus the quart or whatever amount over you suspect was in the engine.

Then next time consider using a shop that knows what it is doing and can do it right.

Sincerely,

Macster.

sbefar01

I see, this makes sense. So are there multiple areas that need to be drained bc i only saw him drain 1 area as I was standing right there. thx. Oh man another $100 in oil, i need to go to a better shop.

neanicu

It sounds fishy...are you sure he drained all the plugs?(2 Turbo,Crankcase and Oil Tank)?
Because if he didn't...there's your overfill...
Most important-you haven't mentioned anything whether you checked the oil level when warmed up? What's it showing?

sbefar01

I had my friend (ASE certified) take a look, he agrees with you guys that ONLY the crankcase plug was drained in all likelihood. My friend drained out close to 5 qts so far total, the black old oil was still there and came out first. The lighter colored oil started to come out a touch and that's when we plugged it back up; in 2 phases. We did -2 QTS then circulated the oil with a quick spin around the block, then -3 QTS more. Its much better now, still not perfect, but i am bringing it back to the shop and having them pay for all new oil and have them do it properly. Thx guys.

adam_

IMO the turbos dont need to be drained if you do regular oil changes- just drain the tank and the crankcase..

Not sure about this two phase stuff... I've have simply DONE AN OIL CHANGE. The oil all intermingled, it is now a mixture of old and new.
Drain
Fill
Done

SSST

i think this may explain the problem.

There are 4 drain points on the turbo. Oil tank, crank case, and each turbo. The turbos only hold about half a cup each. If either the crank case or oil tank were not drained then you have way too much oil in your engine.

Also, since the shop obviously doesn't work on Porsches much, they probably don't have the crush washers you need when you reinstal the plugs. Not replacing the crush washers will likely result in dripping oil.

I'd get my money back and find a shop that knows Porsches.

Macster

Agree. Now that the full story is coming to light it looks like some fresh oil was added to who knows how much old oil.

A full oil/filter service in this case is called for to drain the engine and tank of the mixture of old and new oil, and then of course make sure the engine is refilled with the proper type and amount of fresh oil.

The techs tell me they do not drain the turbo oil collectors but when I do my oil changes I like to do this. While not much oil comes out -- a cup is being generous based on my observation -- the techs tell me that seeing that some oil comes out and that about the same amount comes out of both drain holes is worth seeing.

Not sure what's the deal if the two drains do not produce the same amount of oil.

Sincerely,

Macster.

XR4Tim

As a tech, I always drained the turbos, as per the workshop manual. No reason to be lazy when someone's paying you to do it right. One advantage, is you will be able to see if bearing material shows up in the turbo's oil drain it could be an early indication of a failing turbo.

Dock

I always drain the turbos.

sbefar01

Well, the shop fixed most of the issue, they drained all of it again except the 1 turbo, stating that it looked like it had "never been touched before and they didnt want to crack the 1 turbo collector". All new 9qts was put in to the proper level indicated on dash. They cleaned out all the dripping overflow and did a full flush. They cleaned the intake pipes, air filter and assembly and checked for other leakages, observing that most of the oil had leaked out through the vents. The new oil filter that was put in the 1st time around remained IN, i didnt think to replace the oil filter all over again bc of 30 min of driving on mixed old and new oil. The crush washers, i didnt know about this . . . . . . However, the car is running very good, no smoking now, very smooth operation I will bring to dealer just for a quick look and ask about the crush washer scenario so i dont leak anything. Let me know if I missed anything. Thx guys!!

Dan87951

Man sorry to hear about your issues. This is exactly why I work on my own cars! Man can't imagine the crankcase pressure with that much oil overfilled.

Macster

FYI, those are not crush washers, per se, but sealing rings. They should not be reused.

The techs tell me when they get a car in with most often an oil seep around the sump drain plug or some other drain plug/drain hole seal, it is because the owner insists on reusing the 'crush washer'.

The sealing ring is the sacrificial item in the critical drain plug/sump/tank/crankcase drain.

Sincerely,

Macster.

Macster

No additional crankcase pressure resulted. Still the overfill was not a good thing, but probably no real harm was done. The scavage pumps remove any oil and keep the crankcase relatively 'dry', as it should be with a dry sump oil system.

The extra oil simply accumulates in the oil tank and renders the oil separation baffling non-functional. One side effect is the engine is fed crankcase fumes with a very high level of oil (as vapor) in it.

If anything was really at risk it was the O2 sensors and the converters, especially if the oil has a high level of zinc or some other 'anti-friction' or 'anti-scuff' additive in it. These in the heat of combustion/exhaust gases melt and coat the sensor tips and the working surfaces of the converter and can negatively affect their functionality.

Sincerely,

Macster.

sbefar01

Well . . . . . . . does anyone know how to install diverter valves? Thought I was in the clear! I got a check engine light, brought it to the dealer and the diverter valves were bad bc of the overfill. I just ordered the upgraded Agency Diverter Valve pair since i was going to do that anyways for the Softronic/EPL upgrade in the winter. My friend is an ASE Certified mechanic but i would like to give him some pointers on the diverter install. Thx again for all your assistance and
wisdom

And yes Macster thank you for the boost of confidence that the crankcase pressure most likely didnt result in a damages/no CEL until until proper fill level was attained ironically.