RMS Leak - but where did the oil go?? So confused..

Hi all,

I have a 2005 987 Base 2.7. For the last 11 months I had an RMS leak.

Drops a few drops of oil on the driveway everyday. (going to fix it when i change the cluth one day)

When this start about 11 months ago, i did my own oil change and over filled it to the top segamant probably either .5 - 1 full extra liter of oil by mistake.

I go and check the oild for the last few days and its still overfilled on the indicator after leaking all this oil everyday?

How on earth is this possible? I was anticipating having to top up?

Please shed some light on my confusion??!!?

Thanks!

Quote
porschestar
Hi all,

I have a 2005 987 Base 2.7. For the last 11 months I had an RMS leak.

Drops a few drops of oil on the driveway everyday. (going to fix it when i change the cluth one day)

When this start about 11 months ago, i did my own oil change and over filled it to the top segamant probably either .5 - 1 full extra liter of oil by mistake.

I go and check the oild for the last few days and its still overfilled on the indicator after leaking all this oil everyday?

How on earth is this possible? I was anticipating having to top up?

Please shed some light on my confusion??!!?

Thanks!

but I've never come across anyone who has had to top up engine oil due to the oil loss from an RMS leak. When I first discovered my 02 Boxster had an RMS leak it was just before a long awaited road trip. I checked with the SM at the dealership and he told me it was ok to drive the car, he had never heard of an RMS causing anything more than a bit of a oil stain on the garage floor.I drove all over heck and back (approx. 8K miles) and never had any issues with oil loss.

The only way that excess oil in the engine is going to get out of the engine is by way of vapor routed by the AOS to the engine unless your car's engine consumes a bit of oil.

Next time you change the oil do not overfill the engine with oil.

Also, is there any chance that the RMS is leaking because I overfilled the oil with .5 to 1 litre of oil?

Thanks

overfilled the engine with oil you can only guess by how much. The oil e-level system is not intended, can't show you how much extra oil there is in the engine only that the level is above the max. line which it should not be.

So I can't say. You may have put so much oil in the engine the RMS may be under water, so to speak, and the leak could be much more severe compared to the same engine not overfilled with oil.

My experience with my 02 and its leaky RMS was the thing only spotted the garage floor after I left the car parked unused for 9 or 10 days while I was out of town in my other car. Before or after this period of no use the RMS left no spot anywhere else. The leak was quite small. But as I touched upon above had the engine been overfilled with oil the leak might have been much worse.

brings more sitting oil to the level of the seal. So that makes some degree of sense, yes.

No experience one way or the other.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

1. the RMS leak is a tiny amount of oil. It would take years to lose a quart

2. over-filling can be as bad or worse than being low. It causes the crankshaft to slap the oil and aerate it, causing possible foaming and therefore lower volume flow and film strength reduction. Bad at high rpm. probably just a fuel waste at lower rpm.

conclusion: don;t over fill, and dont worry about the RMS. yes, fix it when the flywheel is off next.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

I wouldn't even be so sure you are overfilled. Every single time I've had the oil changed on my Cayman -- which is now about 5 or 6 times in 4 years/16K miles, we have measured out what we put in according to the manual, and every single time it shows overfilled. Mechanic sez not to worry, and I have neither clouds of oil in my exhaust, drops in my garage, nor does the level ever drop below overfilled. In fact, I'd tend to believe the gauge doesn't even work except for the fact that one time we "only" put 7 quarts in it, and then it showed about half full, so we added the rest and voila! overfilled again. They replaced a perfectly serviceable dipstick with a crappy piece of electronics that might or might not even work. Well, hopefully I don't have a problem because my warranty expires this month. Yeah, I could take it to the Porsche dealer to inspect ... that's the Porsche dealer who sold me the car with "rust" on the wheels that they wanted to repaint and it turned out to be cosmoline. This kind of thing, together with the IMS and the clunking when reversing in cold weather and the fact that tall people can hit their heads on the roll bar in a 986 Boxster, are why it kind of makes me puke when I hear the fanboys talking about how great Porsche engineering. From personal observations ... the car is no better than mostly okay.

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paulwdenton
I wouldn't even be so sure you are overfilled. Every single time I've had the oil changed on my Cayman -- which is now about 5 or 6 times in 4 years/16K miles, we have measured out what we put in according to the manual, and every single time it shows overfilled. Mechanic sez not to worry, and I have neither clouds of oil in my exhaust, drops in my garage, nor does the level ever drop below overfilled. In fact, I'd tend to believe the gauge doesn't even work except for the fact that one time we "only" put 7 quarts in it, and then it showed about half full, so we added the rest and voila! overfilled again. They replaced a perfectly serviceable dipstick with a crappy piece of electronics that might or might not even work. Well, hopefully I don't have a problem because my warranty expires this month. Yeah, I could take it to the Porsche dealer to inspect ... that's the Porsche dealer who sold me the car with "rust" on the wheels that they wanted to repaint and it turned out to be cosmoline. This kind of thing, together with the IMS and the clunking when reversing in cold weather and the fact that tall people can hit their heads on the roll bar in a 986 Boxster, are why it kind of makes me puke when I hear the fanboys talking about how great Porsche engineering. From personal observations ... the car is no better than mostly okay.

who do not know the correct amount of oil to put into the engine. The amount in the owners manual is not always the right amount. The correct amount of oil is based on the VIN.

It is also based on the engine being up to at least 70C and with a drain time of 20 minutes if a pre-DFI engine, or one hour if a DFI engine. There is also a refill amount based on an overnight drain period.

The specified amount of oil is added to the engine and then the oil level is checked with the oil e-level system. If this does not show the correct reading based on the fact a known amount of oil was added to the engine and the level checked in the correct manner, the oil e-level system is malfunctioning.

Adding oil then checking the level until the level is "right" is wrong. Wrong. Wrong.

BTW, your comment: "one time we "only" put 7 quarts in it, and then it showed about half full, so we added the rest and voila! overfilled again." suggests to me neither you or your mechanic know how to read or interpret the oil e-level display.

The oil level sensor is only intended to measure the uppermost (IIRC) 1.5 liters of oil. Each bar represents 1/4 liter, though the number of bars might have changed at some point in the newer models and in this case then each bar represents a volume of oil different possibly than 1/4 liter.

While the owners manual can't be counted on to have the correct amount of oil for a proper refill listed it does cover the oil e-level readout. So consult the owners manual.

So, if you added 7 quarts and the level was just half the number of bars up on the display the level was down around a quart or so. But as I covered above neither you or the mechanic know how to properly fill the engine with oil.

"The amount in the owners manual is not always the right amount. The correct amount of oil is based on the VIN." Then you say the problem is not the oil level system but me and my mechanic.

Unbelievable. Not enough to correct me but actually my fault? Very impressive. First time I've ever been flamed for doing exactly what the &$**# owner's manual said to do!

Apparently your car came with the magic Ouija board that provided your information. This of course is also my fault because I forgot to check the option for the $700 Porsche Ouija board in leather with deviating stitching when I bought the car. Regardless, I would say the real problem is an absolutely IDIOTIC company that would sell a car with bad information in its owner's manual. WTH kind of car is it that you can't even rely on what's in the *#@&* owner's manual? That is, of course, assuming you are right and the manual is wrong. Oh, I'm not even doubting you. You may well be right. Or, the manual may be right. Who knows? How the heck do you trust anything on the *#&@ car if you can't even trust the *#*( manual. Of course, if I follow the manual and the engine blows up, that will be my fault and naturally they won't cover it, because that's just the nature of the company and everyone apparently knows that but me. Now I'm impressed even more with Porsche engineering.

It also states to fill per the gauge.

It also states to measure oil level at operating temperature. i've noted before this is the only possible accurate method. Otherwise they would need graphs of volume by the temperature of your garage...

The number that is occasionally inconsistent is the capacities page. Apparently it the actual capacity of the sump change based on manufacturing differences. I didn't know that, but it does make sense. I have seen lots of people fill to the brim cold, and then have to drain over-fill out. Not really a fun task.

I do prefer the old method of the dipstick, but its great to have something that checks one's oil every morning, and at the track, before every run (assuming its level).

So Marc's actually correct, and aside from the removal of the dipstick, the system works very well. Better than i would have ever imagined.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

Indeed it does, and so what? According to my manual (Page 188), the procedure you describe is for "Topping Off" engine oil. Of course I would follow the "Topping Off" procedure if I was, you know, topping off the oil. But I wasn't topping off the oil. I never needed to. My car was delivered brand new from the dealer with the gauge showing (as I know now) overfull. Me, I just assumed the dealer and my highly experienced mechanic were doing it right and that this was a normal condition. And it has never dropped below the level of "overfill" in 16,000 miles of ownership and 5 oil changes. No reason to "top off" anything.

In all my oil changes after taking delivery, I actually thought I was supposed to follow the section on "Oil Change" at Page 190 since I was, after all, actually changing the oil. Now when I look at that section of the manual, it doesn't say, "Follow the procedures for topping off." Nor does it say "fill to the gauge." Nope, it says, "Please see the chapter "CAPACITIES" on Page 273." Now perhaps I do not understand the English language but that instruction seems pretty clear to me, and it's also consistent with every other car I've ever owned. They tell you to see the section on CAPACITIES so you take out the old oil, drain it good, and fill it with the exact amount recommended in the section on CAPACITIES. Duh! Why would I top anything off when I was carefully measuring and putting the correct amount of oil into the engine in the first place? All I did was follow what the manual said to do, and now you people tell me that I'm wrong??? The only thing I did that was wrong was trust the manual, because apparently the idiots who wrote the stupid manual got the CAPACITIES wrong. But that doesn't make it my fault. It's the engineering geniuses at Porsche who can't get capacities right, or apparently, write the procedures correctly, either.

Sheesh!

but it does direct you to the dealer for this info. The dealer should be your source of info regarding these cars.

Porsche is a bit cheap in not keeping the manual up to date. It still has some wrong info about oil too which causes no end of confusion. Trouble is if Porsche makes a mid-model change that changes the oil level or anything else that was covered in the previous manuals then it has to have an updated owners manual printed up and stocked.

OTOH, Porsche apparently doesn't believe these cars are really owner serviceable. It doesn't help that Porsche is among all carmakers the most close mouthed one regarding the inner workings of its DME (I can't even buy this info from Porsche) and other controllers, engine measurements and so on.

It is too late now but if you received the car with too much oil in the engine you should have insisted the excess be removed. However, it is understandable that this was probably the last thing on your mind when you received your new car. And it doesn't speak very well of the dealer to deliver the car with the engine overfilled with oil. It is a rather simple job for a tech to remove the excess oil.

I've covered before my feelings on the dipstick and I won't bother to repeat it now but its banishment from a modern engine is long overdue.

My manual refers me to the "Capacities" section of the manual, not to the dealer, and nowhere does it say to consult the VIN to get this info. In fact, in 4 years of ownership, this is the first time I have heard of such a thing. Where did you dig it up? And as for the car being delivered overfull, I thought that was a normal condition. How was I to know otherwise? As I recall, my 986 Boxster that I had only briefly (due to the tall guy -roll bar issue) was also delivered (used but serviced) from the same dealer and was also was overfull according to the gauge. That was the same dealer that wanted to repaint my brand new Cayman's wheels to get rid of the cosmoline. So far, I see an idiot dealer and a sloppy company that hides necessary information. Or not -- at this point do I believe you, or my manual and a highly experienced Porsche mechanic? And you guys act like I'm an idiot for not knowing this stuff?

The 981 owner's manual states 19" winter tires require 32 psi (at 68º F*.) The TPMS parameters are currently set for these tires, yet when a reading displays 33 psi, the fill info field shows +3 psi, which means the system wants 30 psi, not 32. An aside, I don't like that the system can't read 31 psi, so it sometimes flits between 30 and 32-- not very precise. I use a Moroso dial gauge for the critical pressure setting.
* Although the manual gives the science-based "standard" temperature, I don't see an issue with setting pressures based on whatever the ambient temperature is.

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paulwdenton
My manual refers me to the "Capacities" section of the manual, not to the dealer, and nowhere does it say to consult the VIN to get this info. In fact, in 4 years of ownership, this is the first time I have heard of such a thing. Where did you dig it up? And as for the car being delivered overfull, I thought that was a normal condition. How was I to know otherwise? As I recall, my 986 Boxster that I had only briefly (due to the tall guy -roll bar issue) was also delivered (used but serviced) from the same dealer and was also was overfull according to the gauge. That was the same dealer that wanted to repaint my brand new Cayman's wheels to get rid of the cosmoline. So far, I see an idiot dealer and a sloppy company that hides necessary information. Or not -- at this point do I believe you, or my manual and a highly experienced Porsche mechanic? And you guys act like I'm an idiot for not knowing this stuff?

The first line under the section title says: "Use only fluids and fuels authorized by Porsche. Your authorized Porsche dealer will gladly advise you."

Under this comes the capacities for the engine, coolant, and so on.

Every capacity is prefaced with "approx".

While it is not crystal clear it does strongly suggest that to eliminate the "approx." from the capacity a consultation with the dealer is advised. A long time ago the parts manager at the dealer where I bought my 1st Porsche told me parts, fluid capacities, even batteries, everything for the car was tied to its VIN.

As for the highly experienced Porsche mechanic this is in conflict with what you related about the oil after a change being over filled. The engine oil should not be overfilled. That that the dealer let the car go out like this was wrong. But if I read your post correctly that your experienced mechanic then repeats this error upon every oil change clearly indicates he is not experienced with these newer models.

As I have posted before the correct oil change procedure has the engine up to some temp, the oil drained for some specific amount of time (20 minutes for pre DFI engines, 1 hour for DFI engines, or overnight for either engine) and Porsche has specific refill amounts for each drain interval and these amounts are tied to the VIN. In this case the amounts are not prefaced with approx. but are given to either tenths of a liter or possibly even hundredths of a liter.

The oil dispensing guns at the dealership display the amount of oil dispensed in 1/100ths a liter. (I wish I had the presence of mind to take a pic of one the tech showed me as he was filling an engine with oil.) The tech adds the exact amount of oil and notes the oil e-level display reads what it is supposed to. For example in the case of my 996 7.8l of oil is added and as soon as the engine/oil is hot enough to check (the engine has to be running at idle, up to temp, and the car level) the oil e-level gage oil level should be at the max. line. Not below and certainly not above.

Not to put to fine a point on it you relied upon a mechanic for properly servicing your vehicle, but it appears you picked one that is not up to speed on these newer cars. The dealership mechanics get a week or two of training per new model just to cover the basics and differences of the new models. It is hard to believe anyone that doesn't get this same training can be anywhere near as good at servicing these vehicles.

It was not my intention to make it sound like you were an idiot for not knowing some of the above. If my responses came across that way I apologize.

I'm not so sure overfilling is that bad. I overfill my motor by close to a quart ( I would rather have a cloud of smoke from an overwhelmed AOS than a spun bearing because of oil starvation) when going out on the track and with the motor idling, the oil level didn't even register on the dipstick, so I'm a little sceptical that a quart overfill will let the crank slap and earate the oil.

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San Rensho
I'm not so sure overfilling is that bad. I overfill my motor by close to a quart ( I would rather have a cloud of smoke from an overwhelmed AOS than a spun bearing because of oil starvation) when going out on the track and with the motor idling, the oil level didn't even register on the dipstick, so I'm a little sceptical that a quart overfill will let the crank slap and earate the oil.

increase the oil's air content and bearings could suffer because of it.

Whether a bearing fails because the oil system is unable to supply enough oil or because the oil it supplies is overly aerated is immaterial.

The dipstick is not intended to measure the oil level while the engine is running. The oil level is approx a quart low when the engine is running at idle the missing oil is in the oil galleys and in/under the camshaft covers and in other areas inside the engine. A considerable amount of this oil is in vapor form at higher rpms.

The oil vapor processing efficiency could be compromised by the engine being overfilled with oil -- the techs tell me this is so -- which brings with it at least two problems: 1) More oil is in vapor form which works to lower the effective oil level; 2) The oil vapor is not processed as efficiently as it would be otherwise and the oil vapor laden crankcase fumes are routed to the engine during hard driving.

Oil in the combustion chamber compromises the premium gasoline's ability to resist detonation. So even though the engine controller will retard the spark timing the spark timing adjustment when detonation is detected its adjustment is based upon the expectation of the gasoline and its octane rating. The timing adjustment doesn't have a large range of adjustment and if this adjustment limit is reached if this is not enough to eliminate the detonation... BTW, detonation is a silent engine killer.

As long as the oil level is at the max. line when the engine is hot and the car level, the oil is reasonably fresh (contaminated oil foams more readily), and of the right type and viscosity there is no need to overfill the engine. If the oil does or does not meet the above requirements overfilling the engine with oil is just doing the wrong thing for the wrong reason.

They don't state int he manual: "fill to the mark, or one or two quarts more if you like".

we can safely assume its the best level to balance supply with slap and aeration. It is a quite real phenomenon, although icant prove that it occurs at + 0.5 qt or + 0.75 or....

nonetheless i would follow the manufacturer's suggestion, as close as is practical. In reality we may be +/- 0.25 qt

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

Overfilling--The 986, IIRC, had a 9 qt oil change with filter; the 987.1 used 8 qts. on the oil change with filter.
I had an indy make a mistake with an overfill by not checking the differences on our 987 vs. the 986. The oil level was clearly above the the full level when I looked at the electronic measuring mode when the car was sitting before I drove off and I just happened to ask how many qts he put in--lucky for me.

Measuring on a level surface--I found out how sensitive this is one day with the 987 when I changed it's spot in a 3 car garage.
In the center-spot (after a dealer oil change) the indicator was at the full level .A few weeks later, I moved it to an outside spot and it hit the overfill mark when I checked the oil level. Knowing the oil level had not been added to in the few weeks since the change I got a level out to check the slope of the floor below the sump and yep, there was slight grade front to back and from the side to center--probably for the water to flow to the drain.
Make sure you're on a level floor before you measure.

Hot oil removes much of the water content that might otherwise have been absorbed as the oil cooled.

AOS that then takes -- with the help of low pressure courtesy of the AOS's connection to the intake manifold -- the crankcase fumes with its load of water vapor and oil vapor separates the oil vapor from the fumes and returns this now in the form of liquid to the crankcase and eventually the oil sump while then routing what remains of the crankcase fumes to the engine's intake tract.

Perhaps it's been held over from pre-AOS days as an added precaution or augmented accuracy.

boil off fuel, water, and other light contaminants. While oil may only average, say 175 deg (F), i am confident that as it circulates it gets well above that and gives off steam, which is eventually EGR'd (AOS'd).

in fact, i believe that failure to do this results in water and fuel contamination, corrosion, oil film weakness, and leads to many of the failures we talk about. fresh, clean, basic (as in not acid) oil is crucial. Fresh, acid, diluted oil is death. note both can be fresh.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com



Edited 1 time(s). Last edit at 02/13/2013 11:15AM by grant. (view changes)

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grant
boil off fuel, water, and other light contaminants. While oil may only average, say 175 deg (F), i am confident that as it circulates it gets well above that and gives off steam, which is eventually EGR'd (AOS'd).

in fact, i believe that failure to do this results in water and fuel contamination, corrosion, oil film weakness, and leads to many of the failures we talk about. fresh, clean, basic (as in not acid) oil is crucial. Fresh, acid, diluted oil is death. note both can be fresh.

Grant

this is not sufficient to ensure the water vapor is removed from the oil. While the water may boil out of the oil as soon as it encounters cooler surfaces it will condense and fall back into the oil.

The entire load of oil must get hot enough to boil the water out of the oil and the water vapor's path to to the AOS must be direct enough and be warm enough that the water doesn't condense on the same walls that collect the oil from the oil vapor and both run back down into the crankcase.

Now the water is helped by low pressure that is maintained by the AOS. Thus the water boils at a lower temperature and will remain in a vapor form at a lower temperature.

Is that oil rarely gets above 175F, say, in my Audi.

It only got to just over 200F on the track.

Yet my track used cars always have vanishingly low dilution of all kinds when tested, while street chariots have a normal amount (0.5-1.2%)

Grant

Grant

gee-lenahan-at-gee-mail-dot-com