Re: RMS oil leak after winter storage

As I live in Southern Ontario Canada I store my 07 Boxster during the winter months. For the past 3 years, immediately after the initial engine start in the spring, oil leaks from the Rear Main engine seal. This is an expensive repair that I do not wish to have done every year. I believe that because the engine is not being run for 3-4 months the RMS is dry and without lubrication. Thus at startup the torque from the crankshaft tears the seal. The engine oil is changed before storage and I was wondering if there is an additive could be added to the oil that would prevent this RMS from drying up.

My service shop has suggested starting the engine regularly while it is storage.

Looking for a solution.

Thank you in advance for any suggestions



Edited 1 time(s). Last edit at 10/31/2017 10:39PM by imtonyd. (view changes)

I don't have an answer for you. I'm also in southern Ontario. I never had that problem with my 06 Boxster in the 7 years / 108,000 km I had it. Like you, I would change the oil shortly before storing it. It was usually stored for 4 months December - March.

I never started the engine while it was in storage. At start up you get the most wear and tear and also get the most fuel mixed with the oil.

What type of oil are you using? I stuck with Mobil 1 0W - 40.

Hi Guenter

Thanks for you reply.

I have been using Castrol edge synthetic 5w40

You do not mention how much oil is leaked; a drop? a few drops? You could always try 5W50 and see what happens. here is a list of Porsche Approved oils from Pedros Garage site.

[pedrosgarage.com]

Hi Carlos

Whenever I park the car I see a couple of oil droplets the size of 2 dimes

Thanks for reply and the link to the list of Porsche Approved oils.

Many cars sit (which is generally not a good thing) without developing RMS leaks.

From what i have read and heard, RMS leaks in general are a function of a crankshaft end journal that is not quite round - a small manufacturing defect.

The seal holds the oil until there is too much play (compressed seal) and then begins to leak. I expect yours sits, with the crank in one position, hardens into that position, and generates a leak.

The question really is: 1) how much oil and 2) does it continue or subside once its back in use? If its a minor amount of oil or it subsides - don't worry about it. The RMS leak is not damaging anything - its only messy. The one exception is if its leaking a LOT of oil, and then it could contaminate the flywheel's rubber core. But that's a lot of oil.

Are you using the latest, silicone seal, and is it being installed with the go/no go tool?

Grant

Grant

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

Hello Grant

Every time after parking the car I notice a couple of small drops of oil in the vicinity directly below where the engine bolts to the transmission.
For the past 3 years I have had the leak fixed in the spring, I drive it all summer and it does not leak a drop. I usually store the car after the 1st snowfall or if it gets very cold. I start the engine in the spring and I see a small oil puddle about half the size of the palm of my hand. I drive the car for a couple of weeks hoping the leak will take up but I notice the 2 oil droplets after the vehicle is parked ( this is unacceptable because any type of leak drives me crazy) . Then it goes back to the shop to have the RMS replaced.

I am not sure what tool the shop is using to replace the seal. I can only assume they are using the proper tools and procedures as they specialize in Porsche maintenance and repair.

Thank you for your reply

imtonyd

Quote
imtonyd
As I live in Southern Ontario Canada I store my 07 Boxster during the winter months. For the past 3 years, immediately after the initial engine start in the spring, oil leaks from the Rear Main engine seal. This is an expensive repair that I do not wish to have done every year. I believe that because the engine is not being run for 3-4 months the RMS is dry and without lubrication. Thus at startup the torque from the crankshaft tears the seal. The engine oil is changed before storage and I was wondering if there is an additive could be added to the oil that would prevent this RMS from drying up.

My service shop has suggested starting the engine regularly while it is storage.

Looking for a solution.

Thank you in advance for any suggestions

Lack of use can have the seal shrink. But this takes longer than a few months However, the effect is accumulative.

Believe it or not the oil already has additives in it to prevent seal shrinkage. The problem is during storage the engine is not run and the seals do not get washed with oil.

The shop's advice to run the engine once in a while is good advice. Start the engine and let it idle a while then raise RPMs to 1500 and hold for a bit then let the engine speed return to idle. You want to ensure engine oil gets slung about and washes every interior surface wtih fresh oil to ensure all seals and what have you are bathed with oil. The fuel system gets used too of course and fuel gets stirred in the tank by the fuel pump (this stiring is a by product of the design of the pump/housing which has part of the pump's output directed to causes fuel to flow over/around the fuel pump for cooling; a side effect is this immediately addresses any stratifcation the fuel might have developed from sitting.) The stale fuel in the fuel lines and injectors get flushed out and this helps keep the fuel system working right.

Ideally you'd like to let the engine idle long enough for the T-Stat to open so coolant circulates. This helps prolong the life of the hoses and other components in the cooling system.

While the engine is idling turn on the A/C and let the compressor run. This circulates refrigerant and compressor oil through the system and helps keep the A/C seals/o-rings pressure and fluid tight.

With fresh oil the engine starts out with no water in the oil. The bit of running may introduce some water into the oil but it will be minimal. And if you let the engine idle long enough that the oil gets "hot" because the crankcase ventilatiom system will have the crankcase at less than atmospheric pressure the boiling point of water (and any unburned fuel in the oil) will likely boil and be removed so there will be minimal build up of these contaminants over the winter season.

Come the return of the driving season a nice long drive that has the engine up to temperature -- the radiator fans running on their own is a good sign the engine is "hot" -- will have the water and unburned gasoline removed. Then come the start of winter you change the oil and repeat the process.

Regarding the actual oil leak Pedro asks the right question. A few drops then no more is not a real problem. 'course, if everytime you park the car a few drops appear under the car then that's a "problem".

When the RMS is replaced the new one must be handled with care. It must be installed squarely and surely the shop knows this. What it might not know is the new seal should *not* be installed at the same postion as the old one. The old one can have worn a shallow depression/groove around the crank journal and if the new seal is installed in the same place because of this shallow depression/groove the new seal doesn't well seal as well and leakage can occur.

The seal should not leak with 0w-40 oil. When my Boxster's RMS was replaced at 25K miles -- under warranty -- the engine had 0w-40 oil. After the seal was replaced there was no leakage. And the seal has remained oil tight for over 290K miles most of these miles covered with 0w-40 oil in the engine. Only in the last year or two did I switch to 5w-50 oil but not out of any concern for oil seals simply because of the very high ambient temperatures here in the summer coupled with the very mild winter temperatures that don't even get close to the point 0w-40 oil should be used.

Bottom line is if the RMS leaks frequently and you want this addressed a new seal is required. But it is important that as I covered above the new seal be replaced correctly and the new seal's installed depth be considered to avoid installing the new seal at the same spot as one of the previous seals.

After the new RMS is installed consider running the engine regularly during the winter to help the RMS and other seals/gaskets/etc better avoid the effects of lack of regular use during the winter.

I also live in Southern Ontario and have owned my 986 for 16 years.I store it every Winter generally December - March. Connected to a battery maintainer, lots of air in the tires with fresh oil and a full tank of gas, the car sits untouched until Spring. It starts first time always. No leaks of any fluids or oil ever. It's a dry as a bone and runs better than new.

Hello MarcW

The engine leaks a couple of drops every time it is parked which I cannot live with.

Running the engine periodically seems to be the most practical solution at this time, even though it seems to be a split decision according to other Porsche forums which recommend that the engine not be run unless it is to be driven. But I know this option does not work in my case

Good idea re running the A/C periodically as well.

I believe the RMS is being replaced properly as the shop specializes in Porsche maintenance and repairs.

I will try using the 0w-40 oil but I am skeptical that it would make a difference. I know it can't harm anything.


Thanks for the tips and info