Need help on an Oil leak in right rear of engine

[Steelepuls]

New to the forum, love it for the very informative tips and DIY. Recently purchased an 01 Boxster S, with a weird oil leak. It's coming from the right rear side of the engine between the block and the tranny. It's at the 2 or 3 o'clock position tranny bolt. The oil seems to be coming from the crevice above the bolt. Oil drips on the floor, about 2-3 inch puddle after I drive it. The bolt head behind the wire is where it's visibly dripping down onto the side of the tranny. Sorry for the bad picture, best I can do on my back with very little room for the camera. Could someone tell me where the oil is coming from. It only leaks when the engine is running and at temp.
I've replaced the air oil separator, and oil filler tube based on the initial assessment. All of these parts are dry and oil free now and I can easily take off the oil cap.

[Gilles]

Hello Steelepuls,

Perhaps be a good idea for you to clean the engine (engine degreaser or Simply Green) then flush with 'low pressure water' this way it would be easier to determine the source.

Since you already replaced the AOS (and) assuming that all the hoses are tight, you may have a leak on the valve cover or one of the sensors that attach to the engine, but with a clean engine it will be easier to isolate.

Good luck!

[husker boxster]

I was going to suggest it could be the AOS. There is a rubber seal around the bottom that was leaking on my LE.

Since you've replaced it, I agree with Gilles to clean your engine and see if it's still leaking. Put the top in service mode, pull the engine cover, and clean from the top of the engine as well as the bottom. Do not use high pressure as you can cause numerous bad issues if you do. Get a can of Gunk Engine Cleaner, spray it over the AOS base area and lightly wash off.

This will be a good starting point. If it works, easy fix. If not, you've checked off a couple of boxes - changed AOS and cleaned area.

[Gilles]

A cleaning tip (that I used a couple of times) and worked great...

stop at Home Depot and but a roll of the thin plastic film used to protect the carpets when painting a wall and unfold it underneath the engine and transmission (between the rear tires)

This way when you apply the engine degreaser (Gunk or Simply Green), all the crude will be falling on the plastic, afterwards you fold the plastic with the mess inside (to the trash can) and get the floor of the garage wet before rinsing the engine and gearbox this way the oily residues will not stick to the floor.

Remember to use the water hose with 'very little pressure' so you don't risk getting water on any of the electric connectors.

Good luck!

[Steelepuls]

Thanks all for the response and the recommendations.

I managed to clean the area and took the car around the block again. When I got it home this I what I found. Oil is coming out of the crevice above the tranny bolt and dripping down the side of the tranny. Is this the dreaded RMS or IMS seal?

[Timco]

Could be trans oil coming from main seal on shaft from bell housing to gear box. Can also be RMS. I'll say RMS.

Antioch native here...

[kevinle92618]

I just went through the similar leak (same spot) with my 01 non-S tiptronic trans. I also poured dye into the engine oil but the result was inconclusive. You can read my post here

Which one, engine or transmission, is leaking oil?

Finally, this past weekend, I just replaced the engine oil & filter. Immediately, I can tell the leak is not from the transmission because the leaking fluid is clear & clean (like the oil I just poured in). This plus a few people from the forum believe it's likely an RMS leak made me feel more confident.

Since my car is 16 years old, and it costs an arm and a leg to fix this leak, I think I'll just put a pan underneath the car and watch the oil level. Hope this helps.

[Steelepuls]

Kevin, I can confirm the leak was coming from the RMS. The RMS disintegrated from what the indie told me. The oil was only leaking when the car was running, after it had warmed up, the oil would get spun out of the bell housing through two openings at the 2 o'clock position. I am happy to say, I had it replaced last month along with the clutch and pressure plate and I've been daily driving it ever since. No more oil on my driveway and garage :dance:. Trying to get as much driving in before the winter comes. Love driving my Boxster. Need to get some new rear tires and get an alignment next. Good luck with your Boxster.

[husker boxster]

Thanks for the follow-up.

Originally Posted by Steelepuls

Trying to get as much driving in before the winter comes.

Winter? You mean like this?

[Steelepuls]

Lol, no more like this. We don't get the solid stuff here. Just the wet stuff.