SanDiego928

Just had the oil changed at major chain shop and supplied a new washer. No leak at drain plug before oil change. Now, leaking enough to make a small puddle in an hour. I already had them put the old washer back in - better, but still leaking. It is not a crush washer like I have seen for motorcycles that actually get crushed. The Porsche one is only an aluminum washer. I have 2 of them.

Going back tomorrow - remove oil (clean container) and see if I can get the leak stopped with their time and tools or they will give me half the cost back. So any suggestions that could help is appreciated.

Questions are;

Use a different material - copper, nylon?

Heat up the washer (make it softer)?

Torque it down more?

Any tricks of the trade for this one?

Thanks loads........

Maleficio

Cross-threaded?

heinrich

I was thinking cross-threaded. PM sent.

Leon Speed

I don't know about '81s but on later models the crush washer is copper.

oaros

Aluminium on my 1991, 900.123.118.30

SanDiego928

Should not be cross threaded, but this is the first oil change in my possession so I can't say for sure and I did not remove the plug myself or check the threads. So, I'll find that out soon enough this afternoon and I am looking to see if there is a good alternate for the Porsche washer since it is seeping from that location and it is not working.

Landseer

The aluminum washers get pretty well scored and deformed.

Try flattening if needed, then dress it lightly with 600 paper.

Might need to dress the edge of the pan contact surface as well.



Am not a fan of re-using oil under any circumstance. It comes out, its discarded. Too much chance of picking up grit.

SanDiego928

I used a new washer and it leaked worse than the old one. I will lightly dress the edges today and report back. I hate these little items that slow me down from getting to the bigger sorting out things.

I hate reusing the oil but 80 bucks is 80 bucks. I hope I can minimize grit to zero.

Thanks.

davek9

If you back out the Drain plug a bit and clean it off best you can, put a smear of silicone sealant in the threads and re tighten. This may stop the leak until you can do a proper clean up as suggested and install a new washer. This has worked for me, I hear you about re-using the oil

Dave

Stromius

You may be able with an assistant (with a large thumb) to remove the plug with minimal spillage and put a new cruch ring on. YMMV

Tim968

I like Loctite 515 on pan-side of the washer, and spec torque (30 ft-lb). If the plug doesn't run easily with finger pressure I'd be sweating a cross-threading event. I've used the Loctite 515 on lots of aluminum plugs, German, Britbike, very successful, easily removed with a scratch awl on next service. I've never studied the idea of a thread-insert repair on a 928 pan...

Mrmerlin

before you go to more oil draining scenarios try this ..
get a tube of loctite PTFE pipe sealant,
it comes in a white tube,
get a can of brake cleaner,
then put a drip pan under the plug,
back the plug out about 5 turns,
rinse it off with the brake cleaner,
then put some of the sealant onto the plug threads then screw it back in.
this should seal up your leaking threads ,
my guess is that the oil pan has been fixed with an insert ,
and the insert threads are passing the oil .
If this method doesnt work then,


remove the plug and drain the pan.
clean the threads out with the brake cleaner,
smear a small amount into the oil pan threads,
fit a new sealing washer,
add some of the sealant to the plug,
insert it,
then let it sit for an hour so the sealant can set up,
then refill the oil

SanDiego928

Washer was not centered perfectly to match abraded surface of pan. Years of friction, duh - 30 years, caused pits and gouges around pan threaded hole. The washer not being centered in worn area exactly; caused severe seaping. Used some teflon tape with new washer to keep it centered on plug. Looking good so far after 2 hours. Still needs future attention though.

Many thanks to all for helping me to continue forward in my 928 endeavor.

I liked all the responses. I feel better. I could not find “using search” this exact topic.

Liked the Loctite idea and sealant - next years choice? That would have worked perfectly in this situation and I just read the backing out response from Mrmerlin. Nice combination of choices. I have learned plenty.

Mark

SanDiego928

Oh yeah, very scored. Worn thin on edges.

Maleficio

I installed a Fumoto drain valve on mine. Sealed perfectly with provided washer, and no tools required to drain the oil, thus less wear and tear on the plug and hole. $30.