Excessive oil consumption

[JustJames]

I know there's two plugs to come off. I assume they're farely obvious? Do you think I'll need to replace the washers. Last oil change was in November. If so, where do I get them from?

 

Are the filters pretty standard and available from somewhere like autobarn? Can anyone tell me what type I need or where I can find out? It would be handy to have the replacement before I start.

 

I've got one of those vacuum contraptions  that sucks the oil from out of the filler. I was thinking of giving that a go ... Would I be able to get enough out to avoid having to drain it out the bottom?

 

I don't have a torque wrench to do the plugs back up. Will I be ok as long as I'm not too heavy handed?

 

I've read it's possible to do it without jacking up the car. A standard bucket isn't going to fit under there so what do you guys use?

 

Anything else I should be wary of?

 

Hi Simon

 

The two plugs will be on the bottom of the engine and on the oil reservoir tank.

 

Best practice is to replace the sealing washers.  I've taken to sending washers out with oil filters.  Other suppliers of parts should be able to supply the washers.

 

The filter I sell for 911 models from '74 to '94 is a Mahle OC54.

 

Oil vacuum pumps are designed for wet sump engines, so I don't think it will be very useful for a 911.

 

If you have a reputation for excessive strength and stripping threads, you should use a torque wrench.  

 

My approach to avoiding stripping threads ever since I fubar'd a 50cc motorbike head by overtightening a spark plug when I was a young 'un (Hi Dad!) is to hold the wrench at the head, so that I don't have leverage and just nip filler plugs up.

 

Disclosure - I've never done this job on a 911 so if anything I've written is way off base, feel free to correct me.

 

James

[Doish13]

As a side note I've recently noticed how many older Porgas are parked at home with a mat under its engine to catch the drips. These have ranged from cardboard sheets to shag pile carpet.

Almost a subject for a new thread - what do you have under your P?

Mine drips an annoying one drip.... if that a day when parked hot and then nothing..... currently planing to place an old Persian rug under it.

[Simonk]

Hi guys

 

Thanks to those who have responded since my last post.

 

I thought I'd add some findings for those who might use this thread as a resourse in the future.

 

I drove the car up to Shepparton during the week, a round trip of 450kms. I continued to monitor the oil usage throughout the trip. My point of reference on the dipstick to work out when I'd used a full litre of oil was half way between min and the end of the stick. I know, not ideal but I know there's still a tone of oil in there at this point. I left Melbourne with the dipstick reading a touch above min. First check was at Nagambie which I think was about 130kms and included peek hour in Melbourne. Dip stick read about 2mm below min so it had used quite a bit of oil at this point. I then checked approximately every 100kms or whenever I could find a flat rest area. Each reading barely dropped from the previous reading. By the time I got back home (and endured another peak hour all the way from Cambellfield to Bentleigh) the oil had reached my reference point and I'd clocked up a total of 800km for that litre of oil.

 

So the type of driving has a dramatic effect on oil consumption. The first 350kms of the test were mainly city and peek hour kms and the car chewed through the oil. The last 450kms were mainly on the Hume Fwy where oil consumption was much less. It makes sense because the car is never under power or deceleration. Porsche apparently say that 1,000kms per litre is within spec so I'm not that far off and if changing to a thicker mineral oil helps, then I'm almost there. I'll update the thread when I eventually change the oil. I need to stop driving it to work too, It's supposed to be a weekender!

[Simonk]

Hey guys

Thought Id update this thread. Since my last post I've put Castrol Edge 25w-50 in the car and dumped the Mobil 1. I've now clocked up 1,100kms and used 1 litre of oil. That's 1,100kms on the Castrol compared to 800kms on the Mobil 1. The results back up what was said earlier in the thread.

[Vas]

That's better Simon.

+1 on the Castrol Edge, that's what I run in the 930. 

[wasserkuhl]

Good stuff.

 

Try Valvoline Hi-Vis 20W 60 Next time, it will reduce even more.