bojali

orignal owner, 180k no top end, 2nd clutch, passed CA smog quite well, Mobil1 5-30 on factory recommended service schedule. Mine is a daily driver

I would assume that these that have high mileage are due to owners with regular maintenance schedules?

Falcondrivr

I use mine as a daily driver and then on track for 5-6 weekends a year. Subsequently, it gets an oil change once a quarter, and constantly upgrading and replacing wear parts.

SleepRM3

Deleted

pp000830

My car has 90k on it and had the valve guides replaced early in is life by a previous owner as an oil consumption issue under warranty. At the time the car was located in New Mexico where the hot climate, some feel, accelerate valve guide wear. The engine now uses no oil until the oil has about 5K to 6K miles on it then it uses just a very little. This is about my total yearly miles driven interval where I change the oil. Suggests that the oil at 5K miles is just beginning to lose its ability to hold viscosity and is slipping past the rings a little more. I see a little oil wetness around one of the oil return tubes under the car but no smells or dripping in the floor when parked. During oil changes I change both filters and drain at the engine case plug and the reservoir. I do not unbolt the tube specified in the factory method. To get to the smaller filter i just remove the rubber duct to the heater flapper assembly on the passenger side and when done hose off the bottom of the engine with CRC electrical contact cleaner as removing the smaller filter seems to be rather messy for me.

Martin S.

Leakdown: Wish the #'s were like Ilko's, but it is what it is:
1: 6%
2. 2%
3. 4%
4. 5%
5. 4%
6. 3%

No significant oil consumption. Car puts out 255 to the rear wheels. May do a prophylactic rebuild at 100,000.

ilko

Heh, old thread but I have a "new" car so might as well go again.

My current 993 has I think 112K miles on it now. Oil consumption is non-existent it seems, on Brad Penn 20W-50. I put 3K miles on it this year and didn't have to add any oil... Never bothered with a leak down test but the car pulls really hard and the motor is strong. I drive it like I stole it every time, no babying! No CEL due to clogged SAI or any other fault codes.

My previous C4S I sold with about 110K or so. Local guy purchased it as a daily driver in March 2013 and put a decent amount of miles on it. We still keep in touch and I haven't heard anything about a top end.

BTW, the VINs of my current and previous 993 are just a few digits apart. The cars were built within a couple of weeks of one another at the tail end of 1995. They must've built a strong batch of engines at that time

ble2011

Mines close to 90k. No signs of excessive oil consumption and runs great. No top end rebuild or valve guide replacement. I'm going to continue driving it until I notice an issue.

911F1

109k miles. Running like a champ. Very impressed on how well it runs at this mileage. Can't say the same for previous high mileage cars I've had in the past. Ex: Audi, VW.

Pags993

At 109,738 miles now and still zero oil consumption running 20W50 V Twin formulation. Car still pulls like a freight train and runs like a top, hopefully for a long time to come!

bojali

now 195k miles .. same

eddie_993

Mine also had 180k miles with no top end rebuild...smog is a different story though

Knight

Some impressive #'s on this thread!

earossi

I hate to mess up the love-in that is going on with all these high mileage cars; but, one has got to wonder why many of our cars will never hit 100k miles without needing valve guides, while other cars can go two or three times as long on the original heads?

For comparison, let's look at my car. It has had 4 owners. It had 103k miles on the clock when I purchased it. During the PPI, leak downs on all cylinders were in the 5-6% range which is not unheard of for high mileage cars. The important thing to me at the time was that the leak downs, though a little high, were pretty much equal cylinder to cylinder (telling me that nothing was broken in any one of the cylinders) and not unheard of for a high mileage car.

The car had complete records and appeared to have been well maintained. Since there were no CEL, I assumed that things were OK. So, I continued to drive the car hard, which is how I drive all my Porsches. Car ran well and strong. The car used no oil in the 4k miles I put on it initially.

Then, I got my notice to have the car smogged (every two years in Illinois). The car flunked for SAI codes and bad CEL. Checking for a burned out bulb, I was unhappy to find that a PO had removed the bulb! After replacing it, it did not take long before I got the dreaded CEL for SAI. And, the car flunked the emissions test.

So, with high leak downs, several nagging oil leaks, and plugged SAI ports, I decided to do an upper end rebuild on the car. I had done several other 911 engines over the years, and felt that it would be a fun experience for me (poor wisdom!). Past 911's I had done power train work on usually required 4-5 hours for me to remove the power train from the car. The 993 took 16 hours, even though I now own a lift! And, stripping down the motor took much longer as well.

After a disassembly of the top end, I sent the heads to Steve Weiner for a rebuild. His comment back to me was that he had not seen heads as bad as mine very often. The exhaust valve guides were extremely badly worn. And, this at 107k miles.

So, I began to wonder about oil and oil changes. So, let me comment that both the connecting rod bearings (big and small end) and the crank bearings, looked absolutely perfect.......no signs of wear or dirty oil. The intermediate shaft bearings did show wear, which is not uncommon. The car's records showed religious oil change intervals.

So, why did my engine's heads turn to toast in 100k miles, while other owners are able to get twice or three times the run cycle out of their heads? That is the question!

goofballdeluxe

I'm sure you are aware that CEL for clogged SAI ports and the need for a top-end rebuild can be completely unrelated issues, right?

In your case, it sounds like you also needed a rebuild, but often a CEL due to SAI can be fixed by a simple clearing out of the SAI ports, which is mostly labor intensive. A mechanic will probably charge around $500-$800 for the pleasure of clearing them for you. Sure is cheaper than a new top-end, and, for most, will either negate your expensive experience, or at least, prolong it significantly should the car not be consuming too much oil and the leakdown/compression numbers come back within reason

race911

Selective editing here, so I'll respond to each paragraph I've highlighted:

1. I'll mess up the love in. Simply put I've not see an OE 911 guide worth a ____ past about 80K. My decades long statement is that if they were as easy to change as brake pads guys would change them out with every other oil change--.0001 stem taper would probably have a freak out thread here that would dwarf oil discussions.

2. Sorry to hear engine extraction took so long. Absent rear suspension disassembly it all comes out pretty straightforward like all models past.

3. Always nice to hear back from the world class guys who have massive amounts of experience.

4. Your heads didn't turn to toast, the guides did. Absent smog check/CEL/resgistration problems you can pretty much drive the things forever. If you want to. (Realize in the Olden Days you'd puke a tensioner 30-60K out, and the factory valve guide replacement thing would be forced on you.)