Ben, you're thread's got me worried. My 993 C4 (1997) has 83,000 miles on it - I bought it in May and have put 4,000 miles (mostly motorway driving) on it.

The engine feels reasonably strong (although I haven't compared it to any other 993) and I seen no reason to take it apart, etc.

I was told by a very reputable specialist here in the UK (JZ Machtech) that the engine shouldn't need a top end rebuild until about 120-130,000 miles.

Although this is comforting in one sense, it is also frustrating: I want to rebuild the engine, instal a performance chip and a LWF, etc.

The car is just too reliable at the moment!

Does 120-130K without a top end rebuild sound reasonable? Bear i mind that I live in the UK so that the car hasn't experienced great extremes of temperature (although it has, no doubt, spent much of its life sitting in awful traffic).

Any views welcome (particularly those that suggest a rebuild is imminent...)

 

Your best bet to determine need would be oil consumption. Search and you will see that consumption varies widely. Generally if consumption is > 1 qt. per 800 miles or so, may be at least time to start thinking about some work and close monitoring of consumption. Also, many on this board have had their motors last well into the 100k range without any need of top end work. Take off the undertray and watch your oil consumption.

 

I wouldn't worry - if you are concerned do a compression/leak down test. If all cylinders are in balance and in spec (~180 psi), and you are not using excessive oil you are probably fine.

Mine showed low compression on two cylinders - and one of those had a bent exhaust valve. Much of the other damage was oil or heat damage (wiring harness, spark plug wires, etc.).

As I see it my situation is just a combination of:

1) Heavy use
2) Moderately high mileage
3) Hot climate
4) wrong end of the bell curve

Ben

 

You know Ben, one of the things that I wanted to point out to the group is that I think your engine wear is unusual. I was waiting for people to start thinking that their engines needed a rebuild after 75K miles.

I know I've had my top end done at 45K miles but it showed no wear. It was done to try to solve the check engine light issue but we all know that doesn't solve it. Anyway, the top end had nothing out of the ordinary but they did replace the valve guides.

My motor lives in the same environment as yours and has probably two to three times the track miles of yours. It shows no sign of power loss thus far and I'm about to hit 75K miles.

George

 

Ben,

What kind of oil have you used over the past 75k and how often was it changed?

 

Mobil 1 15-50, changed every 3000 miles.

But I've only owned the car since 35k miles.

 

I would have expected better results from the oil and your maintenance habits. Who knows what took place in the first 35k though.

OT any idea where I could get those special lowering Bilstein HD's stateside?

 

Devek had them at one point - got mine from Gert.