Bore Scoring - Cayman S Gen 1

[Ozzie Osmond]

Pagoda1966 said:

the same problems seem to be discussed so often that you'd think every car had these issues.

I think that's the tricky thing about the whole "Porsche sportscar = chocolate engine" issue. We know it exists but have absolutely no idea

• What proportion of cars has been affected to date, or
• How likely any particular car is to suffer the bore scoring issue.

It's on the second of these points that the inputs from Hartech to this thread are interesting. My interpretation is that the most vulnerable car is likely to be a 3.4 which has been thrashed from cold or run very hot, then switched off.

As regards the proportion of cars affected I guess only Mr Porsche knows - and isn't saying. Meanwhile he's perfectly happy to collect £500 p.a. as an aftermarket warranty fee and encourage owners to keep their cars in the official dealer network.

[Phoneix]

hartech said:

We've seen bore scoring at under 15K and not seen it on over 100K (although piston coatings are getting well worn by then).

It seems dependent on several factors one of which is the piston temperature reached affecting the piston coating bonding strength, the load between the piston and cylinder bore, the ambient temperature and the rate of heat soak caused when stopping for a while after a spirited drive. Added to that we think there is a variability of the distribution and bonding strength of the silicon in the cylinder walls.

It is clear that if all the drivers from new never thrashed the car - always warmed it up before thrashing it, never exceeded UK National speed limits, didn't give the car full throttle while accelerating (especially in a tiptronic where slipping into first helps before setting off fast), whatever the quality and distribution of the silicon in their Lokasil - their engine would last longer.

But these cars should be able to be driven fast and so how it was driven and a random quality element may all make predictions very hard.

Some new owners drive very modestly and so their cars have a higher proportion that will last longer but some also can afford to treat a new expensive sports car with contempt and cause a lot of premature deterioration.

You can help by lowering the running temperature with a low temperature thermostat, third radiator (as long as it also has a control valve or thermostat), thicker oil viscosity as the mileage increases etc but there is still unfortunately a random element that can bite any owner at any time - but numbers failing are still very low and there are warranties and maintenance systems that could reduce the cost if it occurred to you.

Good luck,


Baz

Edited by hartech on Wednesday 23 September 10:17

Apologies for the late response. Thanks for this info. I guess I'll have to keep looking and try to find without bore scoring and do what you suggested.