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100K miles. Is yours above or below?

If you follow regular maintenance and checks, the 'pre-emptive' work can be done when signs of failure are imminent.

If you are unlucky, sudden failures can occur but that is true in life of many things and most of us have researched the risks of ownership before hand.

Hartech are clearly experts and excellent at what they do.

There is no one-size fits all answer to this debate as age/mileage/condition is all relative to cost of vehicle.

All the above debate is interesting never the less.. :thumbs:
 
Wasz and Marky,

I'm not challengng your views or opinions, but for accuracy, where do you get your £10k figure from? Baz's guidance price for a crank repair is around £4k.

If it is really a £10k rebuild that is needed, (new bore liners etc) the engine will be on its last legs and this cost unavoidable.
 
No problem bluebird, it's all just opinion. :thumb:

Baz said
"So a pre-emptive rebuild with the new parts fitted for around £7.500 + Vat that eliminates or protects the weak areas can make some comparative sense for those intending to keep and enjoy the car"

You can gonin and do less but if you're going in that far it would be a slightly schizophrenic approach to maintenance to say "Ok I'll rip my fully working engine to bits but I'm not going to strengthen the cylinders etc, I'll do the bare minimum".

Again it's all just our own take on things and how we perceive risk.
 
Thanks for this Marky, I understand now! :thumb:

I was specifically looking at the crank repair:

Baz's guidance: 'We can do the whole job (Non Maintenance Plan) of replacing the crankshaft shells (which is the main issue we have raised with over 100K cars) for £3630 + vat'.

Cheers
 
No problem Blue,
yes I saw the various figures and that crankshaft one isn't bad when viewed in isolation, however having had several 911 engines rebuilt over the years you never open one up and find it only needs the minimum you'd hoped for. :grin:

It's always a case of "while you're in there you'd be daft not to do this and that". That's why if the car was going to Hartech I'd want the full works, otherwise if you came to sell it you'd only have prospective buyers saying "Well it hasn't had a proper Hartech rebuild has it". :wink:

My main reason for posting on this thread is if there's enough noise made about the engines needing a rebuild by 100k even if its still running fine, then people may start to believe it.
This opens up a whole can of worms when in he future you start to get buyers who aren't fully clued up saying "Well Baz from Hartech says they should all be rebuilt by 100k miles".

To me personally if a car is running fine, making good power, not drinking oil or making any noises then just enjoy it. Trying to second guess and head off problems that may not even be there is just madness and if I was that scared of the future I'd never leave the house, let alone drive fast cars. :wink:
 
Yes, I do agree with you Marky that if the engine is opened, do all that is necessary.
:thumb:

I really don't want to extend this thread any further, but I don't thnk that Baz is saying "Well Baz from Hartech says they should all be rebuilt by 100k miles". He has gone to great length technically in his first post to explain the relative thinness of the bearing shells (in common with modern manufacture) and the crankshaft characteristics that shell wear is a potential problem at 100k. I think he is leaving the choice of rebuild open to the owner, but simply making us aware of his experience.

I have been looking for my next car and a Ferrari or V10 BMW needs this work much earlier (about 50k) so, you wouldn't dream of buying one of these without factoring in rebuild costs.

I have said in earlier posts that I would not buy a car at 100K for these sort of reasons, but to others there are some bargains to be had. At 90K I should have sold my car a couple of years ago, but I'm enjoying it and that is what ownership should really be.
:D
 
There are definitely benefits to rebuilding before it goes pop but owners will individually make that call and there will be many factors dictating how one may proceed.

My C4S crank bearings were thread bare at 115k so glad I took the advise of the specialists to have a look in the bottom end while doing the required top end rebuild that took the car off the road. This did show of course that other areas required attention notably oval cylinder bores and who wouldn't put a new set of timing chains and guides in, check the ims bearing etc at the same time??

Prices are rising and there seem to be more and more threads of potential owners desperately trying to find nice clean cars. The c4s as an example is now into the 20k price bracket so perhaps owners would think hard about a rebuild as opposed to scrapping the vehicle for 6-8k (as there's no cheap buy in option now) if the engine let go and this will filter to the other base model cars in time just as it has with all 911's.

Do what you can to prolong engine life as all the m96 issues are known and enjoy the ride :thumb:
 
Exactly, one way or another a performance car is going to cost you, it just depends which way around you want to do it. :thumb:

My car is on 75k but the engine is only on 65k due to an IMS failure, so I'm not even too interested in the 100k mile debate. I just think there's already that psychological 100k barrier there and talk of needing, or at least recommending needing a rebuild by this milestone too, only causes more concern amongst owners and buyers, but yes as you say, the info is there for us all to interpret how we see fit.

:thumb:

Right I'm not looking at this thread again now. must resist. :grin:

ETA - Yep Harv, you approached it properly and done a proper job! 8)
 
I had to get mine rebuilt, engine sounded sweet with no rattles at all, my symptoms were low oil pressure at hot idle to the point the oil light was on.

I changed the oil and oil pressure sender hoping for the best but the tell tale was the glitter ball in the bottom of the oil filter housing and the debris in the oil filter.

Upon restarting the car again everything sounded perfect so I found it hard to believe the bottom end was dying, same problem at hot idle oil light on, I drove for about 250 miles and opened up the oil filter again to reveal the same.

At this point there was still no rattles from the engine ( I've had big ends go before so know the noise) car still sounded spot on.

In the end it went to Hartech for a rebuild, when speaking to Grant he said that the crank wasn't serviceable so he had to source another crank, must have been run to long with the existing bearings and caused damage to the crank journals. I was hoping that existing crank would have been fine due to the fact it wasn't knocking but I was wrong, when they go tits up there proper expensive. Anyway just my 996 story
 
As I've mentioned previously, I've been putting some cash aside every month as as a contingency for 'engine work' since acquiring my 996 two and a half years ago.
Having absorbed so much great information from this site, not just from the likes of Baz/Grant Hartech and the other specialist companies with vast experience of this marque but also from the people that own, drive and fettle them and who have all contributed freely, I feel that I was making a well informed decision at the point of purchase. Well as much as you could expect from a thorough inspection and test drive of the car, studying a folder full of bills for maintenance and servicing and an hour interrogating the 8th owner.

The mileage query thread I originally posted was to gain some insight into the numbers of cars being used with over 100k miles on them but I don't think I was really asking the right question!

The pre-emptive rebuild is something I will be considering and will speak to Hartech about potentially joining their maintenance plan as technically I'm already saving the money each month to cover those costs, subject to a proper inspection which I can coincide with the next big survice due next Spring, and understanding the extent of any exclusions.

Some folk will think I'm mad others may agree it's the sensible thing to do despite the seemingly high costs. My car still feels pretty good despite the 91k miles travelled by the previous 8 owners and the 9k I've done in it, but I love driving it and intend to keep it and therefore feel the engine work will be money well spent in the long run, especially if it can be managed via modest monthly contributions.
I'll probably document the whole thing on here for information and thereby give something back to the forum. It's up to everyone what they take from it. :thumb:
 
Readers may remember me pointing out that we were getting an increasing number of engines in for rebuild with crankshaft failure and my advice to consider a pre-emptive rebuild on higher mileage M96/7 cars on the grounds that by 80-100K many have oval cylinders, worn piston coatings and worn crankshaft bearings (and that we are placing some restrictions on suitability for joining our Maintenance Plan for higher mileage cars).

Whereas repairing the cylinder side can usually be left until they need doing - a crankshaft failure always kills the engine and is going to add several thousands to the rebuild cost that could have been avoided.

So following criticism of my advice then and claims of scare mongering - I thought you may be interested to know that we currently have 6 engines here for rebuild requiring crankshafts - several of which we will have to buy new as good used ones are like hens teeth now.

Crankshaft flexure (because of the large overhang at the flywheel end and the relatively thin rear main bearing) seems the most common cause in engines failing sub 100K whereas those who restrain from engine braking tend to last longer (although previous driving styles are usually impossible to evaluate in multiple owner cars).

Racing engines suffer the most because of the rapid change down and engine braking that becomes part of the punishment the cars experience (often under 1000K).

Good quality oil of the right viscosity can also help delay wear but eventually only the most mechanically sympathetic drivers will get long life from the crankshafts.

To help in racing to start with - we are testing a solution to minimise crankshaft flexure during clutch engagement (changing down) and if successful this will become another option for future rebuilds.

For most applications owners wanting to keep their cars for many years ahead who have engines that have covered over 80K - the recent increase in crankshaft failures (that we had already noticed and advised about) does seem to substantiate our previous advice to consider pre-emptive rebuilds.

Baz
 
What variants are the 6 engines Baz? 3.4/3.6/3.8 M96/97?
 

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