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chicb said:Pazuzu, after all these posts of, is it/isn't it borescored, the chances of a quick sale I would suspect is fairly low. Throwing in my 2 pence worth, I would take it to Hartech for a borescore check & get their results in writing with the photographs. If it turns out fine, you basically have an unofficial guarantee from a well respected engine builder to show anyone looking at the car with no ifs, buts, maybes. Should the results show it is scored at least you can then decide what you want to do.
Its amazing how perhaps a good cars condition can be shredded by a few keyboard taps. A little knowledge is a dangerous thing comes to mind. Best luck anyway.
bazhart said:Impressed with the knowledge many of you have picked up over the recent years.
Pictures are indeed hard to interpret but none of them look like scoring to me.
Although our web site contains a lot of historical information about t he subject it is several years out of date and so I have recently written updates on the bore scoring issue that will soon replace the old text and will answer all of the questions raised.
There is too much involved to reproduce here but just to correct one thing - there are 4 repair modes, new crankcases with the same potential failure Lokasil bores, iron liners (of which we have many that subsequently failed and the new report explains why), plating onto the scored cylinder and replacement with alloy Nikasil liners (of which there are 2 versions on the market and ours is different than the other because it also d=secures the liner at the top and results in it becoming a closed deck method which is generally recognised as superior). Several thousand have been replaced and over a thousand engines rebuilt by us this way without issue.
However when a customer order is accepted for a bore score we cannot insist on all 6 being replaced although (as this post demonstrates) for those unable or unwilling to pay for all 6 use our less expensive alternative - it still has worked well for tens of thousands of miles.
It is always easy for miss-information to discredit or harm suppliers unfairly and as in this case I do wish those responsible would have the courtesy to contact us to find out the full story before deciding to post their opinions.
I hope the new report on bore scoring will help clear u p a lot of the always present confusion - due in probably 3 - 4 weeks time.
Baz
bazhart said:Not Quite "no one knows?" I have stated my opinion - thank you!
The nearest I can get to an analogy is a windscreen with marks where the rubber blades have put minutely small dulling to the otherwise shiny surface that can be seen sometimes like a smear over the surface.
If you measure an original Lokasil bore after say 80K you may find it is around 6 or 8 thou oval and if you measure it at 10 degree intervals round the bore there will be lots of peaks and troughs but because the bore is more dull it is not obvious to the naked eye or a boroscope.
Similarly iron liners will have little ovality but be worn in patches slightly but not show.
Nikasil in contrast is harder and will retain a superb roundness for years. On the odd occasion when a racing version has blown a big end or dropped a valve - we have almost always been able to recover the engine with the original Nikasil cylinders - the surface is that good.
However it is difficult to match ring material to it. The 911 SC 3 litre and 3.2 Carrera models had Nikasil bores and less "polish marks" but the rings were worn down to a point at the ends after around 70K while the compression dropped at low revs making the engines . run at low power until the camshafts kicked in with better timing where they designed the power band.
The M96/7 engines have rings that will last for at least double that mileage but will polish mark cylinders with absolutely no detriment to the running of the car.
It is really unfortunate that the public - aware of the problems - and rightly wanting boroscope reports on their cars (or before buying) and mechanics and engineers do not understand the differences between polish marks and scoring (not really their fault though).
Nikasil is applied a few thousandths of an inch thick and if it ever scored there would be deep obvious grooves in the surface. Lokasil scored would bee even deeper grooves and usually o ver a wider width.
The reports from the owner demonstrate that the engine was working perfectly - low oil consumption and good power after many years and tens of thousands of miles and could have been presented as confirmation of the good work we do for our customers rather than initially appearing to do the opposite. It could have said "this engine has done 30K and lasted 5 years after a partial Hartech spec rebuild (due to the warranty company) and is still going strong" instead of casting doubt on the well proven and supported solution.
That is why I appeal for anyone suspecting . problems with our products or workmanship to please at least contact us before making up their own minds first, posting on that basis and finding out a more accurate understanding afterwards.
The Internet can be a tough place anyway at the best of times and I feel the good work we do for our customers deserves a little more respect than we sometimes read about.
Baz
Alex said:Narrow escape - bore scored Hartech rebuilt 'S' engine
:?:
infrasilver said:Alex said:Narrow escape - bore scored Hartech rebuilt 'S' engine
:?:
Fairly damning
Hertsdriver said:infrasilver said:Alex said:Narrow escape - bore scored Hartech rebuilt 'S' engine
:?:
Fairly damning
Or completely factual.
But regardless there is no insinuation of any wrong doing on the part of Hartech in that sentence that I can see?