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Cracked crancshaft on my 3.4 2001 MY

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Old 07-21-2014 | 09:54 PM
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Default Cracked crancshaft on my 3.4 2001 MY

Hello guys,

I had faced with problem on my neunelfer(911) with blinking of oil pressure after hard riding when stopping and put the car to the local dealer. The dealer has cheked the car and ensured me that no reason to panic. The engine was filled wth fresh oil Motul excess 5W40 before it started to blinking and no blinking was observed on the previous oil. The oil was bought through the local dealer. The next day was terrible as on way back to home the oil pressure at once starts to light constantly and check engine light has started to light as well. After that knocking sound appeared from the engine.
When the engine was dismantled it was discovered that cranckshaft is broken on the centre of the web. The bearing surfaces has traces of excessive temperature and scratches.
Please offer the cranshaft in good condition with single gear as I can't find something suitable, used & good through e-bay or similar sources.

Thanks in advance for your understanding and cooperation!

Photos and additional info on request.

BR,

Andrey
Old 07-21-2014 | 11:13 PM
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Flat6 innovations is who you need to get in contact with
Old 07-22-2014 | 08:51 AM
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Thank you! I've tried to contact him.
Old 07-22-2014 | 09:11 AM
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Originally Posted by Noble Fox
Hello guys,

I had faced with problem on my neunelfer(911) with blinking of oil pressure after hard riding when stopping and put the car to the local dealer. The dealer has cheked the car and ensured me that no reason to panic. The engine was filled wth fresh oil Motul excess 5W40 before it started to blinking and no blinking was observed on the previous oil. The oil was bought through the local dealer. The next day was terrible as on way back to home the oil pressure at once starts to light constantly and check engine light has started to light as well. After that knocking sound appeared from the engine.
When the engine was dismantled it was discovered that cranckshaft is broken on the centre of the web. The bearing surfaces has traces of excessive temperature and scratches.
Please offer the cranshaft in good condition with single gear as I can't find something suitable, used & good through e-bay or similar sources.

Thanks in advance for your understanding and cooperation!

Photos and additional info on request.

BR,

Andrey
Do you have a LWFW on the car?
Old 07-22-2014 | 09:36 AM
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No, I don't. It's fully stock with automatic transmission. The engine was rebuilded about 25000 km ago with installation of new liners into engine block due to scoring. What was the reason of the oil pressure light blinking after hard driving? Bad oil quality? Viscosity was not enough? If the outside temperature was higher than 20C and it was sunny the blinking process during stopping has started earlier.
Old 07-22-2014 | 09:54 AM
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Some photos to your attention, guys!
Your suggestions regarding the matter are highly appreciated!
Attached Images     
Old 07-22-2014 | 02:33 PM
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The crank may be repairable which would save some money. There are also some salvage 3.4 cranks around if not. But you need to find the cause first. I bet JR is far too busy to take yours on at this time. Who did the rebuild? Who is doing the teardown now? Dealer?
Old 07-22-2014 | 02:55 PM
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Looks and sounds like you had an oiling system failure.

You said it started after a hard run with the car? You may have broken the shaft that drives the oil pump. This is one of the weak links in these motors. But the mechanic doing the tear down should have have found this on dis-assembly? Ask if that can be verified.
Old 07-22-2014 | 05:57 PM
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Where is the crack? If the pump shaft broke, the damage woulr be far more. Those bearings haven't spun yet so that is good. If the crankshaft isn't cracked (show a picture of the crack) it might be possible to re polish.

Either way, those main bearings were starving of oil. Maybe something was blocking the oil pick up screen. The mechanic should be able to figure it out. OR the clearances were too big after the rebuild.
Old 07-22-2014 | 09:15 PM
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When you say cracked you mean snapped or the Crankshaft in the first picture is only for a 3 cylinder motor.
It could of been the movement from the broken half of the shaft that has caused the main bearings to fail, why the shaft snapped is another story.



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