LesField

Chaps my engine is in big trouble.

I was driving at 3mph the other day and it started making this noise:


I've taken it to an indi specialist, who thinks that the bank 2 timing chain has snapped causing a damaged head, bent valves, possible block damage etc....
Its going to be removed next week and stripped, but I've been told it's likely to cost over £7,500 ($12,000).

I'm gutted as I've recently spent £4,000 ($6,000) on it with new suspension, IMS, RMS, Clutch and a X51 exhaust.

The car has a full Porsche history and has done 80,000m and I've changed the oil every 6,000m

I thought if the timing chain had snapped it would not run. What do you think?

DBJoe996

It might run long enough to increase the multiple catastrophic internal damage of total self destruction. Engines are powerful, even if it only runs on bank 1, while destroying every engine component of bank 2. Sorry for your loss.

Flat6 Innovations

Could be a chain easily. The engine has 3 chains, one for each bank, driven from the IMS and one from the crank to the IMS.

If one of the main chains driving the cams breaks, the engine will run on 3 cylinders, as one side maintains valve timing.

I have master linked timing chains that allow for this work to be done preventatively, but also this allows a repair to be done without complete engine disassembly, which is the case with all other, noon master linked chains. You probably do have ben valves, but the pistons are probably ok. We see more and more timing chain failures today.

Don't even think about starting it up again, you are spreading collateral damage like the plague inside that engine by doing so.

Its easy to diagnose a broken chain, pull the green cam timing plugs and rotate the crankshaft pulley by hand. If the cams don't turn, the chain has failed, or the IMS has become separated.

gricec

Do you sell the master link chains? Am I right in saying you have to split the case with a normal chain?

mikeborden

I don't think you have to split the case, I've seen Jake comment that you don't, but I could be wrong.

Mike

clearwaterms

If the pistons survived but the valves are bent, Is the head usually serviceable? Is it simply replacing the valves and valve guides or do you typically have to do some machine work to salvage the cyl. head?

wilhit10

Yes..my motor bent all 12 exhaust valves. A local machine shop easily repaired it with new guides and new valves.

Chiamac

=)

LesField

Turned out my valve liner had slipped (poss overheating in the past) locked the valve, which broke the head, and damaged piston 5 and the liner. It will cost around £9,000 ($13,500) to re-build with a new head.

So I've managed to secure a low mileage 3.6 engine complete with ancillaries which has had the bores tested etc and is supplied with a warrantee which should get the old girl back on the road for a few thousand less. Also I get to keep the old engine to sell for parts. Can't wait to drive it again.
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Barn996

Too bad about your engine, but happy to hear you have a solution with a low mileage 3.6.

Imo000

Take it completly apart and sell what is good. The crankshaft, main bearing carrier and one cylinder head should be easily sellable. Heck if the intermediate shaft is still intact sell that too. Then there are all the accesories too.

Cuda911

Sorry to hear about the engine failure, but glad you have found a replacement motor. I just did that dance a few months ago.

Soaringman

ya its great you still get to enjoy all your upgrades just with a new engine

LesField

Here's the damage.



Valve pushed into the head - ouch!



Damaged piston and broken sleeve.


On a positive note the new engine is having its IMS replaced and is being prepped for installation.

Flat6 Innovations

Did the valve seat fail? I can't tell from the pics, but this is the typical failure when this occurs.

The collateral damage probably hasn't stopped there.. Check that connecting rod for straightness and check the crankshaft for cracks.