2003 996 C4S Engine Failure - Coolant in Oil

[Nehmaiz]

Hi,

2003 996 C4S 146,000KM on the clock.

i haven't driven my car much this past year, only 4,000KM (2,500 Miles). I always maintain my car properly and change oil religiously...

while driving with the Porsche club, and without no temperature rise, i heard an explosion in the engine bay, the car stalled and the whole dashboard lit up.

when i opened the engine bay, coolant was all over the place... photos from the independent workshop show that the oil reservoir is filled with coolant... Hydrolock is suspected with all possible scenarios being gloomy...

would appreciate your input on previous similar experiences... could it be only a failed AOS and not a cracked head or engine block??

the workshop will charge me around 1,300$ for investigating the problem, which will not be charged if i decide to go ahead with a top end rebuild or whatever the diagnosis is...

Is it worth investigating now, or i can leave the car parked for a while without any consequences? Is the coolant inside the engine bay terrible in the long run? would it be impossible to clean out if left inside?

thanks,

Nehme

[g00sestepper]

Sorry to hear that Nehmaiz, I feel for you.

I am not a mechanic but found this on the web;

Hydrolock most commonly occurs in automobiles when driving through floods, either where the water is above the level of the air intake or the vehicle's speed is excessive, creating a tall bow wave. A vehicle fitted with a cold air intake mounted low on the vehicle will be especially vulnerable to hydrolocking when being driven through standing water or heavy precipitation. Engine coolant entering the cylinders through various means (such as a blown head gasket) is another common cause. Excessive fuel entering (flooding) one or more cylinders in liquid form due to or other abnormal operating conditions can also cause hydrolock.

Regards

Richard

[JFP in PA]

Hi,

2003 996 C4S 146,000KM on the clock.

i haven't driven my car much this past year, only 4,000KM (2,500 Miles). I always maintain my car properly and change oil religiously...

while driving with the Porsche club, and without no temperature rise, i heard an explosion in the engine bay, the car stalled and the whole dashboard lit up.

when i opened the engine bay, coolant was all over the place... photos from the independent workshop show that the oil reservoir is filled with coolant... Hydrolock is suspected with all possible scenarios being gloomy...

would appreciate your input on previous similar experiences... could it be only a failed AOS and not a cracked head or engine block??

the workshop will charge me around 1,300$ for investigating the problem, which will not be charged if i decide to go ahead with a top end rebuild or whatever the diagnosis is...

Is it worth investigating now, or i can leave the car parked for a while without any consequences? Is the coolant inside the engine bay terrible in the long run? would it be impossible to clean out if left inside?

thanks,

Nehme

Leaving coolant sit in the oil sump will destroy any possible future for this engine, if it even has one, so don't go in that direction. As these engines never blow head gaskets, you probably have either cracked a cylinder liner or a cylinder head. You need to have the problem diagnosed by pulling the spark plugs and dropping a bore scope into each cylinder to see where the engine has failed, or by simply pulling the engine and having it checked out on a stand. Realistically, the engine is going to have to come out anyway, so I would just pull it and find out if it can be salvaged.

[mcbit500]

Sorry to hear about your issue Nehme it's what we all dread. Were you able to establish the source of the coolant which was all over the engine bay? Blown out of the oil filler? Who is doing the work for you?

[Nehmaiz]

Sorry to hear about your issue Nehme it's what we all dread. Were you able to establish the source of the coolant which was all over the engine bay? Blown out of the oil filler? Who is doing the work for you?

Thanks Mcbit500... the car is at Alex renner motors (ARM) at the moment, he's still waiting on my decision whether to go ahead and investigate the failure or not...

honestly if the most likely scenario is that i have to scrap my engine, i prefer not to investigate where the failure happened and pay 4,500 AED (1,226$)...

According to ARM to fix a blown/cracked cylinder head will cost me around 65,000 (17,687$) to 75,000 AED (20,000$) ! A brand new engine from dealer will cost 144,000 AED (39,000$)...

it's such a dilemma especially when i love this car (2nd owner since new) and have driven it for over 100,000 KM in 5 years with no major issues at all...

[mcbit500]

Well at least its, in my opinon, in the best hands in the Emirates; some hard choices ahead. AED 144k seems a lot for a new engine though as most people on the forums are quoting $20k, which I believe I would stretch to, to keep my C4S on the road. I haven't had mine for that long but I'm already deeply attached to it. Good luck with Alex!

[Ahsai]

I wish you the best case of just a blown AOS and no engine damage.

[Nehmaiz]

Thanks Ahsai, unfortunately it's been confirmed today, after flushing out all the coolant and replacing it with new oil the engine does not turn maually ...

[txhokie4life]

Did they boroscope into the spark plug holes.

If that isn't turning over by hand -- might have a cracked cylinder wall.

If you had a hydrolock, the other possibility is a bent rod.

If this happened there is a good chance you can save the engine. It won't be easy to disassemble -- but if done carefully,

you might get away with just replacing the rod.

Of course you'll want to find the source of the hydrolock issue to begin with and replace all bearings as

antifreeze is caustic to softer metals.

thanks,

mike

Edited February 26, 2014 by txhokie4life

[Nehmaiz]

An update regarding the problem with my engine.

 

attached is a photo of the cracked engine block. the block was completely cracked throughout the middle.

 

I have no idea what might've led to this, I have since sourced an engine and fitted it into my car. the car is happily back on the road.

 

thinking of dismantling the old block to see exactly what went wrong, any good DIY on how to tear down the block?

 

Thanks,

Nehme

 

[318touring]

Wow that's crazy, I've never heard of a cracked engine block before.  You definitely want to find out how this could happen.

 

Where did you get the new engine, and how much did that cost you?

[Nehmaiz]

Wow that's crazy, I've never heard of a cracked engine block before.  You definitely want to find out how this could happen.

 

Where did you get the new engine, and how much did that cost you?

 

Exactly my thoughts when i saw the cracked block... i found a front accident 04 C4S in a scrap yard with an engine that has 18,000 KM on the odo.... snapped it on the spot for approx 5,500USD (block only)

[318touring]

Lucky chap (in a way).

 

Now, did you change the IMS bearing on your new engine?

[Nehmaiz]

Lucky chap (in a way).

 

Now, did you change the IMS bearing on your new engine?

yes updated to the 997 IMS bearing ;)

[Nehmaiz]

some more pics of the cracked block... 

 

[mcbit500]

I could only guess that you first had an issue which hydrolocked a cylinder whilst under power and the extreme force was transferred to the crankshaft which in turn cracked the crankcase.