Assessment of valve damage after timing chain failure

Last week on my way home from work my timing chain snapped and my car shut down. I didn't hear any crunching banging or popping noises. I would like to assume that the valves had not been damaged because the engine shut down so quick. I have the timing chain and tensioner out, valve cover off, front timing belt cover off and ready to install new parts. My one concern though is pulling off the head to inspect the valves and I'm curious if there is a way to check to see if the valves were damaged without pulling off the head. I've searched around on the internet a little bit and I haven't found much information to make me feel comfortable enough not inspecting it.

As always, your input is greatly appreciated!
2005 audi a4 2.0t b7

Yes it can be done..........NOT VCDS related though........

"Lock" crank at halfway point to protect valves and from pistons hitting.

Take regulated compressed air and feed into spark plug hole with reverse compression tester tool & manually rotate cams till lobes face up for respective cylinder.

If air is not maintained for a seal and air can be observed in the intake or exhaust you are screwed with repair being self-evident to tear down.

There you go again, Jack! Being right there when we need you! Thank you!

I'm assuming the timing belt is going to need to be removed for this?

Chain snapped so...........I would.

Perhaps this wasn't the best idea but in an attempt to check the valves, I pulled the spark plugs and slowly turned the crank and tried to listen for any tap or tick while rotating and didn't hear anything with my mechanic stethoscope. In hindsight, if the valve was damaged after the tc failure, there wouldn't be a tick because the valve would have already been bent and wouldn't make any further noise.

Is my logic correct or should I just go buy a pedal bike and forget my quest of never paying a mechanic to work on my cars?

Ok well this will be my next step then.

Could you also point me to a DIY of re-setting the timing without the cam locking tool? My observations have been that the tool only gets you "close" to 0. Perhaps your opinion on this?

Thanks again, Jack! I am very grateful for your time and expertise!

Moving to General VW/Audi Repair.

-Uwe-

With boro scope camera check the top of all the pistons for a strike mark. Also what jack mentioned

Perhaps this wasn't the best idea but in an attempt to check the valves, I pulled the spark plugs and slowly turned the crank and tried to listen for any tap or tick while rotating and didn't hear anything with my mechanic stethoscope. In hindsight, if the valve was damaged after the tc failure, there wouldn't be a tick because the valve would have already been bent and wouldn't make any further noise.

Is my logic correct or should I just go buy a pedal bike and forget my quest of never paying a mechanic to work on my cars?

Ok well this will be my next step then.

Could you also point me to a DIY of re-setting the timing without the cam locking tool? My observations have been that the tool only gets you "close" to 0. Perhaps your opinion on this?

Thanks again, Jack! I am very grateful for your time and expertise!

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"No way Jose".......... and it's not something I would rig ......please RTFB and JPPSG.

I'd want to know if oil PSI was the cause of this chain snap and check cam lobes/bearing journals.

Take pan off and inspect sump is advised.

Was car missing before its failure and where is your auto-scan?

Jack's method is spot-on as usual.

Another method is to pop the intake manifold off, set the crank and cam positions as Jack mentions above, then pour some liquid (light oil or something similar) into the ports. If it ebbs away into the cylinder - you know the valves aren't sealing. However, if it had happened to me, I'd need to know why the engine dropped the chain, be it loss of hydraulic pressure as Jack says, or something like the tensioner guides wearing out. Saying that, the guides will probably be mangled after the dropped chain so are going to need replacing anyway.

It always gives me a squidge in my stomach when I read stories like this...

Sorry for not following protocol.

The car is 75 miles away and I'm leaving for FL in the morning so I can't get a scan until I get back.

2.0t bpg engine with 224,000 miles, in which I've put on 100,000 of. Bone stock with all GAP with the exception of motor mount and front suspension kit from Dolphi. M1 0-40 every 5-7k with audi filter. I went 10k between on accident about 15k miles ago and vacuum pump and oil filter housing gaskets started leaking, or perhaps coincidence. I replaced said gaskets, cleaned the valves, replaced IM gasket and TB gasket too. I have no record of the TC or tensioner being serviced.

100ish miles ago the ticking got louder so I changed oil but this time I used the best Fram filter walmart had due to the dealer closed on weekends. Seemed to have made it a little quieter. I did notice some metal shavings on filter which I've never noticed before.
Drove the car to work on monday and when I pulled up to work I noticed the ticking got much worse. My LUNCH I headed 1 MILE away to get food. Upon acceleration I noticed a slight hesitation and then the motor shut down as if I turn the key - no pops, clicks or snaps.
Towed the car to my parents house and started dissecting the motor. Once I got the timing cover off, the tensioner guide was in two pieces and chain obviously snapped. The guide was clearly warn down so far the chain had been riding on the metal shaft.

I should have trusted my gut and changed them both out last summer but was told "that's normal. Get used to it cause 2.0t's all do that" by a indi euro mechanic. Also seem to get that same response from most people on various vag forums.

Please let me know if I'm leaving any info out that might be pertinent.

Thanks in advance!!

I'm not sure why anyone is asking you for a scan. You know this engine is mechanically damaged. A scan strikes me as relatively pointless at this time.

-Uwe-

Indeed, can't see how a scan would help in this case.

At that mileage and given the chain snapped I would advise removing the head as you'll never be sure otherwise plus, it could really do with some attention to the vales etc. anyway IMO.

One thing is for sure a scan won't hurt you at this moment.

Unless it's pirated

ivagp said:

Unless it's pirated

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Since the OP is a Verified User, I have no reason to think that.

-Uwe-

oops sorry op