BiturboBoy_V2.0_S3--

The serivice department (i called them up) My cam timing chain "skipped" and bent a valve on my engine upon impact!! Am i bsically screwed? or can they just replace the valve and it will be like new?? they said the insurance people are suppossed to be over to take a picture of the damamge when they pull my motor. maybe i'll get a whole new motor?? if i don't, is the engine basically handicapped even after they fix it??

Dustbuster

I don't know a whole lot about the Audi engine, but it sounds like an interfearance setup. This means that if something comes out of whack, you are going to get collisions. Questions is how much interfearance the engine has.

Your valve is FUBAR'd, obviously. I would be curious to know if it broke. If it broke, you are looking at both your intake and exhaust valves, piston, and combustion chamber needing work. Likely need the valve seat on the broken valve reground also. And depending on how much damage to the combustion chamber, you might need the head plained and decked. It's a lot of work to be done. But you said it was only bent, so you might just need new valves, a new seat on the bent valve, and a new piston. Combustion chamber should be good enough to work. Problem with a dinged up combustion chamber is flow characteristics are messed up and any work increases the volume of the chamber, lowering compression, etc.

What the insurance company decides to do is an entirely different question.

Hope the info helps.

BiturboBoy_V2.0_S3--

they said the valve was bent...so when they replace the valve, the seat, and the piston, will it be like new? or still a little different? obviusly the seals need to seat properly again, but other than that, if the valve was only bent, the engine should be good??

BiturboBoy_V2.0_S3--

the other car's(a van) left back end ata relative speed of around 15mph. i posted the entire incident a while back if you are interested i can dig it out and give it to you

BiturboBoy_V2.0_S3--

yeah..its the service department of Audi of Fairfield in CT...the best (i 've been told)dealer/serve dept. near where the accident happened...i live in MA, and was on my way back from a trip back to NY when i got into the accident in CT...i would go look at the damage...but with work and everything, its just TOO much time. was thinking about goin there this weekend(i'm going down to NY for the weekend), but they are not open on weekends i was told...so i may go on tuesday if i can afford a day off work.

VonK :: Retired

In that case all of the associated intake valves are equally mistimed and may all have had contact with the piston crowns.

The exhaust camshaft (which drives the intake camshaft via the timing adjuster) is driven by an external tooth belt from the crankshaft. If it skips or brakes, major valve/piston contact damage usually ensues.

I suggest you take a friend who has tinkered with engines to look at the cylinder heads and piston crowns when the heads are off. Minor gouges in the piston crown, must be smoothed out so no protruding metal can form hot spots that can cause pre-ignition. Probably, more than one valve/piston was damaged, and a valve job is definitely indicated for the affected head. When the job is done you should have full and equal compression on all affected cylinders. Tell them ahead of time you will want to see the compression test plots.

Dustbuster

Too bad they aren't open. I live in Boston and will be going back to CT for Limerock. Would have been an easy trip down to Fairfield to check out the damage.

Audi uses a 5-valve configuration, so I'll assume it's an exhaust valve that is bent. But the funny thing is that I would expect both exhaust valves (3 in and 2 out) to have been bent. Pistons come in tons of shapes: domed, grooved, recessed, flat, etc. Maybe the piston has a ridge only on one side, thus affecting only one valve.

Without inspection, you cannot determine how much it bent, etc. If it bent a lot, then the valve next to it was likely damaged. The piston is certainly damaged.

Now here's a question: Is it just ONE valve that was damaged? Did the engine shut off or die immediatly after the impact in the accident. If not, then I'd have the service place remove both heads and check all the valves and pistons. All it takes is four revolutions of the engine, and you have valves bent in more than just one place.

The rest of your engine should be A-OK. Crank, cams, etc. I don't think the valves are strong enouh to upset the cam - but might be a good idea to get it magnafluxed to see if there are any stress fractures (there shouldn't be but better to be safe, right?)

matthewk

I would have them replace the rod, both rod bearings as they we probably flat spotted. and if the valve chipped of a piece of the piston, check the cyl walls and the exhause track and the turbos.