Attn. all Chain Warriors, I need help removing rear timing cover

[gcoy]

Hi,, I have ran into my first delay in doing my own timing service.
I removed the upper covers with no a problems. Now I can't break loose the middle, large cover. I have removed all of the bolts. Is there something that I am missing? Is the main seal holding me up? I am moderately hitting the cover w a rubber mallet but it wont budge. Thanks

[BCsniper]

when in doubt.....get a bigger hammer

[gcoy]

ha! Love it... I have no problem with that, being from Idaho and all.

I have had full confidence in pulling my motor and getting to were I am now.

From this point forward I am getting very nervous and cautious.

I just wanted to make sure that I don't need to worry about the main seal. Will it slide off with the cover??

[EUROSWAGR]

Make sure all of the bolts are out, do you have the manual to refer to?

There isn't a middle cover, only upper and a lower so make sure all of the bolts are out of the lower cover.

Word to the wise, replace the main seal while the motor is out and after you install the cover during reassembly and if you need the tool PM me because I just used to to replace my rear main.

Here is a picture of all of the bolts...there are a lot of them...30 just for the lower cover

[gcoy]

Yes, Got it off. I did have all the bolts out, I just needed to pry a little more. Then POP off it came.

Wow!! I'll post pictures later and show you what I'm up against... Thanks, I will need the tool to replace the main seal,,

[gcoy]

First off. The reason I am doing a timing service is because I am getting miss fires ALL on bank #1. 1 thru 4. So I new I had a problem with bank 1 and I was thinking it is a Cam Adjuster problem.

But Now I need your opinions...



Ok, So after removing the timing covers, This is what I see.



Looks to me as though the upper Tensioner guide broke and (somehow) kicked the chain nicking the timing cover.

Now it looks like the timing is off as the two cam shaft nuts at the front are not lined up. Plus the lower left chain guide is broken.



What do you guys think??


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[gcoy]

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[EUROSWAGR]

Time to pull the head man, see if you have any valve damage because that bank looks pretty out of time.

[gcoy]

My leak down test passed just before I pulled the motor. Doesn't that rule out valve damage ?

[EUROSWAGR]

My leak down test passed just before I pulled the motor. Doesn't that rule out valve damage ?

I don't see how the cylinder could have sealed properly with the cams out of time. Who did the test?

[gcoy]

The dealer, Audi of Boise .. pretty sure my Indy mechanic said his test passed too... I'll ask him tomorrow.

[liloldbie]

It looks only a tooth out of time... I would definitely double and triple check your leak down and compression. If results are bad, retime, reassemble and check again before you go pulling anything.

[rocket5979]

I don't see how the cylinder could have sealed properly with the cams out of time. Who did the test?

You can pass a leakdown test if the intake and exhaust cams are out of time from each other. There is a large duration gap (2 of the 4 cycles) between when the intake valves have closed and when the exhaust valves open back up after the compression stroke and combustion where everything is closed. They would have to be pretty far out of time with one another to get to the point where they don't pass a leakdown.

[gcoy]

Were is the rest of this tensioner guide? It must be in the bottom of the oil pan.. What problems can this cause? Thanks

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[cheetah993]

It is in the oil pan, and in the oil pump screen and the dust is in the filter and remaining oil in the engine. When I did mine, I took the oil pan off and made sure to get all of the bits of guide out that I could. It also looks as though you are off about as much as I was when my center guide (yours is cracked) broke in half. I just put it back to the correct timing (move the cams enough to get the tool in place) and checked my timing a few times and turned the engine by hand before I put it back together My advice, take the oil pan off and clean it out, and take the valley gasket off the top and clean the oil out of there and it is a good time to replace that gasket since they are known to fail. If you need a reference here is my write up when I did mine. Also feel free to PM me with any questions.

http://www.audizine.com/forum/showth...Engine-Removal


As for problems it can cause having it in the engine... Well it is foreign matter that is extremely hard. Scoring journals of the crank, piston walls, and the fact that the dust can act as a sand blaster needless to say it is not great. You need to get as much out as you can, and change your oil within about 2-3k miles after you rebuild the engine to make sure you get it all out.

[gcoy]

Thanks Cheetah, so your timing was off as much as mine looks to be? It really looks like the chain skipped a gear with the damage to the timing cover. Can a leak down and compression tests be done w the motor out? Sorry I'm learning as I go here. lol

[cheetah993]

It appears to have been. Mine did not mark the cover up at all due to how the guide broke, but it was definitely off quite a bit. The tests would be hard to do but could be done since you need to crank the engine over (put the starter back on) and supply 12v to that to crank it and get your readings. Did you ever burn a lot of oil?

[gcoy]

Ummm. Good trick w the starter. This motor always did pretty good on oil. Burns about 3/4 qt every 3k miles. This motor has 112k on it. At some point I need to consider looking for a replacement motor. JHM has one but I see spending around $5500. Hmmm

[rocket5979]

As for problems it can cause having it in the engine... Well it is foreign matter that is extremely hard. Scoring journals of the crank, piston walls, and the fact that the dust can act as a sand blaster needless to say it is not great. You need to get as much out as you can, and change your oil within about 2-3k miles after you rebuild the engine to make sure you get it all out.

Not likely. The screen on the oil pickup tube will stop the bigger stuff, and then the oil filter will do the rest before allowing the oil to flow to the rest of the engine. There is no way for the bits of plastic to come into contact with the crank journals short of the oil filter completely failing, which would be unlikely.

However, if a large enough piece of that plastic gets sucked into the screen at the end of the oil pickup tube then it can cause a lack of flow to the oil pump due to it pulling a higher vacuum, thus creating really low oil pressure after the oil pump which would in turn wreak havoc on your entire engine. That would be due to insufficient oil pressure that would cause scoring to the bearing surfaces and potentially result in spun bearings if they got heated up enough and welded themselves to the crank or camshafts.

Regardless of how or why the damage would occur, it would be prudent to remove those bits while the engine is out. Why get lazy when it will only take maybe an hour tops to do the job while mozying around drinking a beer while doing it. While the engine is out I would do a full inspection of everything I could see. You never know what else may be hiding. After all, it is considerably more easy to troubleshoot and fix minor problems on an engine when it is on the stand out of the car than when it is tucked in deep between the fenderwells with everything else in the way.

[gcoy]

So, my plan of attack will be:



Pull the oil pan and clean all plastic from the broken guide.

Take the valley gasket off the top, clean, and replace.

Set timing

Replace guides and tensioners.

Put everything back together



CROSS my fingers and start the motor.



Thank you everyone for advice, (Cheetah, I'll pm you as I have a couple quick questions.)

[cheetah993]

Sounds good and good luck!

[Omerta]

Pull the plugs and throw a borescope into the cylinders to see if there is any piston/valve contact evidence if the timing was off by that much.

[Dirtracer603]

You don't need to pull the head to check the valves (borescope) and the only issue you have to worry about with the pieces of broken guides are if they get wedged somewhere critical (timing chain & gear). You really don't have to worry about 'every small piece' either, they will either drain out with the oil or get pulverized during the mechanical processes of a running motor. There's already a lot of stuff floating around our higher mileage motors (flaking paint from within various covers of the engine).

[JimmyBones]

when in doubt.....get a bigger hammer

Oh man I wish that I had a drawer for just my hammers and pry-bars! The Jimmy drawer!

Too bad the drawer would have to be one of the top drawers because my biggest pry-bar is about five feet long.

[ProtoFly]

This is the exact failure that my A6 has had, including the skipping one tooth. I pulled the head, and found evidence of light piston to valve contact on the exhaust valves. I opted to purchase a set of lower mileage heads, since my car has 175k miles on it.

You might want to get a camera in there to check for any evidence of contact as well. (sorry to be the bearer of potentially bad news)

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[gcoy]

Well. my fingers are Crossed!! I have almost everything back together and hope to start my car this evening. My mechanic did a leak-down before I pulled the motor. He said the leak-down passed with flying colors and does not think that I have valve damage.. I guess we will see....

[ProtoFly]

I'm quite anxious to hear of your success!

I'm awaiting more $ to order up all the timing parts. Did you end up replacing your adjusters? Any 'gotchas' on the reassembly and timing sequence?

I'm really hoping that Audi updated some of the components, but then again, I suppose I could be happy that I reached 175k miles without major incident on mine. Still, these plastic bits that fail are not comforting. I'm not even sure that the actual tensioners go bad, as they are really simple hydraulic tensioners. (I'm still replacing mine, though...)

-Darryl

Well. my fingers are Crossed!! I have almost everything back together and hope to start my car this evening. My mechanic did a leak-down before I pulled the motor. He said the leak-down passed with flying colors and does not think that I have valve damage.. I guess we will see....

[gcoy]

YES!! It started!!!

I am so relieved and happy. What a project this has been. I still need to put the axles, cat-back, and bumper on. The car fired with No chain rattle. I cant wait to drive my car, its been 4 months.

Thank you Cheetah for all your help and everyones advice!

Protofly pm me. I would be more that happy to help you out.

[cheetah993]

Gcoy glad to hear it all went well! There really is no better feeling then when it starts for the first time and does not have a rattle! Now just think of the money you saved yourself as well and it really should make you happy and proud that you did it yourself.

[ProtoFly]

gcoy, did you end up replacing your adjusters? Or re-using the existing?

Glad to hear of your success. I'm cleaning up my engine this weekend, in prep for the heads, which came in yesterday, along with the new head gaskets and bolts. Then I can start the re-assembly process - well, once I have the $ for the timing components.

I've got two sets of adjusters, and will pick the best of them for reassembly. Honestly, the one I disassembled from my engine with 175k miles on it doesn't look bad at all, but the other set I have is from a 77k mile engine (with the heads), and I'm hoping they are even better.

[gcoy]

Yes, I did replace the cam adjusters with new ones. If you want. I could post my parts list with part numbers. It has everything you need to put the motor back together. Do you have the tools needed to set the timing?

[ProtoFly]

I'm pretty sure that your parts list an mine would be different, as I have an A6 with the 4.2. Yeah, I can't tell the actual difference in the engines either. Same output, same complicated chain system. And probably most of the parts are either the same, or have superceded/updated to be the same. But, if you feel like sending a PM with the parts list (maybe prices you paid?), I'm interested in comparing.

ECS Tuning has a kit for the S4 4.2, and a different kit for the A6 4.2, but they don't list the part numbers included in the kits, so hard to know what similarities or differences there are. That's actually one reason I haven't purchased the kit from them, as I don't know what specific part numbers it comes with, and therefore don't know what it -doesn't- include that I'll also need.

Money is tight, so I'm likely to shop around for the components, as I have noted radically different pricing on some things. Head bolts, for example: Some places charge up to 11 bucks each. I bought a set of 20 bolts for $32. Head gaskets: Some as high as $110 each. I paid $42 each, same gasket (Victor Reinz). (ECSTuning had the best price on those BTW).

There were also a few web sites that had good prices, but their online stores were so convoluted that I didn't bother ordering. No excuse for poor web programming these days, especially if you are running an e-business.

I started cleaning up things, which is proving to be a long process. Maybe more progress this weekend....I sure do miss the car. My Volvo just isn't the same....

-Darryl

Yes, I did replace the cam adjusters with new ones. If you want. I could post my parts list with part numbers. It has everything you need to put the motor back together. Do you have the tools needed to set the timing?

[EUROSWAGR]

Protofly, if you haven't already checked..I got parts from genuineaudiparts.com, partsgeek, and rock auto. Also I would suggest buying a copy of ETKA off of eBay, it is money well spent and looking up part numbers for reference is much easier than trusting forum members to be 100% accurate.

One thing that would worry me is the quality of the head bolts you purchased..some things aren't meant to be deal makers. What I'm saying is it isn't hard to make a bolt with the same thread and specs out of any type of metal, but if those cheaper bolts don't have the strength your gonna run into a huge headache that will cost way more money in the end. I'm not sure if you've looked up head torquing procedures yet, but you will be surprised how hard the last 90degree turn is during final torque...I'd hate to have one of those bolts snap off in the block.

[ProtoFly]

The head gaskets and bolts were sourced from ECSTuning, who I believe to be a reputable business. I'm really not concerned with their quality. Some of the other sellers, yes, I agree, could use counterfeit sub-par bolts. And yes, I've looked at the torquing procedures, that last 90 degree turn is what 'yields' the bolt, and what allows it to never need re-torquing. Good stuff.

GenuineAudiParts and RockAuto are my sources for many things. I do have an older copy of ETKA, could probably use a later update that might have superceded part numbers though.

Thanks for the concerns. I like that this community looks out for each other.

-Darryl

Protofly, if you haven't already checked..I got parts from genuineaudiparts.com, partsgeek, and rock auto. Also I would suggest buying a copy of ETKA off of eBay, it is money well spent and looking up part numbers for reference is much easier than trusting forum members to be 100% accurate.

One thing that would worry me is the quality of the head bolts you purchased..some things aren't meant to be deal makers. What I'm saying is it isn't hard to make a bolt with the same thread and specs out of any type of metal, but if those cheaper bolts don't have the strength your gonna run into a huge headache that will cost way more money in the end. I'm not sure if you've looked up head torquing procedures yet, but you will be surprised how hard the last 90degree turn is during final torque...I'd hate to have one of those bolts snap off in the block.

[JimmyBones]

I'm not sure if you've looked up head torquing procedures yet, but you will be surprised how hard the last 90degree turn is during final torque...I'd hate to have one of those bolts snap off in the block.

They make longer breaker bars and 3/4 drive ratchets for that. A long length of pipe/cheater bar works too. Plus it makes a good beating stick.

[ProtoFly]

Protofly, if you haven't already checked..I got parts from genuineaudiparts.com, partsgeek, and rock auto. Also I would suggest buying a copy of ETKA off of eBay, it is money well spent and looking up part numbers for reference is much easier than trusting forum members to be 100% accurate.

I'm being quite unsuccessful at finding the ETKA 7.3 or 7.4 updates/installer anywhere, not even FleaBay. Anyone have it on here? I'd much prefer to have the updated part numbers for the timing bits....Realizing I'm posting in the S4 section and my car is an A6. It's just that it seems like the S4 people are more likely to DIY...

[EUROSWAGR]

They make longer breaker bars and 3/4 drive ratchets for that. A long length of pipe/cheater bar works too. Plus it makes a good beating stick.

I know, lol, but I managed just fine with the breaker bar I had...I actually use my jack handle as an extension to get a little more torque so I don't bust a nut straining