nickcarguy

2000 , A6 Avant, 2.8 Tip, 161,000 miles. Original owner.
I'm about to do 2nd full timing belt service. Last TB service was done at 90,000. At last service Crank and Camshaft seals were dry and were not replaced. This time I have an ECS ultimate plus kit that includes crank and cam seals, just in case.
I've read postings about how removal of the crank bolt could result in spinning the crank pulley and destroying the key and keyway. This happens even with the crank pin installed. Something about the crank bolt itself corroding onto the sprocket. Blauparts actually suggests leaving the crank bolt & seal alone if there is no sign of leakage.
I'm assuming this has happened often enough for them to post this warning on their site. Have any of you had this happen?
If I do find the crank seal is weeping & needs to be replaced, is there any way to hold the crank sprocket to prevent it from spinning when I attempt to remove that damn bolt, that's been in place for 16 years.
Thanks for advice.

jcman

Leave it alone, I'm a firm believer that after a certain amount of miles and time accumulation fix and replace what only needs to be fixed and replaced and nothing more, because it's that more stuff that usually leads to the most problems like this excellent example of three parts made into one by a bolt that will never part.....good to know this.

CRuby

I read the same warnings which scared me a bit when I did mine for the 1st time. Did your kit include a new center crankshaft bolt? Manual says to replace these after removal. I recall they are torque + AOT bolts.
When you get car in service position, remove crank pulley bolts (#6) & look below the TB sprocket for oil wetness. If dry, leave it be. My car had ~140K on it when I replaced mine because of leakage. It's been a while, but I think I used the crank lock bolt to keep crank from turning. Used PB Blaster on center bolthead. Didn't use anything to keep TB sprocket from turning. 15/16" 12 point 1/2 " socket fit this bolt well I recall. 1/2 " breaker bar + pipe extension is needed, or impact wrench. Bolt came off with no problems. Key & keyway all looked fine. I reused key, along with new bolt. Some pics to help give you a visual. Crank seal is #2 part behind the sprocket (5). My pic for a 2.7, but I think this area is similar.

SloopJohnB@mac.com

I've had at least 3 TB services on our (sold) 2K4.2A6Q, at least one because the thermostat failed about 20K after the TB service. Never had a front crankshaft or rear crankshaft seal problem in about 190K miles. A 2K2.8 isn't worth that much that if you mess it up it will cost a lot to fix it.

If it's not leaking don't mess with it.

nickcarguy

Exactly what I plan to do.
But if it is leaking, I have to choose either leave it alone. Or remove the crank bolt and replace.
Thanks to everyone for the input.

Airbag

nooooooooooo touchie !!!!!!

signed ... Emperor Cusco !

Prospeeder

They just dont seem to leak. I would guess the cam seals are much hotter in the cylinder head and fail quicker. I for sure would do camshaft seals. You should consider doing valve cover gaskets, chain tensioners gaskets, and rear cam plugs at the same time. It makes cam seals a breeze, as you can just pull the bearing caps off. And the driver side chain tensioner is 100x easier to do with the rear timing belt cover off.

CRuby

Well, front & rear crank seals may be uncommon on our A6's, but I did have both leaking on my A6, with no leaks since they've been replaced. So crank seal leaks are still possible. My A6 experience is soley related to only this one A6 I have.
As with anything, if it ain't broke, don't fix it.

Prospeeder

Exactly in this case. I have only replaced one leaking 2.8 front seal, it was on a 210k mile car, and used regular oil its whole life, and had breather stuff broken for years. Rear seal can leak on anything, but never seems to be common on these. If you have them leak again down the road, be sure the breather system is working properly.

Airbag

a bit of a hijack ( sorry ) So what is the theory on seal leaks and PCV issues . if you are not venting the crankcase, the pressure builds up in there and forces oil out of the seals ? .