mumpsdba

Well I'm venturing into the Audi world for the first time. Typically I work on Volvos for a hobby and came across an 00 A6 4.2 quattro completely loaded that I couldn't resist. The timing belt slipped and the assumption was bent valves.

Bought the car and bought a replacement engine. I've removed the old engine (that was a treat - knuckles are shot) and have put the new engine in and am at a point where I plan to do all of the timing belt related maintenance before I button it all back up.

Here's my question (finally). In the course of removing the original engine I had manually turned the crank a few times. Just prior to taking the engine out I noticed that the T-Belt was slack and thought - well the tensioner is what must have gone bad on this and sort of just wrote it off. Turning the crank again tightened up the T-Belt.

So the new engine goes in and again I manually turned the crank (clockwise BTW) and everything lines up as it should. Well, I went out to work on the car last night and my heart sunk when I saw that the new engine's T-Belt went slack too (not loose enough to come off the cam sprockets but pretty loose). Things are still lined up but I'm scratching my head on this one - anyone know what's going on?

Also - when manually turning either crank (on the old motor and on the new) I noticed a clicking noise that seems to be coming from the left bank cylinder head side(s). Since they both have been sitting for a couple of months I'm hoping it has something to do with no oil being up there but thought I better check with the experts.

Thanks!

4Driver4

Too bad you didn't post this a long time ago.

Step one would have been to leak down test the old engine to assess damage. More often than not you can just replace a handful of valves instead of a whole engine. Wow.

It is not uncommon for the belt to go a little slack when the car is parked. Valve spring forces on the cam shafts can overcome the belt tensioner. When the engine is turned over, the belt should readjust.

Are you doing a timing belt service on the new engine, or just doing the old "the belt looks fine" thing and hoping for the best? If the latter, at least check the cam timing (using the tools, of course) before you button it up.

Don't worry about the clicking. That's the cam chain flopping around. It will stop as soon as you show it some oil pressure.

mumpsdba

Thanks I feel MUCH better now!

I went back and forth on pulling the heads vs replacing the engine. Honestly, without knowing Audis that well (except that you need a lot of specialized tools), I thought I might getting over my head pulling the heads and going that route. Now that the engine has been replaced I plan to dive into the other engine and take it apart - if nothing else it will be a great learning experience. And I'll have a spare engine ready to go (maybe :-)) or I screw it up and it makes a nice coffee table/parts store in the basement.

The other motivation for the replacement engine was that it had 69K on it as opposed to the original which had 110K. Price between having the heads sent out and fixed vs a replacement engine wasn't a huge difference.

I'm doing everything that comes in the Blauparts timing belt kit (cam seals, w/p, tensioners, T-Belt etc) and am also doing the valve cover gaskets. I did the rear main on the new engine before putting it in as well (it was dry but better to do it now than later :-)

It's such a nice car. I'm having a great time with it so far. Thanks for your input - much appreciated!

Steve.

4Driver4

Just make sure you use the tools to do the belt. Cam sprockets are not keyed to the shafts; timing is infinitely adjustable. You need the tools to get the cam timing right.

mumpsdba

I'm renting the tools from Blauparts as well.

2.7Lturbo

blau is a good parts place, they will hook you up nice