Engine mount (?) part number
 

Hi All

This is a photo of an engine mount (?) on my 2002 S8. It's at the front of the engine on the driver's side and is clearly in need of replacement! The photo is taken from the open bonnet. I have a little knock at slow speeds on rough road surfaces from around this area, so I suspect this might be the culprit. A proper description and part number would be most helpful. +++

Thanks, Jim

4D0199267 'rubber mounting', about £50 iirc.

When you change it, remove some shims from underneath the body bracket so that the bracket sits neatly on the top of the mounting. The reason it fails is that from the factory the bracket is shimmed to the right height but after 15 years all the main engine mounts have sagged so the engine sits 3-4mm lower than when it was made and it tears this mounting in half. Put plenty of penetrating oil in to the mounting bracket threads from above a day before you start since the bracket collects water and the steel bolts go rusty.

Thanks MJ. +++

Is it an easy DIY job to remove and replace it, or should I trundle down to my local Audi indy?

Its easy if you have the front end off. I would say the minimum dismantleage is undertray & bumper off and driver's side headlight out. You may need the front end in service position to get to the bracket bolts though.

Yep, a trip to my local Audi indy is due then. Thanks again. Wish we lived in the south-west!

Here is a couple of photos to give you a better view, when the front is off

Confirm MJ's part no (as if I would ever dare argue:tuttut:)

got my cam belt changed recently and this was gubbed on mine too, approx £60 from our sponsors, my tame mechanic fitted it in about 10 mins, and didnt charge me either, said it was included in the already hefty bill for the cam belt etc change+++

Was that a new one from A8 Parts, Brian?

No, was a used one, think a new one was around £87+++

I was planning to get mine done when the cam belt needed to be changed. But I only had it done 40K miles ago (January 2015) and, IIRC, the interval is 80K or 6 (?) years. I’d also planned to get the tensioners done (after MJ’s warning at the annual meet), but now I’m thinking I ought to bring this all forward.

Any thoughts guys?

I think I’ll go for a new one if that’s the case. Too much of a PITA to change it to risk a used one

I'd be disinclined to change the timing gear at half its life. One thing I would do as a 'while I'm in there' though is the hydraulic tensioner (077109479D) as this has the shortest life of all the components - particularly so on cars where the belt gets changed on age rather than mileage like most of our D2s now. I have five blown-up AVPs and that hydraulic tensioner killed two of them. The cam chain tensioner pads killed two more, and a broken valve spring did for the 5th. I've had a near-miss with the hydraulic tensioner on one other engine well before its belt interval so I always inspect that when the front end is off.

Spin the engine over by hand (clockwise) a couple of times using a bar on the crank sprocket. The belt should stay tight the whole time with no jumping about of the cam sprockets. If the cams are able to jump forwards and slacken the belt, change the tensioner.

Note - it is acceptable for the belt to be loose when the engine is stationary so don't panic if that is the case. If the engine stops in certain positions, cylinder compression can push the crank backwards which slackens the belt slightly due to the design of the tensioning mechanism (hence why its essential to never ever rotate these engines backwards). As long as the belt stays tight when its rotating clockwise then its fine +++ Obviously don't let the crank jump backwards when rotating by hand since that is counter-productive!

The INA branded tensioner is the genuine one with the Audi logo and number ground off, for half the price. 533003320, about £60 on ebay.

The other 'while I'm in there' job is to inspect the water pump. Check for any play in the pulley or grumbling from the bearing. Generally a genuine or good aftermarket pump will easily outlast the belt but its worth checking while its all in bits.

Thanks yet again, MJ. +++

Just so that I’m clear, as the belt isn’t due a change for a while (is it 6 years BTW?), would you advise that I leave it all alone until I am ‘in there’ for the belt change, or are the tensioners (I’m sure you remember the start-up rattle from the meet, although it’s never been so loud before or since) more urgent than that?

I would have a look at the tensioners immediately if not sooner. It sounds like the pads are wearing thin, and if they break up its bye bye engine. Pull the passenger side cam cover and check to see if the chain is wearing a groove in the pad. Its a pain, but it only costs a couple of hours labour and a cam cover gasket.

If the pad is ok (unlikely) then its the actual tensioners that are failing and ironically, thats less serious since they only rattle on startup rather than potentially destroying the engine. It turns in to a 4-figure job then though since the tensioners are >£500 each.

You may find, of course, that it still rattles after changing just the pads and in fact it was the tensioners all along. I had that with one recently which was rather frustrating. Its a £1000 gamble whether to just do the pads and hope it'll be fine or whether to just go for the tensioners and guarantee you only have to do it once. For me, I'll do the pads first for £20, but then its not a huge deal for me to have to do the whole job again. Annoying, but its less than a day's work. If you're paying a high rate for labour then it makes diving straight in with the complete tensioners less of a gamble I guess.

Find out what the tensioner pads look like and go from there +++

I have replaced mine twice with used part and I think it needs replacing again. Not sure if it's the second hand parts or my driving that makes rubber to rip off the metal base. At least I only paid £10-15 for second hand parts but might try new part and see how that lasts.

I have to say that I never noticed any shims so removing them could help in future as well if they are still there or they may have been already removed before my ownership.

They're often stuck on to the bottom of the bracket with corrosion :)

http://forum.a8parts.co.uk/attachmen...1&d=1536942268

With those shims/spacers, its almost as if Audi expected that torque mount separation to happen!


MJ, with the tensioner pads, are they doable en-situ, or do you need to remove the cam chain or inlet cam to replace them?

Both inlet cams have to come out, along with two of the cam caps on the exhaust. Right hand side you can do without disturbing the timing belt, but the left hand side sprocket has to come off to get the rear belt cover tinware off so you can remove the tensioner.