XSeries-forum

Gang

little while ago i noticed that first thing in the morning when i kicked my 4.6 up i had a rattling from the front of the engine..this rattle disapeared within 5/6 seconds and when warm and started you couldd not hear it..as if once the oil was all over everything it went.....

Spoke to my indy machanic and he said it could be timing chain tensioner...the sound was a little like a sproket over running when i reved her up...she would come out the rev but the rattling carried on for maybe 2 seconds after...bit like the sound on the barrel of a pistol when they check the bullets in the old western movies....

so anyway he changed the tensioner and after a few days it has come back...... he says it could be the chain then and that would be £1500 to sort....

when i picked myself up i thought i would write and get your thoughts...

its not rattling bad..its just in the morning for a few seconds it sounds like me tappits need ajusting...the indy guy said it will only get worse if its the chain and it will need doing before it cause bigger probs if it slips off....he lost me at that point but im sure you all know what he was meaning..

any thoughts as always gratefull received

lovlee...drummerboy 1

It sound more like your tappets are making the noise you described. How many miles has your car done?, when was it last serviced - miles and length of time.

You cannot adjust tappets on these cars they are hydraulic (possibly wrong spelling).

Drummerboy, your car has done high miles right? Around 180,000?

I would say that it isn't the chain, BMW advise to "check" the chain at 250,000. Chains don't stretch, nor do they just slip off sprockets / cogs. If your chain gives up, it would do exactly the same damage as losing a Timing belt. It could do this at any point from being new so I doubt this needs changing. I haven't heard of them changing one at my local dealers (my mate is Service Manager).

I would say its something else... are all your other belts / pulleys / tensioners ok? Some have rubber linings and these can wear which makes a noise when metal touches metal.

The other thing I think it could be is the starter motor. They have an automatic start switch on them... you turn your key and the starter motor engages, it doesn't stop until the car starts or you turn the key back to position 1. If it is not recognising that the car has started then it could just keep making a noise for a few seconds.


Turks.

Does the 4.6 have a vanos units as that is how I have heard that they sound when on the way out.

I reckon its either your tappets or the Vanaos unit. Is it only from one bank? Tappets are cheap to buy but expensive to change due to the amount of c*ap that has to come off to get to them. Or it could be the non return valves from the block to the head which are supposed to keep the oil in the tappet galleries when the engine is stopped to prevent them rattling on start up. I would seriously reccomend getting it checked to make sure it isnt one of the upper chain tensioners which are also a pain in the a*se to get to. BTW if the rattle does not go away, dont think that it will be OK to drive to the garage to get it checked out. See my thread 'How to overhaul your V8'. Yes its a 4.6, and engines are like rocking horse poo to find

drummerboy,

Above comments from others acknowledged & seem credible, (yes jas - vanos present).

Assuming your not fixing this yourself & will be paying to get it sorted then maybe seek the opinion of another garage & ideally & well recognised independent familiar with your engine type & symptoms.

Trouble is you may have to book it in as they are unlikely to diagnose from description only & will at least want to listen to the car - if only from cold you may have to leave it with them overnight.

If you do this think carefully who you use & consider trawling through This BMW garage guide courtesey of & credit to a fellow BMW enthusiast - John G.Burns

Fwiw it may be useful to identify an independent who has either worked on a 4.6is with similar symptoms or who is perhaps experienced at working on the Alpina B10 4.6 .......................this vehicle has near identical engine to the E53 4.6is (albeit B10 has a weaker head gasket to yours from the factory).

You may have to do some research, send emails, make calls (ideally communicating with any indy owner/proprietors). Hassle yes - but if you get it right it may save you time & money in the long run.

I give credit to other boards when due.......... To this end you need to be aware that there are quite a few 4.6is owners on xoutpost so maybe worth using creatively using the search facility on those forums too. (That site & admins/mods were very accomodating to us after our old uk site went down & I will never forget that).

Good Luck

Hi thought I would tap on to this thread as just had to put the X into my garage as making awful noise hard to describe bit between clicking vibrating sort of sound. Mechanic had a listen and reckons something to do with timing chain one side where the oil filler cap is. Just had oil and filter change done last week. first one done since had car [3months]. Its done 114500 miles. Mechanic reckons cost could be up to £1000 so hoping its not going to be that bad.Just wondered if anyone had any other ideas what it might be. Thanks Liz

I think its more likely to be the vanos unit as thats right next to the filler cap on the drivers bank (it is a v8 you are on about?). Go onto you tube and search for vanos problems, there a quite a few videos on there and you can hear the sort of noise it makes when it is on its way out. I understand that the v8 vanos units cannot be overhauled and you have to buy a complete unit (been there, done that). However the main chain tensioner is on the drivers side as well, so if that is on its way out it is fairly easy to get to.. The other two tensioners require a bit of work to change unfortunately

Thanks IanP, went on you tube and yes that is the noise that my car is making so I will tell my mechanic to maybe check that. Looking on the internet last night you can buy seal kits for the vanos as apparently this is what usually goes on them. Anyway I will keep this thread updated. Thanks for your help. Liz

Hi again, Where about is the vanos on the 4.4 engine, also my mechanic says that the back of the main timing chain is polished and is showing signs of wear..... Any thoughts please.... Also where is the best place to buy the vanos kits and the timing belt kits or are these BMW only parts. Hope someone can help Thanks Liz

Hi, if the 4.4 is like the 4.6 then the vanos units are on the end of each inlet cam. If your mechanic is interested then http://www.realoem.com/bmw is a good online parts microfiche for BMW. If you are going to change the vanos units then you may as well get the cam chains done at the same time as you are most of the way there anyway to get to the vanos units. The tensioner blades are not the best quality. There is someone called Dr Vanos on the internet who sells vanos kits, I couldnt get them for my 4.6, but the 4.4 might be different. The units are around £350 each from BMW I think. All my spares came from BMW as the 4.6 engine is not very common, but the 4.4 might be better. Good luck.