Weird clanking noise from engine all of the sudden...

[maverik259]

So replaced by battery last week becuase i killed it...then 2 days later my car started making a weird rattle in the engine bay at start up or anytime the engine was under heavy load (aka on the verge of stalling etc) it never makes a noise any other time while on or shutting down, or really even revving...but mostly when turning on...after sticking my ear down in it while my roommate started her for me a dozen times, it seems to be coming either from the supercharger or the rectangular tube that leads form the IC to the supercharger... I dont htink its my SC since it doesnt make any sound when just running nor does it give me any issues while driving etc...not feel of powerloss either...my roommate said it sounds like an air thing, almost like cavitation or something similar... any ideas? I've also hooked up my OBDII reader and the only things popped are my coolant below thermostat temp (again, despite me replacing the damn thing 2 years ago), and a serial communication link malfunction thing...but i have no CEL on the dash

To remove this ad, register today or login if you already are registered!

[Hogger]

Change your timing chain RIGHT NOW!!!
DO NOT drive it. You don't get much warning with these.
Ask me how I know

[maverik259]

how do you know if your timing chain is bad? and is that a DIY thing?

[Hogger]

You will hear a rattling/clanking sound for a second or two at start-up, then it will go away once the oil pressure builds up.

It can be a DIY, just depends on when you catch it, and how much damage has been done. At your stage, it would be pretty easy, assuming the chain hasn't jumped teeth on the sprockets.
I did mine, but I had to replace the head because the chain jumped teeth, and bent valves.

The problem is that the M271 uses a single gang timing chain, and the chain stretches which leads to this rattling sound, then jumping teeth and doing lots of damage. Some have gotten away with just changing the chain, others have gone as far as swapping the whole engine.

[maverik259]

ugh i hate you! lol that sounds exactly what the issue is...ive been driving on it for about 4 days now...i guess i'll stop...a guy gave me the number for an indy shop downtown that I havent used before but he said the guy used to build M3 out of 335 from scratch and his skills with MB isnt too far off...so hopefully he can help...

just sucks cuz ive been in the process of trying to sell my car and buy a c55...just another expense i dont need right now!

[Hogger]

LOL... Sorry.
Shouldn't be too hard if your mechanically inclined.
Pull the valve cover, pull the top timing chain cover. Break the chain, attach new chain to old one. Feed it around by manually turning engine around. Link new chain, and replace covers.

That's the super simplified version, but pretty close to what it entails.

Including myself, there were a few others that had the same problem about a month ago, there were a few thread about it.
If you decide to tackle it yourself, I can help walk you through it.

[maverik259]

ok cool...you remember what it cost you in parts and where you got em from? did you end up replacing both chains and the valve seals as well?

[sammydragon3]

what would probally be good for the rest of us if u made a video of the noise

[Hogger]

A good way to check is to pull the covers, and you'll see the sag in the chain. That will be the tell tail sign.
If you don't have any bent valves, you should be able to do it for about $300. I got my parts from genuinemercedesparts.com. You should only need a chain, tensioner, and a new valve cover gasket set. The upper and side guides might not be a bad idea to swap out too since your in there, so maybe add another $40.

Mine was $1700. I changed both chains, all guides, new head with updated valves, guides, and springs. Plus other little maintenance parts, some that I broke taking it apart.
My damage happened on startup. It jumped teeth while cranking, and then wouldn't start, so I bent most of the intake valves.

[LILBENZ230]

Good call, Jordan. It is hard to get the emphasis across sometimes on the forum how critical it is you do not continue to drive. Your $300 repair can literally be 10-15x as expensive within a second when the chain slips.

Maverick listen to Jordan. You don't want to drive it not one more foot. The OEM chain can be had for $52 from RMEuropean, the tensioner (which you also need to replace) will be $77. I was quoted $260 in labor.

[Hogger]

Thanks.
I knew the chain was cheaper somewhere else, just couldn't remember where.

[nlpamg]

noooooooo! sorry to hear this man. how many miles do you have on your car?

[maverik259]

about 87k...and ok sweet, ya i'll take a video of the sound in a few minutes if that would help, but im quite confident you are correct hogger (although I dont want you to be)...but ya i'll start looking the parts up now and see how soon i can get them in here, and then hopefully you'll be able to run me through it as best you can...im gonna have my roommate and another forum guy (MBfinatic) give me a hand...3 heads and 6 eyes are better than one!

[maverik259]

so the only parts I'd need are, the chain, tensioner, 3 guides, and the valve cover gasket...no o-rings or anything...also will i need to drain the oil down? or should it be free of sitting oil at the top like that?

And the other chain you replaced...is that the "Balance shaft chain"

Do i need to replace that too or is that just a lot more work than is necessary?

Also last but not least, do i need to get a tool to break the chain, and connect the new chain?

[maverik259]

and of course the chain is $50 from rmeuropean and sold out but $190 from every other site!

[maverik259]

Ok so i ordered all the parts from the Atlanta dealership for under $150 (well everything minus the timing chain)...im waiting till RM opens in like an hour and im gonna find out when they're gonna get it back in stock...if its a week I can wait cuz then i can just pull my engine apart and do everything but the chain and at least be ready when it gets here...but if its longer then im probably just gonna have to bite the bullet so i can get this done and have a vehicle again!

[LILBENZ230]

http://www.autohausaz.com/search/pro...=W0133-1786813,

[LILBENZ230]

I bought the chain from there this morning and the tensioner from getmercedesparts.com this morning. It looks like I'll still have to buy valve cover gasket. Not planning to replace balance chain (never heard of an issue here) or guides.

Is the valve cover gasket necessary?

[maverik259]

so just called RM and the guy was pretty clueless, and told me to just check back again in a day or 2 and if its still not listed as in then call him back to find out when it will be in...really?! lol wow

[maverik259]

Originally Posted by LILBENZ230

I bought the chain from there this morning and the tensioner from getmercedesparts.com this morning. It looks like I'll still have to buy valve cover gasket. Not planning to replace balance chain (never heard of an issue here) or guides.

Is the valve cover gasket necessary?

awesome thanks for hte info...just bought it from them...how do you plan on breaking the chain?! the guy from RMeuropean funny enough tried to tell me to use a bolt cutter...hahaha

[LILBENZ230]

I won't be doing it, so I don't know.

[04mbc230]

Originally Posted by maverik259

awesome thanks for hte info...just bought it from them...how do you plan on breaking the chain?! the guy from RMeuropean funny enough tried to tell me to use a bolt cutter...hahaha

Hmmz.. I am intersted in the video as well. Can you make one and with the sound.

As far as if you want to do DYI, there was a post somewhere in the forum that someone did a DYI on this.

[LILBENZ230]

I would not attempt to start/run the car for video purposes. I mean it would be cool and all but not worth the risk, IMO.

[04mbc230]

Originally Posted by LILBENZ230

I would not attempt to start/run the car for video purposes. I mean it would be cool and all but not worth the risk, IMO.

Ok.. I agree. How about in the name of research and the greater good for all owners to define this issue?

Then again, better not.

[Hogger]

I wouldn't start it for a sound clip. That could be the detrimental start that does damage. You typically don't get much warning from when you first hear the rattling to when major damage is done.

Sounds like you got all your parts. I wouldn't think you need the balance shaft chain. It is a lot more work to get to, and probably not necessary in your case.

If you have a Harbor Freight near you, go get a chain breaker, it will help you re-attaching the chain too. If no Harbor Freight, an auto store should have one, just more expensive. Attaching the chain can be a little tricky. MB sells a special tool for it that costs about $250. I modded mine with a bolt to pressed the pin head down, and did a little minor "peening" to it. I can show you that later, and walk you through it.

No problems cutting the chain with bolt cutters. That's how I cut my balance chain. Just wrap the cutting area with duct tape in case small pieces come loose the tape will hold them. But the chain breaker does a good job too.

The valve cover gasket is a good preventative maintenance item. It should come in a kit that includes the 4 spark plug gaskets that go around the plugs. I know a lot of people here have had issues with those leaking oil down into the plugs. I had oil in there too.

Take a look at my thread here
Timing chain and balance chain replacement. That should give you a lot more info, and help you out a little.
When you get there, I'll have to post you up a picture of removing the guide pins. It's easy, just a little confusing when I read it. The pic should help describe it.

Good luck!