V8 timing chain
 

The timing chain on my W140 (M119 motor, 131000 miles) rattles for a few seconds on the first start after an oil and filter change. There is no noise at all on all other starts, or while the engine is running. In the archives, there is discussion about rolling a new chain in. How is this done exactly, and where do you start? Do you start on the far right hand cam sprocket? Can it be done by one person? Assuming the original chain has no opening link, is there a particlar link that must be undone (drilled, filed away etc) or just any old link can be removed? I would prefer to remove the timing cover and inspect/replace other parts at the same time. If I go this route, does the chain still have to be rolled in, or can it be threaded in with the crank and camshafts stationary? Is part of the head gasket sandwiched between the timing cover and the cylinder head, or is there a separate gasket between them? Does the oil pan have to come out?

I need all the help I can get.

Thanks for your help.:)

Harry , if the timing chain is the source of your problem I would very strongly suggest that you leave this job to an experienced technician. I had one towed in that the customer tried to do himself and he bent the valves on it . Turned a 500.00 repair into a 2500.00 repair. Just my 2 cents;)

HarryM
 

Euro 287 is right on the money. I have installed dozens of timing chains before owning/working on Benzes and did not do my own until I watched a pro do it.

I agree with the assessment. Not for the uninitiated.

I would probably not have tackled my own (M117) if I hadn't had the opportunity to help out and get some hands on experience at the local shop. The shop owner was right in the middle of an M119 chain, when I stopped by, next thing I knew, I was hands on helping out (wifey was wondering why I was late from work ;) ). Not sure I would want to tackle an M119 at home by myself and I'm not afraid to tackle many jobs.

Yeah, pay someone else whose qualified in case something goes wrong later, you can hold them responsible...ie dealer or legit independent.

Don't forget the tensioners and guides!
 

Harry, don't forget to replace the timing chain tensioners and guides while you are in there. The M119 is a great motor, but timing chain, guides, and tensioners seem to be a common service item around your mileage.

I hear caps and rotors every 60K are a good idea as well.

you may also wish to read up on "racka racka" using the search

-fad

Harry,

I also had the opportunity to participate (mommy, can I help bake the cake scenario) in the replacement of my timing chains, rails, oil filter check valve and oil pump and its checkvalve while looking over the shoulder of my mechanic/friend.

While dismantling my old 2.7L 911 never alarmed me, this one does.

FIRST, GET THE CD ROMS! They provide great instructions. Missing something can be catastrophic.

(1) Unless you are a pro, I think it takes more than one person.
(2) Remember the engine has variable valve timing (I don't believe this is an issue unless you choose to freshen up the heads while you are in there, which I did).
(3) Be certain to lower the oil pan just a little, enough to allow the timing chain cover to clear on re-installation, or you will crack it ($800 part) (FOOTNOTE: THE CD ROM / WORKSHOP MANUALS DON'T TELL YOU THIS)
(4) Many recommend replacement of the timing chain rails (plastic) while you are at it to prevent an embrittlement failure with plastic parts then floating around near the chains (not good)
(5) investigate the condition of the wiring harness while you are in this far as the M119's are famous for the heat of the engine deteriorating the wiring harness.
(6) As others have pointed out, there is much available on this site, use the search function asking for "racka racka"

Not trying to scare you from these cars, they are INCREDIBLE,
but like anything there are areas to pay attention, and the above are some of those areas.

The old saying goes "Ounce of prevention or Pound of cure" is truly appropriate for these high end performance cars.

BUT YOU GOTTA LOVE 'EM

Good Luck

Dwight

i suppose it's time anyways(131k miles)to be changing your chains but i think you started this all because you heard a rattle IMMEDIATELY after you changed your oil.this happens as the oil leaves your top end via gravity since there is no oil to hold it up.probably a bad explanation but what you need to know is to prime the engine after changes in order to get the oil up there prior to engine running.i just went through this.do a search with my name and m.b. doc for the last week only(i think it's only 2-3 days ago).he mentions the crank sensor and from the diagrams i looked at it looks almost innaccessable

Unplug green wire going to ezl before cranking that is the pickup sensor wire.:D

euro 287...
 

can you tell me -as carefully as you can -what and where is my ezl?obviously it's an acronym of some sort.i went on alldata,did a search and nothing showed up.please,any help you can give would be most appreciated.TIA

what is timing belt change out mileage for 1993 500sel??? 90K?

My guidlines...
 

Timing chain/guide change intervals for MB M119 engine "In my opinion" are as follows:

100k miles - Really cautious
150k miles - Just about right
200k miles - You are on borrowed time

Ok the ezl is the ignition control unit mounted on the drivers wheelwell. It usually has a green wire ( but sometimes black) going to it from the crank sensor which is mounted on the bellhousing area on the drivers side near back of block. Anyway if you disconnect this wire at the ignition unit the car does not recieve fire cause their is no crank signal going to the control unit .That way you can spin the car over to build oil pressure after and oil change so you dont jump timing. On all older v8 motors dont go over 100k miles on the chain.ONLY use factory tensioner.I worked for an indi years back when I first started and they used aftermarket tensioners for a while . 6 out of 11 cars came back with jumped timing due to the tensioner failed . We called the others back in and put factories in all of them but only after we did 5 valve jobs and 1 engine job for free! I learned right off that you use factory stuff on alot of critical stuff on these cars .I have stuck with that since that day. On late model 119 motors I dont agree about the chains. If you change your oil every 3k miles like you are supposed to you wont have these problems. I have several customers who have 150k-200k on their 119 motors and we have checked for chain stretch with no problems found . On most late motors that have that much mileage when it comes time for any major engine work then I would agree to go ahead and do the chain then. The older ones are just a poor design and they will always fail after 100k miles no matter what.:D

Hello Euro287
 

I am about to replace the timing chain/tensioner and rails on my 92 400 E in 2 weeks, I have collected all the parts I need.

Unfortunately the new tensioner is not OEM, it was made by a Germany company, the brand is "SWAG". Is this the infamous aftermarket tensioners you had used? If this is the case, I'd better order one from MB.