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Just a few days before x'mas 2016, my c230 coupe broke down because of tension pulley shattered into pieces then serpentine belt follows.
Actually 7 days before that happened, I already ordered Idler/ tension pulleys and serpentine belt from dealership.... but just 1 day before I can get those parts, it failed.
Yep, I know nothing new to all members here..... just pulley and belt change.
The best is yet to come......
Before the car broke down, it was running smoother than most other cars. so I expected just changed the belt w/ pulleys then it should go again.
I fired up the engine and it was rattling like a bull and at least 2 misfires banged from the exhaust!!
Even though I have no experience to fix any 4 wheels before ( only fixed own motorbikes ), I knew something went really wrong with it. I turn it off and dig into the internet..... then I found this site!
There are a few posts about the M271 timing chain problem.... with the really "UNUSEFUL" Haynes manual in hand.... I decided to pop open the cam cover and take a look.
Confirmed it was 1 tooth off at the intake side. But it is hard to tell how bad was the chain and tensioner. Then I just removed the cover and the moment both cams jumped quite a bit.
So I decided to do the fix by my own..... The cheapest quote for the job is C$2000 and parts are not included.....
Last edited by solarwindp; Feb 15, 2017 at 04:54 PM.
I ordered a set of febi timing chain kit it came with everything and most importantly those are closed loop chains. I don't need chain tools to do the job. It also eliminated the possibility of chain clip fails.
The bottom chain and the guide rail of the right side is not possible to change if I am not gonna to pull the oil pan/ cylinder head off.
Line up the timing mark was easier than I thought.... well..... When I try to put the front cover back on...... *Sh*t* happened.
The head gasket warped and I cannot put the cover back on. And I noticed that there are RTV everywhere.... it seems to be someone did something with this engine before. So the head gasket thing seems to be some sloppy guys job.
Alright...... Head gasket and head bolts + another 4 days of parts waiting.
Pull the engine apart, the cylinder head, engine block looks good.
So clean it up real good and try to put it back..... And I realized that one of the head bolt give false reading at the last 90 degree torque.... maybe it was -20 deg ..... but I was kinda tired and just put it back ......
(yep... I was thinking about sell it away after put all things back.)
Bravo freaking zulu, man...(that's Navy for outstanding)
What a journey....that lower timing cover is almost impossible to remove and re-install properly without pulling the head. I steered clear of it when I did my chain. This thread will be valuable to those aiming to tackle this in the future. It also proves what I've posted on here before, that the timing chain job very DIY-able, no need to pay someone $$$$$$ for it. Unforseen snags like the OP exerienced are what bring on the headaches...
Good luck wrapping this up, you'll have a good solid motor and peace of mind to redline as you please....
Last edited by RWDlifer; Feb 15, 2017 at 06:30 PM.
BTW how did you clean the gasket mating surface on the engine block so well...
I used red scotch brite 7447 to clean things up, it's has Silicon-oxide in it and just press lightly and it will produce very smooth surface. I just need 1/2 of a pad to clean both surfaces! $0.75 at cost.
Last edited by solarwindp; Feb 15, 2017 at 07:47 PM.
Try to continue during coffee break. ( in my c230~)
After I put the cam cap back on, I was following the Hynes manual to torque down those bolts and I feel weird with the 1st bolt right the way.... it broke!
It's still lucky that I can remove the cam housing and no need to drill the broken fastener .... then I try to figure out why....
It said 15 ft lb but....
It should be 7.6 + 90 deg!
the Haynes provided a figure that as twice as much!
Alright, for playing safe , I placed another order from MB for all 25 bolts for the whole cam housing. Another set of head bolts ordered as well as I don't feel comfortable with a false reading one.
Another $150 and 5 days to wait.
So I redo the head bolts and the cam housing again.
this time the problematic head bolt hole still gave me trouble, still have something wrong when torque, but I managed to do it right this time.
with so many times of pulling and putting back on, I finished the fix within 4 hours from the head bolts.
I also allow a whole day to let the RTV dry then put the engine oil back into it.
2 more things I wanna to mention ..... the last guy who messed up with those balance shafts. The guy thinks just line up all timing marks is good.
In the pic they seems to point to same direction. Actually another one was pointing somewhere else.... that explains why the engine was kinda rough before.
When the crankshaft at TDC, both Bal shaft marks should clockwise 90 degree, point to the 3 o'clock.
As I drained almost all the fluid out of the engine, then I need to refill the next day after things are done. Basically I pour the old engine oil back from the oil extractor. It should be the same 5.5L it needs.
pour it back, it showed 5.5L and I started the engine and everything looks good. No oil in coolant nor water in oil.
Keep it running for 20 mins and then I turned it off. Went home and have a happy meal. Then I check the engine oil again ..... 5.1L ! Oh really!?
Then my wife scolded at me for cleaning up the soaking oil newspaper mess.... She reminds me about the camshafts are hollow and contains quite a bit of oil in them, also the cylinder will contain some oil as well. So I fill it up to 5.5L again and check every single day. Now I am driving for 15 days and it is still no sign of oil loss.
The reason for using the old oil because I am CHEAP! ( I just did the oil change 100 km before the broke down)
Now the engine is way smoother than before and rev more happily than ever. I decided to keep this car for at least a few more years. Next time (+100000km) may not be only timing chain, I may need to rebuild the whole engine.
You're right, that's twice the recommended torque on the cap bolts. I checked my chilton manual (just another haynes, really) and it's wrong too..glad I have WIS
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