DIY: Head bolt swap on M156.
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From: Kitchener, ON
2010 C63 AMG
If you already have coolant passing the head gasket then you either have a broken or stretched bolt. Most likely stretched. Thing with that is, you go to remove that stretched bolt and the head busts off when removing it and your screwed. Now you have to pull the engine to get the head off and remove that broken bolt.
If you get lucky and the bolts all come out but coolant has already passed through the gasket, you might be ok if you torque down the studs, you might not...
If you get lucky and the bolts all come out but coolant has already passed through the gasket, you might be ok if you torque down the studs, you might not...
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Joined: Aug 2011
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From: Kitchener, ON
2010 C63 AMG
You make it sound impossible. It's not that deep in the head casting.
Of all the old bolts I've seen on here the threads look clean. How much resistance was there once the bolt was cracked loose? Could you turn it by hand easily?
Of all the old bolts I've seen on here the threads look clean. How much resistance was there once the bolt was cracked loose? Could you turn it by hand easily?
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From: Silicon Valley, CA
C63 AMG, P30
So in this video, where exactly do we have to stop pulling bits off of the engine to replace the studs? About the 3:15 minute mark?
I'm assuming after you've taken apart the head, you can replace the bolts one at a time.
Sorry for the newb questions. I'm a fairly competent DIY'er, but haven't been in the AMG scene for a couple of years now.
I'm assuming after you've taken apart the head, you can replace the bolts one at a time.
Sorry for the newb questions. I'm a fairly competent DIY'er, but haven't been in the AMG scene for a couple of years now.
Last edited by AMG3.2; Nov 8, 2015 at 10:29 PM.
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From: Silicon Valley, CA
C63 AMG, P30
Thread Starter
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C63 AMG
Yea the dealer should be able to pull the service history. We had one guy here, we were gonna do head bolts and my friend checked at dealer, it was already done, he never even knew.
Junior Member
Joined: Oct 2011
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From: SF Bay Area
2011 C63 AMG P31
I have not done it yet, but I'm going to soon: Weistec studs SLS buckets and maybe their billet idler set. Cam timing kits are available on line and have all the necessary tools. The Weistec instructions are excellent and you can download them to study up a bit. The buckets can be easily removed with a magnetic retrieval tool which is how I do it on my motorcycle.
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Joined: May 2011
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From: Fort Worth TX
2020 S560, 2014 SLK55 (Prev. 2016 S65, 2013 SLK350, 2008 CLS63, 2006 E350, 2006 CLS500, 2005 C230K)
Bolts one by one
I'm thinking of doing the one by one bolt swap.
Did this work for you or did you ended up having to do the full gasket R&R due to compromised HG?
Did you follow any specific replacement pattern / tightening procedure?
Did this work for you or did you ended up having to do the full gasket R&R due to compromised HG?
Did you follow any specific replacement pattern / tightening procedure?
Member
Joined: Aug 2013
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From: Reno, NV
2012 ML63 AMG, 2015 RAM 2500, 1968 Charger
I'll jump in here an say that if you've had the check coolant level light come on at all, you're in for a head gasket R&R. I speak from experience, unlike those that tried to tell me to just do the gaskets, once these gaskets have started to leak, there's no way to get them re-sealed without removing the heads. When I was researching MLS gaskets before my experiment, I had read several accounts of people re-using them, but they always did some sort of surface prep to the gaskets before re-using them (ie. coating them with copper spray gasket) and had no issues, whatsoever. However, take my word for it, if you're already using coolant, you need to replace the head gaskets. I've got about 5k on my new gaskets and haven't used so much as a drop of coolant. I didn't get through 2 tanks of petrol after changing just the bolts and was already using coolant. Just my $.02. Best of luck.
Super Member
Joined: May 2011
Posts: 972
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From: Fort Worth TX
2020 S560, 2014 SLK55 (Prev. 2016 S65, 2013 SLK350, 2008 CLS63, 2006 E350, 2006 CLS500, 2005 C230K)
Thanks, appreciate the feedback.
I don't have a leak (yet?) but was thinking a bolt swap is something I'd do for preventive maintenance; a HG is maybe too painful for preventive.
On another note (maybe for future reference) did you use the official puller for the drive gear? I assume the gear does not fit into the engine, as in it won't fall into the crankcase?
I don't have a leak (yet?) but was thinking a bolt swap is something I'd do for preventive maintenance; a HG is maybe too painful for preventive.
On another note (maybe for future reference) did you use the official puller for the drive gear? I assume the gear does not fit into the engine, as in it won't fall into the crankcase?
I'll jump in here an say that if you've had the check coolant level light come on at all, you're in for a head gasket R&R. I speak from experience, unlike those that tried to tell me to just do the gaskets, once these gaskets have started to leak, there's no way to get them re-sealed without removing the heads. When I was researching MLS gaskets before my experiment, I had read several accounts of people re-using them, but they always did some sort of surface prep to the gaskets before re-using them (ie. coating them with copper spray gasket) and had no issues, whatsoever. However, take my word for it, if you're already using coolant, you need to replace the head gaskets. I've got about 5k on my new gaskets and haven't used so much as a drop of coolant. I didn't get through 2 tanks of petrol after changing just the bolts and was already using coolant. Just my $.02. Best of luck.
Newbie
Joined: Mar 2016
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2009 mercedes c63 AMG
hey in this first picture can you see if there is a way to get to the timing cover bolts with out taking the camshafts out? I am looking into replacing the timing cover on mine 09 c63 and just wondering what all i need to take off. if you can shed some light it would be greatly appreciated!
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Joined: Aug 2011
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From: Kitchener, ON
2010 C63 AMG
hey in this first picture can you see if there is a way to get to the timing cover bolts with out taking the camshafts out? I am looking into replacing the timing cover on mine 09 c63 and just wondering what all i need to take off. if you can shed some light it would be greatly appreciated!
If it's the bolts from the cam adjuster cover, (#225) you don't need to touch the cams to replace that.
Newbie
Joined: Mar 2016
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2009 mercedes c63 AMG
no those are not it. on the top of the timing cover there is two bolts on each side.If i can figure out how i will try to submit a picture to show you what i am talking about
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From: Eufaula, Al/Georgetown, GA
W213 E63S Wagon, W204 C63 P30(RIP), WK1 Grand Cherokee SRT8(RIP)
Newbie
Joined: Mar 2016
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2009 mercedes c63 AMG
oh ok. so the timing chain will have to be re set once i take the cover off? i got an alldata subscription but it doesnt give me a whole lot of info on the removal procedure.
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Joined: Aug 2011
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From: Kitchener, ON
2010 C63 AMG
Below pics from George's build.
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Joined: Nov 2013
Posts: 825
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From: Eufaula, Al/Georgetown, GA
W213 E63S Wagon, W204 C63 P30(RIP), WK1 Grand Cherokee SRT8(RIP)
Great post Jason and I believe I will stand corrected...if you look at the center of the center unit you see that snout on the front? That is what is integral to the timing cover but those pics definitely show it still in place with cover gone....what I was going by was the procedure for head removal which included removing the front cover and showed removing the gears with a special puller tool prior to cover removal.....good man!
