tompoeschel

Sorry for never replying to this thread! Not sure why I didn't...

So I ended up buying a 1-owner 2004 E55 from Seattle in early August. It had 99,300 miles on it when I bought it, then I immediately drove it 3,500 miles home to Detroit. It's my daily and now has 113,500 miles. Here's a list of what I've done (all DIY in my garage) so far:

~crank position sensor
~motor mounts
~trans mount
~oil filter housing (plastic cracked)
~spark plugs
~valve cover and breather cover gaskets
~supercharger belt
~heater control valve
~alarm siren (alarm was going off randomly, batteries corroded)
~vacuum lines

And of course, basic maintenance has been done at the required interval. I had an oil analysis done, and it came back excellent. There was no coolant in the oil which was a good sign that the radiator/oil cooler problem hasn't reared its ugly head (most prominent in '03 models). There's still things I would like to do, like brakes, all fluid changes, trans service, supercharger clutch service, new pulleys, etc. But so far, it's been a fantastic car. No major issues to report; I'm glad I went with the M113 motor.

Yuille36

Besides the obvious head bolt issues, the M156 engine really doesn't have any other lingering gremlins.

hachiroku

Devastating issues...no. Maintenance issues yes. The 3 listed items below will need to be serviced anywhere between 100-180k miles. They will need to be done as rubber can only last so long before it shrinks or hardens.

1. oil cooler thermostat o-ring
2. oil cooler hard line's o-ring
3. oil pan reseal

Yuille36

Yes, your correct but this could be said for a lot of cars, as seals tend to dry and get hard as the car ages. This year, I replaced both valve cover gasket and cam adjuster housing gaskets. Last year, I had my PCV valve replaced, that wasn't cheap, as the valve hides under the intake manifold. Replaced the spark plugs, engine coolant, transmission fluid, and rear diff. Replaced all idler pulleys, brake flushed. And now I need to replace my pads and rotors, which I plan on doing myself over the presidents day weekend. Besides the brakes, the only other thing that the cars needs this year is a oil change.

05-E55

Wow, you did motor/trans mounts yourself? In a home garage or are you a tech and have access to a lift?

Strigoi

Plenty of people have done them in their garages on jack stands, it's not a big deal. It's just easier if you have access to a lift.

Yuille36

Although your statement is true, you said it yourself, this only affected a low proportion of M156 engines. However, I'm under the impression that frequently changing of your engine coolant can prevent head bolt separation. As with any coolant swap, you remove the acids and contaminants that effect the head bolt in the first place.

tw2

In theory it should help but nothing changes the female/male bolt design and metallurgy other than changing the bolts. I am fairly confident with no proof whatsoever that you can't rely on this to save the day. Not to mention people are getting these cars very second hand. You already have 100,000 miles on the same coolant in many cases. The corrosion will already be there to some degree in an inherently weak design.

tompoeschel

Yup, it definitely wan't the easiest thing in the world, but I did it. I don't have the exact link, but here's a good DIY thread https://mbworld.org/forums/w211-amg/...ns-mounts.html The easiest way (although it isn't "easy") is to lower the steering rack and jack up the motor a bit from the oil pan. Some guys also remove the exhaust, but I didn't want to do that. The trans mount is very easy and only took about 20 minutes. If you can change your oil, you can do the trans mount.

Yuille36

There is no denying that the bolt design was flawed from the offset. And new head bolts will remedy the possibility of any future failures.

jumph4x

Air suspension aside, which is easily addressable and not that big of a deal, the main thing to watch out for is an oil pickup seal that can and does grenade motors. You're about to start seeing a lot more of this pop up, until soon the E55 platform will develop a reputation for being terrible after 150K (or whatever) miles. Some reasonable guesses and projections would be that cars in very cold climates can expect this terminal failure to happen sooner, especially if driven at HPDE. Basically the temperature deltas between the extreme high and lows. But that's just a semi-educated guess.

SICAMG

That o ring was very "firm" when I pulled my engine out. I only have 70,000 miles too !!
Didn't really care as I had all new seals any how but was interesting to see it that way.

PieRat

Surely it is going to firm up being where it is. Question is and i huess well find out if it turns into a common problem. I think not coz lots of m113s at high mileage with good rep..

hachiroku

any o-rings should be serviced...i had a pretty bad oil leak on my M156 where the engine and oil cooler lines meet. upon removal the thing was hard as a rock and brittle as hell.

jumph4x

Individual in above video bought a replacement motor, tore it open to inspect the same seal and had the same conclusion.

There is no reason to believe it won't happen to all M113K motors, unless you determine that:
- some chemical in certain kind of an oil caused it (extremely unlikely with standardized oil ratings and Viton seals)
- there was a supplier change
- or a part number change.

tw2

Brittle rubber doesn't equal failure. Any rubber seal in any engine after thousands of heat cycles will be hard. That one only failed as a chunk came out of it. There is nowhere near enough cases to draw any conclusions other than it could be a future issue. Most of us also don't use our cars in the same way as the video's author.

jumph4x

YMMV. With optimistic attitude and the right prayer, anything is possible.

tw2

How many actual failures have there been? Just that one? How many engines share this setup, all M112 and M113 engines? I don't know the answers but I am not.convinced it will be a huge issue. If it was easier to get to, yes I would replace it preventatively.

SICAMG

Well my only concern is the fact that these cars where not sold off the showroom floor with that obnoxius oil pump whine.Over time something happens...mostly on a oil change event....who knows.
Could it be that O ring leaking a little??? Would think engine would pop due to pump cavitation but it does sound like a cavitating pump.
My goal when my engine was out was to "find" the cause of this and in the end after a very very close and methodical inspection of pump, gear clearance seals and bearing clearance, that O ring was the only "iffy" part.
Doing work on supercharger so won't know if it's quiet until everything is wrapped up and running.

Jumph4x That guy's engines...both of them looked horrible inside and clearly the oil was never changed when it should have been.
That guy is REAL sharp though and know's his stuff !! A pioneer like yourself.

N_Rob

The engine that blew was also undergoing a lot of stress, more than most probably ever would. He had twin turbo's mounted in the trunk.