Enigma94

Hey guys,

Well the motor on my ML63(135K miles) has the dreaded valve tappet issue arise and its looking like its going to be 6K to fix if the cams are still in good condition and close to 10 if i have to replace the cams.... So im looking at getting a used motor and just doing a full swap out for something with less miles and hopefully a 09 so I dont have to deal with the tappet issue again down the road. I was wondering if anybody knew if the M156 from the E63 and C63 would be direct swaps? I cant seem to find any used motors specifically from a ML63 online.

TIA!

zenman63

You can fit the late engine with the black plastic covers, but there are parts that you will need from your ML63 and as follows.
Sump inc lower section of engine.
Oil pump, parts will swap over as its just the pickup thats different.
Flywheel
Engine mounts
Manifolds.

Enigma94

What exactly do you mean by "Sump inc lower section of engine"?

oil pump might suck to swap, but everything else seems to be relatively easy/straight forward.

I'll be having a shop perform the work as I just don't have the time to do it myself so i'm trying to gauge a cost outside their quoted hours of labor for a straight swap to see if its worth going with a newer motor from a E63/C63.

Whiplash_89

Can you ELI5 on this tappet issue? i see tons of pages regarding it but its all a little overwhelming. Has the 09+ ML63 engine fixed this issue or is it still a problem?

Thanks.

905legend

I've done the swap used a c63 engine. The lower rad hose housing needs to be tapped and swapped over. You need to swap over the ml oil pump and oil pan. The flywheel and exhaust manifolds and engine mounts as mentioned.

Enigma94

There was a a issue with the valve tappets in the earlier M156 motors where they had made the tappets out of metal material that would end up grinding into the cam lobes and destroying it after a while. They issued a TSB for the issue and switched to a new type of material for the tappets in 09. I had my tappets replaced on my 08 E63 (55k miles)through the dealer and factory warranty to the new ones. it was roughly $5500 in work because I caught it before the cams were damaged. If you have to replace the cams you'll be looking at 3-4K more through a dealer.

How to tell if you have a tappet issue is there will be a pretty pronounced clicking noise at start up, and it will continue even after the motor is warmed up.

What about the above mentioned "Sump inc lower section of engine"? If I have to swap over the whole oil sump system that sounds like a nightmare...

Also, could you elaborate a little on the lower radiator housing swap??

Thanks!

zenman63

Sump is easy so is the oil pump with the engine out on a stand, spin it upside down and remove the bolts, take the top chain guide off the oil pump and it comes out.
Remember all the bolts have to be replace on the flywheel.
You will need the case sealant from MB and the cleaner.