Rebuilt OM603: Head Gasket Failure.
 

I rebuilt an om603 about two years ago. New liners, everything. #20 head. Had the head milled and blocked decked when they did the liners. I used a victor reinz organic gasket. Thing ran great for two years, i mean really good. I was gonna build it up and make power but I decided it was good enough (coming from 617) and I just appreciated the potential reliability. Past few months Ive been using coolant and thought it was my rad, or something in the engine bay. I could smell the coolant when I would walk in front of the vehicle so I just kept adding coolant and planned to do a bunch of heater hoses and stuff soon anyway. It then started activating my coolant light every other time I drove. I found a small bit of pressure in the system in the morning and just got pissed. Sure enough last weekend the car was just running a bit warm but it was a cool day. On the way back home I held 85 up a few hill climbs into the foothills, never hitting full throttle but noticed temp rising quick and realized it really is a bad hg. Got home and it idled like ****. Could not restart then puked water out tailpipe and ran ok. so i let it burn the steam off, relieved it of pressure and drained block. Got the head off and #1 had a clear breach into a coolant passage. The fire rings on 1 and 2 looked like soot had creeped under them. I don't know what I did wrong! New bolts, planed surfaces no overheats and a #20 head. Maybe its the victor reinze gasket. Maybe the compression ratio got two high?

So I ordered a MLS om606 gasket from the dealer, 2nd repair size. I got it ($205) and Im pretty worried about a few things. I have to drill about 6 holes for coolant and don't know best way to do it. I borrowed a hole punch set (type you hammer in) but I'm not sure this is going to do the trick. I plan to start a small hole and put a conical burr into it to enlarge it. Theres also an oil passage im worried about at the front of the head. Im also really worried by the fact that the rubberized sealing compound is worn off the gasket from the cardboard packaging. $200 gasket and they cant zip tie it in place or some ****.

I was reading on STD about this but theres not much. its all conflicting info. Some say it works just drill holes and others say the expansion slots between cylinders on the 603 will always leak. One guy posted a head picture but he must have a later head without the milled in oil passage mine has. It just doesn't look like the 606's gasket, with its crimped areas, is going to seal this timing chain tensioner oil passage to the outside of the block. I also read one guy saying even the 606 repair size is thinner than the original 603 gasket. I bought the 1.81mm

I need the sd back on the road asap to commute to work. Im thinking Ill drill the holes and see what happens. it'll probably fail soon but maybe we''ll all learn something and its a pretty easy head to remove. Anyone done this?

I have the head torque down with the 606 gasket. Ill put manifolds on and report back tomorrow. Im worriedat the least its going to leak oil from the timing chain tensioner oil gallery. I ended up dissassembling the gasket to deburr it after drilling it and decided to coat all layers because I don't really think this is gonna work. Especially with the messed up coating and me messing things up even more. It'll probably be off again next weekend and Ill use a dealer 603 gasket (trying to get an erling instead of reinz) that time if this doesn't seal.

From what I've read 606 MLS gaskets in a 603 will have a very short life because the block has some different openings in it that don't work with MLS

Well I got it on and running. its working so far. I drove, and wasn't nice to it. I want to know now, not in a week. Anyway Its sealing so far without pressurizing the system. I am worried about the expansion slots causing failure but I'll keep this thread updated if it fails so we can all know for sure. So far no external leaks either. Ill probably be nice to it for a while now that its working until I can buy a 190E (want to turbo an m103 with a manual trans, make an bmw killer). After buying the 200 dollar gasket I figured I had to try and we can all learn. I researched and couldn't find a solid answer so I'll find out myself and post it.


If/when this HG fails Ill try to source a erling organic gasket from the dealership and install dry.

Did you use a 603 gasket originally?

Was the gasket thick enough to compensate for black / head milling? ( did everything get measured? )

Why are you using a 606 gasket?

I ended up getting the victor reinz gasket. It was the only one I could order, Did not try dealer. I was inspecting the gasket again today and noticed the #1 cylinder breached in several spots, and #2 fire ring was beat up as well but all others maintained a seal it looks like. I really wonder why the two front cylinders failed to seal (well,i drove 50k after the rebuild and really beat on it, I enjoy my cars so I guess it sealed OK). Im using the thickest om606 gasket from the dealer and its working so far. If this fails im going to try getting an erling OEM composite gasket from dealer and OEM bolts however Im starting to doubt they even still have the gasket available. They only had 4 606 gaskets left in world (in their system) and couldn't get the other sizes, and that's for a 99'. Im just going to keep trying gaskets and methods. I did not check flatness because Ive never had it hot and its got 28 head bolts to compress it. Would have still ran it anyway if it was warped. I just needed this car back together. Im getting tired of this rare motor problems stuff. Kind of want an m103 201 for short range and the diesel for important tasks.

I installed a #17 head on my '87 wagon, did not have the head touched other than new valve stem seals and a check for flat. I used the MB dealer gasket, new head bolts, and I chased the block threads with a tap and cleaned them out really well. Fresh engine oil on each head bolt as it was installed, followed the factory service manual torque procedure EXACTLY. Within a few months of the head installation, I towed a couple thousand pounds of wood flooring up and down the NC and SC mountains in July, the engine temperature gauge stayed in the 110 to 115 deg C range the entire all-day trip. that was over 20k miles ago, no issues at all with the head or coolant loss.

MB gaskets are more than plentiful for 603's. the biggest waste of time is a victor reinz anything.

they're $124 for the kit from MB, I build 7 603's in the past 2 months so they're burned into my memory.

Who makes the MB gaskets? Auto makers generally don't make this kind of thing.

elring.

my response was geared towards the lack of availability in 606 gaskets from MB, per OP. not sure why they had a difficult time sourcing anything other than VR for gaskets..... i'd hope VR wasn't used on the rest of the motor, that'll be leaker in no time.

So far (500 miles) and no issues yet with the MLS. No pressure in the morning.

Funny, when I installed my head, at first I did get some pressurizing overnight, but after getting the engine really nice and hot, all that sealed up and became normal. I think a did a few Italian tune-ups shortly after installation, got the temp up over 100 deg. C.