M120 V12 Cylinder Head Removal

[@tunnelportterror]

My '94 coupe s600 has a completely different oil pan on it. The lower pan on mine is located in the back. And those extra bolts on each side are visible from the bottom of the engine.

[@markscars1069]

Owned a C140 600 several years ago and had to sell it to pay for a house. Now we have a plan to find and buy another and keep it, with the intention of working on it myself, so these videos are an incredibly helpful library of content. Massive thanks to you for this.

[@FriendlyMBTech]

You're very welcome!

[@keithexum7312]

I have worked on these 120’s love the M119 and 120. Had to replace and install all new wiring harnesses. Biodegradable insulation nightmare. I was glad it didn’t smoke the Egas computers.

[@tunnelportterror]

Another sign this engine had timing chain / guide rails / tensioner problem, the tensioner was fully extended Beyond its limit of travel of mechanical detent grooves inside tensioner, for the small snap ring to lock into. The minimum length at the first detent about .100" extended, the last detent groove is .625". Beyond that the Piston goes into free bore at extreme end of travel, meaning the timing chain and/or guide rails were shot. That engine had timing chain noise, and was taken out of service.

[@LynxStarAuto]

The way I have always done cylinder head bolts is you start at #1 on the disassembly, and start on #1 on the reassembly. You never work backwards through the number sequences. The idea is to remove the stress from the middle of the head outwards. That was the way I was taught, from my dad, tech school, and throughout my time at the dealers. 🤷‍♂️

[@FriendlyMBTech]

I did it this way because I was following the work instructions step by step. That's how MB says to do it so that's how I did it.

[@bernardgelderblom8818]

Great informative video . Keep them coming !!

[@narcissistinjurygiver2932]

how much do the head gaskets cost nowadays?

[@FriendlyMBTech]

Part only or parts and labor?

[@narcissistinjurygiver2932]

@@FriendlyMBTech they have to green f cover seals at partsgeek for under 7usd.. how much cost for head gaskets. not labor

[@FriendlyMBTech]

@@narcissistinjurygiver2932 about $115 per.

[@fm8453]

Many thanks for these informative videos. I am planning to use an M120 in a Superlite SLC build. First a a ~stock one to get the first revision of the car done, registered and street legal. Then upgraded engine internals with the goal of around a 9000 rpm redline. A question on the stock VVT system though: how does it work; the cams only seem to have one condiguration.

[@FriendlyMBTech]

Only the intake camshafts are variable. They're controlled by actuators on the front cylinder head covers.

[@fm8453]

Yes, but usually one can see two distinct profiles on each cam lobe (for two different settings). Is the VVT a seamless system, where the cam profile is different over the extent of a lobe, longitudinally?

[@FriendlyMBTech]

@@fm8453 it only has variable timing. Not lift.

[@JMSpeedshop]

Your testing the hydraulic lifters. And the are not solid. But if you take an engine that has run recently. The lifters should be solid. If the are springy. Like you mentioned that are leaking internally. But maybe i did not understand your explination correct 😉

[@FriendlyMBTech]

The lifters should be solid with oil pressure. This engine hasn't run any kind of recently. On the M119, there were lifters that were seized and solid with no oil pressure. You could see the plunger stuck in the compressed position. With no oil pressure, the plunger should compress freely and smoothly.

[@JMSpeedshop]

@@FriendlyMBTech after a long time maybe. But there is a check valve in them that should keep the oil inside. If have done a video on the hydraulic lifters on m113. How the work in a m113 and m112. The design is different . But though these should also have a check valve otherwise on every cold start you would here al the lifters ticking

[@FriendlyMBTech]

@JMSpeedshop yes, they should have a check valve from preventing the oil from draining out, but the oil inlet is just a hole. You can squeeze the plunger, and oil will come out. These lifters have been out of the engine for a while and in various positions since being removed so not much comes out.

[@JMSpeedshop]

@@FriendlyMBTech oke that makes sense then 👍

[@MMWA-DAVE]

How annoying is it - that MB just discontinues random small but crucial parts of an engine. Not the first time and certainly not the last.

[@FriendlyMBTech]

💯 The seal for the timing guide between the heads is no longer available also. And it's not like it's an o-ring either. It's an insanely specific seal.

[@narcissistinjurygiver2932]

@@FriendlyMBTech let me know if you find these parts.

[@MMWA-DAVE]

@@FriendlyMBTech 🙄 btw, i recall in the past seeing some M120’s had engine oil to coolant heat exchangers between the V’s. Does the US version have an oil to air cooler externally?

[@narcissistinjurygiver2932]

yea, try getting transponder keys for 90's mercedes.

[@FriendlyMBTech]

I believe they did. There are two oil lines coming off the bottom of the oil filter housing.

[@BANGBANG-zb7eo]

hi i'm having fun from japan The green monster (gasket) that was trying to make me go bald the other day was a little dizzy at the beginning I'm sorry if it's weird English with google translate

[@FriendlyMBTech]

Yes, some of the gaskets can be very stuck making removal of parts more difficult.

[@hansrudigermaier1471]

👍✅

[@ccarlock8537]

Bad idea for magnetic anything on bucket, its fucked now and bye bye cam sooner then later

[@FriendlyMBTech]

The M119 I rebuilt the same way is still going strong 15k miles later. I drive it every day and it runs smoother and quieter than anything Mercedes-Benz puts out in 2023.