W124 E300 Diesel Head Gasket (OM606)

[bobi]

Hi all,

I want to remove cylinder head from engine for various reasons.

There is no workshop manual for this car so I need to know what "special tools" I will require to do the job?

It is the OM606 engine.

Any help appreciated.

regards,
Bobi

 

[roadhog]

I have a German manual and it doesn't mention any special tools. If you like, PM me your e-mail addy and I'll scan the pages for you, they are in German though.

A couple of things to remember, the head is held on with stretch bolts. My book says to measure them and replace them if they're more than 2 mm longer than new. There's two lengths, 102 mm and 115 mm. Personally, I'd get new ones.
The torque setting for the bolts is 15 nm, 35 nm, 90º, cup of tea or 10 min break then another 90º.

If you're taking the head off because of oil in the coolant or vice versa it may be worth checking out your heat exchanger first. They have been known to rot.

H.T.H.

 

[Bolide]

AFAIK you need to remove the cams to get at the head bolts. Be careful when removing the cams as they can snap. You can lock the IP in the correct position with a 4 mm drift or drill bit. Setting the cam & IP timing is key to getting the thing to run afterwards

You'll need small slide hammer to pull a retaining pin, a special socket for the injection pipes out of the IP, a winch to lift the head off, a set of bolts, a gasket set and I'd advise a new timing chain & tensioner plus retipped injectors and new glowplugs. You'll probably need a couple of replacement valves as well. I'd have the head skimmed & valves reground by your local engine machine shop

I did my research, bailed out of the job and got an expert to do it

Nick Froome
www.w124.co.uk

 

[roadhog]

I did my research, bailed out of the job and got an expert to do it

www.w124.co.uk

Hang on, I thought you were the expert?

 

[television]

I can also print off the instructions

 

[Number_Cruncher]

When I did mine, some 30,000 miles ago, I found;

The bolts were in spec, so I re-used them.
I needed to replace;
- the rubber bungs in the crankcase ventilation system
- the plastic clamps for the injector pipes
- I fitted a new upper guide tube for the cam chain
- I fitted new camshaft sprocket bolts
- the injector leak off pipe - you'll need to buy 2 metres, and a bung for No 6.
- The inlet valves on cylinders 5 and 6 needed to have new seats fitted, and I fitted 12 new inlet valves. The exhausts were OK, and were re-used.

The headset I bough contained all the many O ring seals I needed to do the repair, with the excpetion of the injector sealing washers, which MUST be replaced if the injectors are removed.

I found my head to be flat and square, so did not have it skimmed - I don't know how that operation would work with these heads, because the pre-chamber protrudes below the sealing face.

The timing chain guide pins can best be removed with a slide hammer, but, I made a puller tool out of some M6 studding and some tubing.

I replaced all my glow plugs and had my injectors overhauled while the head was out.

Yes, take great care with the camshafts - there's a defined order to be followed in removing and refitting the cam bearing caps to avoid fracture.

The timing chain tensioner needs to be emptied of oil and re-bled prior to fitting. I used a bean tin full of engine oil, and a valve compressor to work it through a few cycles while completely immersed.

The cams can be locked with a drill bit - the tool for locking the injector pump is more involved, and in my opinion unecessary.

You'll need a tri-square socket bit to undo the head bolts (M12 IIRC), and you do not need special tools to undo the injector pipes themselves. However, it is good practice to have 12 plastic caps to hand to cap off the tops of the delivery valves and the injectors as soon as the system is opened. The hard pipes can be cleaned and blown through with clean air prior to re-fitting.

You don't need to worry too much about the chain - I cable tied the chain to the camshaft sprocket, and owing to the tight fitting guide tubes in the lower engine, it did not slip off the crank or IP sprockets.

Unless you're extremely strong, you'll need help lifting the head on and off - it's best to do this very carefully to avoid damaging the sealing face on the head, or the gasket face.

Why are you doing the job?

 

[bobi]

Well thanks for all the quick responses.
Food for thought......................!
I wil u2u those who say they can email instructions.

This goes way back - Some of you may remember that I had oil in water last year & wanted to remove head last year. I took Bolides advice at the time & removed oil cooler which WAS found to be leaking. (Whoopee I thought!)

I could have bought a used one from Mercman for £60 but as most coolers would be approaching pensionable age I thought it best to buy new!!!

£340 pounds later & I had the only one in the country at the time - it was shipped down from Milton Keynes for me.

Anyway, I digress.

All seemed ok. After I renewed the oil cooler & citric flushed the block all was ok for a few months, then temp gauge started to rise again, along with an occasional splurge of oily water found on the front street once every two months?

The water pump telltale was telling tales so I changed it for a pattern QH one (only £50) and again all seemed well for a couple of months?

Recently my water temp gg is behaving very erratic - stays at 83 for days then all of a sudden flits around like a nervous banshee! It never gets abouve 105 deg C & only for seconds at a time but seems to prefer motorways to town driving?
I put it down to either a faulty temp sensor or a dodgy electrical fault behind the dash (God forbid)

The car drives perfectly though, no missing or hissing or anything. Top Rad hose is not solid. New cap was fitted recently.

Today however I walked ouside the front door to find the car had been sick on the road again? Not much, but worryingly enough. No oil in the water expansion tank. No evidence of where the water is from? I'm starting to think that ther is a Leprechaun chucking a small amount on the road just to torment me!!

The temp gg was even more erratic today ( looked more like a windscreen wiper at one stage)

So, i'm fed up!

But then I had a thought................

I am being made redundant in May (and very happy about that as it happens)
I'm lucky that I have offers of jobs comming out of my ears.
My firm will pay me a years wages so I am in no rush.

I thought I may buy a little sports car for the summer (Boxter probably) & play with the Merc head in my own time.

I had a good quote for a OM606 head gasket set & new stretch bolts for about £125 from Ultraparts in Brounton - it is a gasket for a W210 turbo OM606 head but I have been assured that they do fit & are actually better as they are the newer laminated type?? (is this correct)

So now you know the Why - I just need to know the How?

Sorry for the length of post - sometimes its cathartic to just let go & get it all out!

regards,
Bobi

 

[simon_wall69]

Well, all the best; I have considered doing it as mine is rather flat and I think compression has been lost as is normal with these engines but it seems too involved.

But please, please, please, post up some pictures when you do yours so we can all have a look. Will be eternally grateful if you do.

 

[television]

If it is being sick in the road, is it not worth washing down the block to see where the water etc is coming from.

It can only come from the inlet side of the engine, the water pump, or heater hose or pipe and the rad

http://www.detali.ru/cat/oem_mb2.as...GM=717.433&CT=F&cat=44R&SID=50&SGR=165&SGN=02

http://www.detali.ru/cat/oem_mb2.as...GM=717.433&CT=M&cat=19T&SID=20&SGR=015&SGN=01

http://www.detali.ru/cat/oem_mb2.as...GM=717.433&CT=F&cat=44R&SID=83&SGR=180&SGN=04

 

[Bolide]

Wonky gauges can be a bit of a W124 speciality. I wouldn't rely on a gauge that kicks up & down for an accurate temperature reading

I think it unlikely that the CHG is failing. If it were the symptoms would likely be more consistent, water loss would likely be consistent and you'd eventually see proper overheating

I have heard of a 606 with a cracked head. That's the worst-case scenario. If you take the head off do have it skimmed & pressure tested

I would personally use the "correct" gasket and buy it from a dealer. It prevents that awful sinking feeling when the engines done & all buttoned up and something goes amiss

Nick Froome
www.w124.co.uk

 

[Number_Cruncher]

>>Wonky gauges can be a bit of a W124 speciality.

Especially as the wiring in that part of the engine near to the coolant temperature sensor on OM606 equipped W124s is the most likely to be degraded by heat. I replaced the engine wiring harness on mine because of the insulation damage I found while the head was off.

 

[bobi]

Thanks for all the replies.

I note the dodgy wiring issues & will probably go down that route before ripping the head to bits.

regards,
Bobi

 

[television]

I am printing off now, quite a few pages

 

[television]

You say 606 engine should that not be the 603 engine for the 300d

 

[bobi]

No, definately 24 valve 606 normally aspirated engine.

It is a late 93 saloon E300 (with a spoiler woo hoo!)

bob

 

[television]

OK a 124191 in the morning now

 

[bobi]

television (Malcolm)
Changing the subject slightly & noting in your sig that you own a SL500
What would the servicing pricing be (money wise) for a 2002 S500? (roughly)

How much could I do at home & how much would be specialist?
regards,
bobi

 

[television]

It all depends on how brave you are.

The ABC can give leaks, I have done my own, to get air out of the system you need to have all 4 wheels hanging.

The electrics are complicated but studying the diagrams, it can all be worked out.

You can change all of the brake parts even with SBC.

The engines are just standard 119's

Much of any repairs involve much dismantling of panels etc.

Servicing cost are just the same as for any other car, with the exception on changing the brake fluid, that must be done on STAR.

Roof leaks you can fix yourself, but some not cheap if you have to replace rubbers. Mine are all fine and I have done all of the mods

 

[bobi]

ta.
food for thought as there is one for sale near me and it seems a lot of car for under £5000, even with 150000 on the clock

 

[Goodolboy]

W124 e300d clank noise when cold

Hi there , i have just joined the forum today , a few weeks ago i purchased a W124 e300d OM 606 engine , i took a gamble on the clank noise it was making when cold and thought straight away the water pump bearing had gone , i changed the pump yesterday , even though somewhat a little less noise , i still have the clank at the top of the engine , when revs go up above 1500 RPM it goes away and the engine is sweet sounding beast , also when it gets warm it also goes away , i have to change the small damper at the front as well as that is metal to metal and buzzes , but couldn’t get one yesterday in time , i have sorted that for now with a piece of rubber , so it's got to be something else ....could it be the chain tensioner ???? , would really appreciate some help here ,, many thanks Andy