dumbest ever reason for head gasket replacement
 

Well, for reasons I'd like to not elaborate on (my stupidity), I have need to replace a prechamber on my OM603. I successfully removed one on my junk engine, but the one with damaged threads in the current vehicle would not come out and is irreversibly damaged after the attempt.

I need guidance in removing/reinstalling the head, but please bear with me as I go over some background.

First off this is the OM603.971, rod bender, of w140 fame. The engine is using a quart of oil every 1500 miles. Previous owner had run this junkard engine for at least 30,000, but no telling the original mileage.

I'd like to remove the cylinder head in order that that the local Dayton Genuine Auto Parts machine shop might replace the damaged prechamber (part acquired from Metric Motors). Planning to have them do valve seals, etc. (questions to come on that.)

I've got a friend who has done head work on a couple diesel engines (not Mercedes) who is willing to assist if I get stuck in the process. He is not one to skimp and has advised lifters, intake valves, exhaust valves, seals etc. for the head. 12 lifters at $20 a pop is not making my day, but I've seen postings by respected members such as GXSR indicating these do go out of spec. All of this would be done by the machine shop.

The immediate questions pertain to how far to go with valve seals,etc. I want to do an initial part order soon. Here is the potential shopping list:
1. Hylomar sealant – thinking the racing acetone based may not be the best choice, but this is quite confusing, seams like the original only comes from England.
2. Elring head gasket kit – This is OEM. the machine shop says if they plane head some a thicker gasket is needed. I am not seeing that as an option for OM603.971.
3. Canyon Valve guides for both intake and exhaust (1st oversize) – does not say OEM ($5.50 versus $13.50 for Mercedes part on Pelican)
4. Intake and Exhaust valves – Intervalves brand way cheaper than Mercedes part for exhaust valve ($14 versus $58 on Pelican)
5. Valve Cover Gasket – DPH or CRP both 1/3rd the price of merc part on Pelican
6. Cylinder head bolts – about $40 for VictorReinz OEM
7. Cylinder head bolt tool-- need recommendation as Pelican is out. It would be great to find East of Missisippi dealer for fast ship to Ohio. Probably going to call local place here called the Tool Crib so I can get this fast (may cost me $75 that way).
8. Valve Stem Seal set – Elring and CRP at Pelican are $10 or so, merc part $50. My old standby ******** just carries the Elring.
9. Exhaust Seal Ring (Mercedes) from Pelican – looks like one of these going from exhaust manifold to rest of exhaust system (pretty sure manifod will need to come out?)9.
10. Valve Lifters – Ina is supposed to be OEM at $15 a pop which is better than $40.
11. Star Classic W140 repair manual – never seen good info (alldata not great) for the w140. Site is offering the DVD image for $20....Does this sound legit. I heard its not the easiest to use too. (I've gathered some info on tightening and loosening order for head, but don't have any torque specs for any of the related parts...)
12. I don't think kit comes with turbo metal gasket to manifold, the OEM VictorReinz gasket to the drain pipe, or the OEM Elhorn intake airhorn gasket.
13. Valve Springs – well their under valve springs at Pelican and called Valve Keepers. (looks like half a cylinderical shape)
14. Professionally rebuilt injects are ready for installation.

I've concatenated many posts, but this post is dragging on too long for inclusion here.

Stage 1. Tools and directions on how to take apart head
Stage 2. Acquiring parts for valve/head recondition
Stage 3. Pick up parts for reinstalling head

I really need help on stage 1 and 2. Any guidance would be greatly appreciated.

My cautious side (mixed with some cheapskate) says the head does not leak, so remove it and tap the damaged prechamber out with wood dowel and mallet while supporting head (but this could warp head.) If done right, nothing is disturbed and I won't feel like I broke the engine.

This is a huge job so another side says to put in a lot of new parts and have pros do this. More expensive. Downside is if the engine doesn't last or run right with new parts I'll feel like I broke the engine. Less might be more with a long lasting rod bender.

Planning to take a look at pistons and clearances to see if this engine is well on the journey to rod bender status.

The car is in great shape otherwise as I have pillaged many things from the defunct Bambi mobile. Previous owner go hit by the evaporator and many other things. Think I have door lock and bumper work left and it would be darn near perfect.

You may not have to purchase all of these parts. I would expect plenty of them to still be good. A simple valve job and a skim of the head surface should still have you close or within new factory specs..

If the head is machined, shims may be needed for the prechambers. When lifting the cam off the head the forward thrust washer can drop off into the chain area. Vac. pump should be removed. Quality ball end long allen wrench 3/8 drive bit is helpfull in getting the intake manifold off. MB manual recommends having the rad cap off until operating temp is reached.

The job is easlier than it seems.

1. NAPA should have it.
2. I have used Elring and MB headgaskets with success.
4. Doubt if valves will need replacement.
5. Have used new victor reinz and re-used orginals, after measuring.
7. Snap on head bolt bit works excellent.
8. Recommend MB seals.
10 .Only if needed.
11 .Best advise for the job is on this site.

Thanks for reply
 

Thanks for the great reply. I'll probably get a set of OEM Ina lifters and return them if not needed. Machine shop seemed keen to handle any issues with valves. I'll cough up for Merc valve seal set per your recommendation.

Not a snap-on, but this looks like the right tool for the cylinder bolts and $40 for delivery in 2 days from NY:
Assenmacher Specialty Tools 12 Pt Cylinder Head Bolt Socket - Toyota, VW, Audi, Mercedes 10mm
140mm Long.
Used for Removal and Replacement of cylinder head bolts.
Applicable to OM 601, OM 602, and OM 603

Snap-on catalog gives me a headache.

I finally bumped into directions from site (courtesy gsxr):
http://www.w124performance.com/service/w124CD1/Program/Engine/602_603/01-5800hx.pdf

Looks like with this tool one can avoid removing the camshaft and camshaft towers (Parroting this). The bolt sequence is impossible to see in the pdf. Attached legible image.

If you could find a really good 3 litre 603 engine cheap enough in a rusted out car or damaged one. It may be a better overall course.

If you are already using a quart every 1500 miles with no oil leaks it may indicate problems ahead.

Don't beat yourself up about pre-chambers they are some of the biggest known buggers in the universe.

In my experience it is always better the devil you know - I wouldn't try and find a good replacement engine part - I'd be rebuilding what I have - or alternatively rebuilding a replacement. But that's my choice.

Whatever you do I'd not fall into the trap of thinking "oh I'll order everything" and then the job will go more quickly. You'll just be disappointed. Take your time - take it to bits - clean measure and check. Then make a list. Then go shopping.

Mankind seems to struggle with the good job - cheap job - on time job vicious triangle <= don't get sucked into wanting all three things at once!

Putting serious money into a 3.5 litre so called rodbender engine. This to me is questionable. Especially if there are indications of already existing oil consumption at a quart every 1500 miles.

If a person should want to go ahead at least wait till the head is removed and cylinder bores and piston heights examined before spending any money on parts at all.

There is no loss in doing that anyways because if the block is questionable by examination. You would want to save the high number head in my opinion. If possible and practical put it on a 3 litre block in fact if there is only a number fourteen head on a sourced engine. Or save it just in case the the head on the replacement 3 litre cracks.

Another thing is in all probability there is a better chance in locating a good used 3 liter 603 engine now than say in a couple of years.

The old expression of do it once and do it right comes to mind. Especially if otherwise the car is in good e shape. Stretch in the previous post is located in Europe. Where apparently the 3.5 does not develop the same problems. Or if so almost on a neglishable scale in comparison to the ones exported to north America do. One school of thought is the better diesel fuel over there may make this difference. My own feeling is that the engine is just inherently weak structurally in the block and perhaps some reciprocating parts compared to the 3 litre 603 engine..

Plan Z
 

I leaved on pins and needles with my previous rod bender. It consumed a quart of oil every 500-600 miles. Bought it with a 150,000 miles and it made it to almost 300,000 before Bambi took it out. (I'm due $7000 from insurance, but I am keeping the car around for practice til the new one is done.) Once these w140s make it to a certain point they are supposed to last a while. I've got good feelings on the black one.

Plan Z when I bought this car was to put in the OM606 engine from 98/99 E-class, ala JTripp. If I had a blown head gasket and were going to a shop for this process, I'd probably make the leap. Sixto has recommended the 3.0L engine as a replacement. The current job is a big step up. Perhaps with that under my belt I might be crazy enough to attempt an engine swap.

My hope is that the head will check out and just need the new set of Merc valve seals. I don't care what the cylinders look like, but I'll report on them and attempt photos.

Ordering up everything today. I am sure I will be too slow on this project, but I'd rather get it back together quickly while everything is fresh in my mind.

I'm really confused.... you seem like a person that really is interested in doing things right and having a car that is running 100% to spec, I'm the same way.

But help me out here a bit, your willing to spend several thousand dollars on new valves, injectors, lifters, machine shop work, labor, documentation to make sure your doing everything 'by the book' but you're then willing to bolt up your now perfect cylinder head to an engine block that, more likely than not, has cylinder bores that are 4-6X out-of-spec for taper?

The OM606 swap, especially with a turbo, would be the way to proceed IMHO. A W140 with a OM606 turbo would be one sweet ride and I could see making a long-term commitment of time and $$$ to make that one happen as being worth it. Best of luck with which ever way you go.

[QUOTE=Meles;3152776]Well, for reasons I'd like to not elaborate on (my stupidity), I have need to replace a prechamber on my OM603. I successfully removed one on my junk engine, but the one with damaged threads in the current vehicle would not come out and is irreversibly damaged after the attempt.
QUOTE]

I might be able to figure out a cheap way to get the Prechamber out if I knew more details as to what happend to the Prechamber and what Tools you were using to try to pull it out.
Also I am not sure if it is only the Prechamber itself damaged or the Head?

If only the Internal threads of the Prechamber that the normal Prechamber Puller Tool uses are stripped I have Taps that size. M22-1.5

I also have My own type of Prechamber Puller that is different from the standard one; I believe it has a longer threaded area. Meaning it might be possible to go inside and take the Tap and thread down further inside the Prechamber and install the Puller and yank it out.

Another way might be to do the above using JB Weld before the Puller is screwd into place; let that Epoxy cure and attempt to yank it out.

Could you post a pic of the buggered part?

I would suggest selling me the 603IP and swapping in a junkyard motor, or a 606.

Have you consulted a machine shop? They may be able to coax the prechamber out.

[QUOTE=Diesel911;3153218]This is a great suggestion. My puller's threads are trashed from trying to get the injector out. I don't see any harm in trying this.

Another poster liked OM606 idea. It doesn't quite slap in and I don't have a hoist, etc. The cylinder task is daunting enough, though the price is rising. Heading towards a thousand dollars plus a lot of work all from my boneheaded mistake.

loneranger is having problems getting out PC chambers on his rodbender too. You might have to have a machine shop EDM it out, as disimilar metals can be really bonded together. Damn aluminum!
The 606 would be a immense pleasure I assure you. A member sold one in SoCal for around $2000 last month. The extra electronics involved need to be solved but I think thats doable and you need an intercooler to make it work properly. The 4V engine has incredible fuel economy if you don't push it, but when you do push it the torque is huge and you will smile big time :)


[QUOTE=Meles;3153321]

If you do a complete cylinder head rebuild, you will be rewarded with:

An engine that uses 1 qt every 500 miles.

An engine that may bend rods due to new found power.

Really, having good valve sealing on worn rings will draw lots of oil into the combustion chamber. Not only will oil consumption increase, compression ratio does too.

Your friend that has worked on some diesel heads, is he a mechanic or someone that has done some at home repairs? If mechanic, is he heavy equipment or light truck?

Him not "skimping" and wanting to throw every part at the head could be considered not knowing what parts are worn but are reusable Vs what parts are too worn to continue. Another consideration is that heavy equipment engines need to run at full power for extended periods so they need better parts what would survive in a lightly loaded automotive app.

There is always a risk in patching up a worn engine and something will always be left undone. If you do all those "just one more things", you end up with a rebuilt engine.

So, if this engine was running and driving, would you have removed the head for a total rebuild? If not, pull the head, change the prechamber, look the head over for obviously burnt valves and reinstall. ( exhaust valves will always leak a slight bit on a worn motor )

The next step, if the car is worth while, have a spare engine waiting ready to go. A 606 swap is probably beyond your level due to mods needed, but a 3.0 603 is supposed to be a drop in, others can speak to the specifics.

[QUOTE=dieseldiehard;3153337]loneranger is having problems getting out PC chambers on his rodbender too. You might have to have a machine shop EDM it out, as disimilar metals can be really bonded together. Damn aluminum!
The 606 would be a immense pleasure I assure you. A member sold one in SoCal for around $2000 last month. The extra electronics involved need to be solved but I think thats doable and you need an intercooler to make it work properly. The 4V engine has incredible fuel economy if you don't push it, but when you do push it the torque is huge and you will smile big time :)


Longranger sounds like He is having trouble getting the Prechamber Retaining Ring off; but I am not sure and ask about that.

[QUOTE=Meles;3153321]I am finding this confusing as the Injector should have already been removed before the Prechamber Retaining Ring and the Prechamber can be removed.

Also were you useing a Real Prechamber Pulling Tool or similar to in the Picture. The 22-1 threads is for the Prechambers that have a Slotted Retaining Ring the 22-1.5 is for the Prechamber (angle Injection) that uses the Serrated Prechamber Retianing Ring and the Injector Screws directly into the top of the Prechamber.

I also think it takes a Slide Hammer like is in the Pic to do a decent job pulling the Prechambers.