Attempting to fix 190e head gasket

[jonn]

Hello,

I am attempting to fix my Mercedes 190e head gasket and have been following a Haynes manual and so far so good until now!

It says disconnect the exhaust from the engine block but the 2 bolts that hold it on are set hard and will not budge.

I have tried wd 40 and nothing..

It is so hard to get at from underneath (using ramps) and i am having to use an extension on my socket set but there is not much room to move.

Does anyone know if this is an absolutely essential part or if there is another way around at all?

 

[grober]

Do you mean the 2 bolts/studs on the clamp that holds the exhaust downpipe to the manifold? Best got at with a long 3/8 extension with a "wobble" socket on the end. If the nuts/bolts are very corroded you may have to hammer the socket on.

 

[BlackC55]

Also you may have to use heat to help it budge. They are tight so give it some welly.

 

[Dieselman]

If you really can't get the nuts off undo the manifold from the head.

 

[Tiff]

If you really can't get the nuts off undo the manifold from the head.

This would be the way I'd go too, you'll get a new gasket in the head set anyway, and the head is difficult enough to manhandle on your own without the manifold!

 

[spock500]

Yup, I didn't try getting mine undone as looked solid.

Undid manifold as DM suggests then held it back from the head using cable ties - not the same engine but similar OM605.

Good luck.

 

[jonn]

great thanks for that. So i just continue following the instructions without undoing the exhaust bolts then?

 

[BlackC55]

Use heat and more effort. Use a longer handled ratchet or bar. This will give you more leverage.

 

[alexander patie]

great thanks for that. So i just continue following the instructions without undoing the exhaust bolts then?

obviously you realise that the head cannot be removed without disconnecting the exhaust - either at the down pipe/s or manifold/head. if unbolting the manifold expect at least one stud to shear off, i suggest you persevere with the downpipe bolts.

 

[jonn]

Ok, thanks for that.

For the time being i have continued with the other instructions but am a bit stuck now on identifying the parts mentioned (this is my 1st attempt at this!!) .

Can anyone help with these:

(1) It says, disconnect any vacuum lines from the vacuum valves mounted on the cylinder head and inlet manifold. I assume this means the metal bolts attached to it highlighted in yellow on my attached picture?

(2) Unscrew the Union nut and disconnect the brake servo vacuum hose from the inlet manifold - which one is that?

(3) Disconnect the fuel supply from the return lines from the carburettor or fuel pressure regulator. where are these?

(4) where applicable unbolt and remove the EGR pipe which connects the EGR valve t othe inlet manifold - where are these?

(5) Some of the bolts have a strange shape on them - i take it these are union bolts and you need a special spanner to undo them. Where can i get one?

Many thanks if anyone can answer these.

 

[Dieselman]

That isn't the cylinder head, it's the fuel distributor.

What the instructions are saying is to undo any pipes that are linked to the cylinder head or inlet manifold so you can lift it clear.

The rubberised pipes you have circled are the fuel feed and return pipes, so need disconnecting, the servo pipe goes to the brake servo and any vacuum pipes are small diameter and go to small valves, etc.

 

[vijilants]

Are you sure you really want to continue with this job without handing it over to a skilled mercedes mechanic or having one to guide you ?

Things are going to get far more involved when it comes to disconnecting and re installation of timing chain sprockets etc.

Furthermore once you have removed everything, these cylinder heads simply do not just lift off and more often than not need a lot of messing around to get them to budge without causing damage to them.

The Haynes manuals does not replace experience when it comes to this type of a job and can quite often miss out on setup that can be critical. They are also written in a manner that appears to make these jobs very simple. The reality of it is they never are that simple.

If it all goes wrong you may have a very expensive repair / replacement of engine on your hands.

 

[jonn]

ok, i see thanks. so the whole bit is the cylinder head and i need to disconnect anything attached. Not many pictures in my book so hard to identify bits

 

[jonn]

I appreciate this maybe a bit more involved than i initially thought!

This is my old car, not everyday use so was hoping to give it a go

 

[Ian B Walker]

Look in the how to section, Ok its a 3 ltr but the principles are the same, just 2 extra cylinders.

http://www.mbclub.co.uk/forums/howto/63184-howto-change-head-gasket-12v-3ltr-m103.html

 

[spock500]

A good tip is to photograph everything twice from two different angles.

When it comes to reassembly you will find them invaluable especially if theres a delay putting it back together.

The cylinder head is the upper part of the engine block which the exhaust manifold bolts onto.

Just start to remove anything thats connected to it but take a snap as you do and post a stage photo every now and then on here.

But before you go any further have you disconnected the battery and drained the coolant?

 

[jonn]

yes, i have disconnected the battery and drained the coolant.

Starting to think i am taking a bit too much on!

 

[alexander patie]

Starting to think i am taking a bit too much on!

so sorry john, but i fear you are.

on this forum there are always plenty of people ready to help anyone and everyone with jobs both big and small. sadly however we can only do so much, the rest is up to you. the very basic questions you have asked show us that this will be a very steep learning curve for you, if not vertical . if you have time, patience, a warm garage and a determined nature then carry on. presumably this is not a car you expect to be driving any time soon? and if i may be so bold, why are you removing the cylinder head anyway?

 

[jonn]

It's a bit of a weekend thing at the moment and am quite enjoying it at the moment.

I've had my 190e for 12 years and used to do loads of small repairs to it but then the head gasket went and i bought a new car. My plan was to fix the 190 in my spare time and attempt to get it on the road again. The Haynes manual assumes a basic mechanical experience that i probably dont have but even so their instructions can be a bit vague. It's getting access to parts and losening rusted on bolts that are the main problem really

 

[Smiley]

Do perservere with it, just be very very methodical and careful and dont be afraid to ask on here and post some pictures to help get the right advice. Make sure that you have some half decent tools; you can not do this sort of job without a decent socket set for example. Dont force any components - unless you can see that they are rusty bolts of course. You will find that applying some heat to them will help a lot - and soak in penetrating oil for a few days.