trying to get head off 190e

[TheJim]

Hello chaps, it's been a while........ Hope you are all well!

I have not been around as my Merc has been giving me a lot of grief and ended up being taken off the road- But I am now trying to revive the old git.

I am attempting to get the head off at the mo as the gasket went, it has all been going wrong- snapped head bolts, you name it. I have now got everything disconnected and all the head bolts out, but cannot get the head to budge.

Any tips? So far I have been jiggling it about and hitting it. To no avail.....

 

[Mikesmerc]

Have a look to see if there are two small allen bolts tucked away at the front, where the timing chain passes through the head. Caught me out once. Be careful not to drop em into the sump. Head should release quiet easily.
rgds
Mike

 

[TheJim]

Nope, removed the timing chain cover bolts..... blighters to get out......

The only things holding the head on are the remains of two head bolts and 15 years of head gasket suction type forces.

I was clouting it with a hammer (and block of wood) near where the coolant temp sensors are and it was moving the whole engine but the head was staying put.

 

[Mikesmerc]

Jim, its not the cover bolts, these bolts actually hold the head tight to the block to prevent any oil leakage around the timing chain area. There might be one located at rear as well externally, ie outside the cam cover.
Rgds
Mike

 

[TheJim]

No, all the bolts are out. I know the ones you mean, they are the fiddly to reach ones about 4 inches down from the cam shaft sprocket that need an allen key rather than torx.
It really is seized on.....

 

[bundy]

re 190 head

did you remove the bolt that is on the left viewed from the front? just beside the temp sensor! it does catch a lot of people out. good luck.

regards bundy

 

[Mikesmerc]

Looks like you will have to use a piece of 4x4 timber and a lump hammer, then again, are these heads aluminium?, if so I would disregard my first suggestion.Cast iron heads are the only type I have taken off.
Good Luck
Mike

 

[TheJim]

It is an alloy head, still been twatting it though- to no avail.
I think Bundy is thinking of a different lump, the temp sensor is on the right of the head on mine......

 

[190D]

1/ Have you removed the 4 small bolts inside the head securing the head to the timing cover .



2/ Have you removed the 2 bearing bolts at the front of the head which supports the timing chain guide rail.

 

[TheJim]

Yes to one, and if by two you mean the pins that you have to pull out by threading in bolts and pulling them with a slide hammer, yes.
The only bolts that are still in are the headless remnants of two head bolts which I had to drill the heads off as the splines had broken off.

What I really want to know is how to unstick the head from the block. Is it worth trying to winch it out or something? The haynes manual suggests 'rocking it free', which is not much good as I have the stems of two bolts still in there!

 

[paulcallender]

Can you not replace the spark plugs, and use the starter motor to turn the engine over? The compression would 'blow off' the head. You could refit a couple of the bolts so that it didn't go too far, although I suspect it wouldn't anyway.

 

[JamieD]

I've had a similar problem with a saab 9000 with 3 knachered head bolts - I was told to drill them as far as I could down to through the head... still took two people a while to rock free though - I also sprayed wd40 down the shafts of the broken bolts...

wouldn't starting the car with the head partially on risk damage to valve / cambelt/chain? I've never heard of that tactic before and do quite a few head gaskets. Be interested to know if its tried and tested so i can give it a go next time ones stuck fast.

 

[TimN]

Have you removed the exhaust and inlet manifold. If so put them back on. Grab hold of the extremities and wiggle like hell. The extra leverage should separate the joint.

When you get the head off have it checked for distortion as you have not been able to release the head in the correct sequence.

I had a similar experience when an internal torx bolt rounded off. I was just abble to get a grinder in and take the head off. Of course the head was surrounded in cloth to pick up the swarf.

Don't suppose the bolts could be tapered in some way?

Best of luck

 

[paulcallender]

wouldn't starting the car with the head partially on risk damage to valve / cambelt/chain? I've never heard of that tactic before and do quite a few head gaskets. Be interested to know if its tried and tested so i can give it a go next time ones stuck fast.

Not if you have removed the chain, and either set the camshaft into a 'safe' position or removed the camshaft or other components, so all valves are up. If you're not sure of this, there's no harm in turning over the engine (1 complete rotation would do), to check. Obviously, you'll need to completely reset the timing afterwards.

 

[TheJim]

Don't really fancy turning the engine over with no timing chain, I don't want to have to replace my valve train as well!

I have tried waggling it, the inlet manifold is still attached as it is meant to come off with the head, so leverage is not a problem.

I will chuck some wd40 down the bolt holes though. It might help.

I used some sponge to block off the passages in the head and stop swarfe getting everywhere.

I am going to take the head to get it crack tested and skimmed if necessary. (when I get the bugger off)

 

[Mikesmerc]

Lots of WD40 around the sheared bolts and is there a lip at the side of the head that you could tap up using a block of timber and a hammer?. Took a head(cast iron) off a mini a few months back and it took hours of belting it with a hammer and timber to get it released, the gasket had blown from the combustion chamber through to one of the bolt holes building it up totally with carbon. Maybe this is why you bolts sheared.
Mike

 

[TheJim]

Good point, there is not much room to manouvre but I shall look for a lip. The carbon could explain a lot..... Time to get an industrial sized can of WD40!

 

[190D]

Could you not try a small jack between the engine mountings and the manifolds

 

[TheJim]

I tried a trolley jack under the inlet manifold and it was lifting the engine up alarmingly far. I shall have a look to see if I can get a bottle jack or something between the mounts, I think it will be a no go though.

 

[996jimbo]

Did you try belting it whilst jacking it up?

Or how about pouring hot water in to fill the block's water galleries to see if you can encourage a bit of differential movement between the block and the head, and jack it up and belt it with a hammer after applying loads of WD40?

Something would be bound to give anyway!