we(well my brother) tryed to take the 2cv heads off(he,s building a special) but they are stuck solid, so he took the head and barrells off instead and took them into the w/shop
he tryed to separate the 2 but no matter how hard he tryed the head and barrel won,t separate
the book reckons they come apart easily---h,mmmm

When you say, taken the heads and barrels off:
Did you remove the head nuts, remove the heads and barrels leaving the 'rods' in place... or have the rods seized into the headnuts meaning the whole shaboodle has been taken off.... although that seems unlikely...

Pics?

It can be a bit of a struggle ... you might need to (VERY GENTLY!) lever the barrels off the heads with a broad bladed flat screwdriver. But be very very careful not to break the fin on the barrel.

So you have the heads and barrels on the workbench but they seem to be stuck together.

I would guess that someone has been tinkering previously and have used some sort of sealant between the two parts which has now set solid.

You don't want to wreck the heads as they are the expensive bit but if your going to replace the barrels anyway I'd grip these in the vice for starters.

You could use a bit of wood through the middle and give that a smack, or perhaps try rotating the heads off with blows from a rubber mallet.

you need the special tool

DSC00062 by Sean602, on Flickr
and a hammer
hold the barrel and head and smack the timber with favourite percussive tool

I'd avoid both levering with screwdrivers and bashing the heads with a mallet, instead pop the head/barrel combo in an oven set to 160*C ( Gas mark 3) and leave it to get up to temperature.
In the meantime. cut a piece of 50 x 50 timber about 200 mm in length and round off one end, also dig out your welding gloves and a lump hammer, plus some cardboard to keep the timber drift sitting central in the barrel.
Remove barrel and head from oven, hold upside down over some old carpet or anything else which gives a soft landing and give the end of the timber a few good thumps.
Pouring some light oil into the barrel seems to help free the grip of the rust as well and if you use sunflower oil, instead of mineral, that might reduce the punishment meted out for unauthorised use of the oven...

ken

( B@gger, see that Sean chose the expurgated/condensed version... )

Toes not recommended!

thanks so much for the replys folks, theres a bit too much info for me to reply too so ill print it all out and give it to graham (my brother)
(btw, i was thinking of the lengh of wood down the barrell )

the heads are more or less scrap as the threads are all cream crackered, he has another 2 good heads that steve diment is going to give/sell him
hope my printer fires up
thanks ken &all
andy
all printed

thanks for the advice fellas , the oven method did the trick

Hi Folks, Does anyone happen to have the dimensions of the special tool as shown in the above photo..... .....looks complex, is the rag attached?...does it have to be that specific type of rag/wood combination....???...