Barrel stuck in head - best removal technique?

[Bob Edwards]

Haven't removed 2cv heads before so thought I'd practice on old spare engine. Barrel stuck in head. What's the best way to extract without damage, please? Haynes book makes no mention of 'stuck solid'! Is this usual with 2cv heads or are they normally easier to part?

I notice this engine hadn't been stored well before I got it - some rust in barrel. Also notice partial seizure marks on barrel and piston, Would like to salvage head though.

Cheers, Bob

[Ken Hanna]

Bob,
heat applied either with a blowlamp (or domestic appliance at your own risk ) plus penetrating oil or WD40 into the joint can help get things moving.

However, I usually go direct to some brute force, with a section of 50 x 50mm timber cut to a length which leaves 'about' 75mm poking out of the barrel.
To steady the wooden drift in the bore, wrap cloth around it.
Grip the barrel in a gloved hand, with the cylinder head hanging downwards over a soft landing surface and clout the protruding end of the piece of timber with a lump hammer.
It usually doesn't take more than a few thumps to loosen the grip...

Haven't removed 2cv heads before so thought I'd practice on old spare engine. Barrel stuck in head. What's the best way to extract without damage, please? Haynes book makes no mention of 'stuck solid'! Is this usual with 2cv heads or are they normally easier to part?
I notice this engine hadn't been stored well before I got it - some rust in barrel. Also notice partial seizure marks on barrel and piston, Would like to salvage head though.
Cheers, Bob

[SILLYCVS]

Concur with Mr H, if lump hammer dont fix it, itll be electrical problem lol

[Bob Edwards]

Thanks both for advice - lump hammer won. Box on floor filled with rags to catch head. Wooden block down centre of barrel didn't separate them, but direct tap to bottom fin of the head, where two fins are strengthened by a pillar between them, worked. I'd pickled the joint in wd40, which may have helped too. The other head separated from the barrel as they were being removed from the crankcase, so no problem. This spare engine is pretty poorly.

I've got the parts for a top end service on the way for the engine that's in my Lomax. I'd done a compression test on this the other day and both cylinders read about 110psi dry and 120psi with a squib of oil in each pot. I read elsewhere a Dyane engine should read around 175psi, so as I bet the heads haven't been touched in the last 20 years its time for some tlc. Lomax runs well, so it'll be interesting to see if a difference is noticed.

[stevegrimes]

I had this issue on both barrels.
A suitable sized lathe and 4 jaw chuck worked a treat.
block of wood down the centre and a bit of brute force.
Being careful not to hit anywhere near the valves