AJS & Matchless Owners Club

Hi

I'm trying to remove the barrels from the crankcases on a non AMC machine , (but the principle will be universal). I've tried heat, soaking in diesel, sharp taps all around and jacking with a purpose made tool - none of which are proving successful

The barrels have been undisturbed from new, 40 years ago, and I think its just 'sticktion' of the gasket holding things together. Can anyone suggest something to penetrate the joint and ease the process? The last thing I want to do is damage them during removal.

(Its a T160V)

Regards Mick

The barrel lower spigot is perhaps being gripped by the c/case mouth.
Seems you've done all the usual things.
No doubt you've considered it but don't want the faff or to go to the extreme of loosening the c/case halves a tad.

Hi Sprid

Got it in one - don't want to start splitting the crank cases yet. According to the manuals the barrels are fitted after the cases are torqued up so they should slip out.

Annoyingly I could have left them in situ but when undoing the base attachment nuts several of the studs have come up with the nuts - now I need to remove the barrels to get the nuts off the studs and re-fit them, (studs won't come out until the barrels are off).

Regards Mick

Assuming that the head does not use the same studs as the barrel, have you tried undoing the cylinder retaining nuts, replacing the head and the plug and cranking the engine. This should break the seal

Cuh! That cantankerous Edward Turner, eh? Probably designed it like that deliberately.

Mick D wrote:....several of the studs have come up with the nuts - (studs won't come out until the barrels are off).

Does your 'purpose made jacking tool' involve undoing the studs and nuts until they bear on the fins (and snap them off?)

Bit random but, with the studs coming up they havn't jammed in the bottom of the barrel and "stuck" the barrels down?

Does the engine turn over? If not then the pistons are seized so need just leaving and let diesel or the likes soak in. If the engine does turn over do as Les says. Barrel nuts off or very loose WD 45 soak the studs. Head bolted on with valves and plug fitted. Kick the bike over, let compression do the job. Mat need a bot of encouraging by tapping the barrel high up with a rubber mallet to help break the seal. I always do that even if left for just a year, save putting the head back on again if the barrel seal is stuck. Sometimes even needs the mallet touch.

you could try filling the crankcase with paraffin and turn it upside down and leave for a week , and also perhaps drop the engine upside down into a bucket of paraffin [heating oil ] and leave it submerged for a week or so and then get a mallet and bit of alloy bar and give various areas of the barrels a tap about and then put the thing back into the paraffin again .
it may be possible to keep doing this until a gap forms where the gasket or whatever is still stuck and you will find it comes easier to make movements until you eventually get the bits apart .

when i have had seized up wastegates on turbos at work , i have heated them up and then immediately dunked them into a bucket of water and they then free off , it might seem severe but works , although i havent dont this with barrels yet but i do have a pair of 500 barrels which have a pair of pistons down inside them to remove which are difficult .

some people have used a hot bath of paraffin and soak the assemblies , or a bath of hot water and do same , a galvanised tin vessel and either a fire or gas burner is handy here .

so long as you dont go above the normal kind of engine running temp it should be fine whatever you do with heating .

hope you sort it
ian

Thanks All

Here's my 'purpose made tool' - it's jacking against the head attachment studs, which do not extend into the crankcases:
I'm off to Screwfix to buy more 12mm threaded bar so as I can add two more 'beams' to the outboard studs and continue trying.

If that fails I'll get a bigger nozzle for my propane torch.

Continuing to soak with diesel, (well Jet A1 actually), by paint brush - don't have a large enough container for immersion.

Continuing to tap all around.

Continuing to hope.

All suggestions welcome

Edited to add - the engine turns freely

Thanks Mick

Forgive me if I've misunderstood but I think this is a different way of doing your jacking. I would be wary of it because of the risk of damage to the fins above but if all else fails...........

It does require a gap above your cylinder studs to fit oversized nuts and spacers, a very gentle hand and a lorra lorra nerve. Then as you turn the nuts off,they push the oversized nut and spacer upwards, theoretically gently forcing the barrel away from the crankcase.