could anyone help i have a lackland male3year old and a jackrussell male 1year old they got on fine till a few weeks ago now the lackland keeps actacking the jrussell

Any sudden change in behaviour should be checked out with a vet to eliminate physical reasons.  It's possible this behaviour is part of the heirachy establishment, and so long as no body needs vet treatment for injuries, I'd leave them too it, or try and identify what triggers the attacks and modify their routine to eliminate the triggers.

we have try letting them fight it out but the jrussell was getting rip 2 bits

"It's possible this behaviour is part of the heirachy establishment,"

Yeah....you can't let your dog get ripped to bits. Good heavens! The heirachy establishment is...I don't allow that behavior in my establishment! The dogs must respect MY rules, not theirs.

If blood is being drawn they're serious, and it must be prevented. Are they both entire?

The problem with letting terriers 'fight it out' is that some (particularly from working breeding) will take a huge amount of punishment before they back down (and some will never back down).

Unfortunately with some terriers the only answer ends up being to keep them totally apart. Without seeing them together its very difficult to know if there is much you can do.

we havent work any of them but we no the parents 2 the lackland were working dogs 

Many terrier breeds have a reputation for being 'sharp' - they were all designed as vermin-killers after all, so being fast with their teeth was seen as a positive benefit.

Which of the two starts the fights? I see you said the Lakeland attacks the Jack, but under what circumstances?

we have had someone 2 see the dogs and she say it will be the lackland letting the jack no he is the boss he can attack any time even if the jack gets 2 the door first

Just out of interest, who has been to see the dogs? I'm hoping it was someone your vet referred you to.

yes it was one the vey gave us she was at my house 4 1 and half hours

the lackland as been castrated we haven had jrussell done

Ops!  :(  Sorry, I've only just seen the additional replies to this thread.......  I was afraid you'd say damage was being done because they are both terriers.......  Sometimes the younger dog just won't back down, and as they are now both castrated, there is very little you can do to alter their natural status :(

the jack russell hasnt been castrated