A mechanic has lost an arm and suffered severe cuts to his other arm, cheeks and neck after being mauled by a customer's two 50kg hunting dogs.

Brendan 'Bear' Clark, 43, was working on the man's car in the front yard of a property in Coonamble, central western NSW, about two weeks ago when he went to get something from a shed and saw two pig-hunting dogs staring him down.

Moments later, one had latched onto his left arm and the other to his right, and Mr Clark was in the fight of his life.

He told the Newcastle Herald the dogs had him on the ground quickly, and he realised they were trying to kill him.

Mechanic Brendan Clark (pictured) lost his arm after he was mauled by two pig-hunting dogs while fixing a customer's car

'One went for the face - he was heading for the throat, but he got a good bite on the face,' Mr Clark said.

'I realised he was the main aggressor. I grabbed him by the collar and gripped my fingers in to keep him away. He started chewing on my arm, and I thought - "You can have my arm, but you're not having my throat".'

Mr Clark said at one point he had one hand in each dog's collar.

While he was initially trying to choke them so they'd release his arms, they had soon injured him so badly all he could do was try to hold them off.

'I could hear the bones breaking and the meat being ripped off,' he said.

'They were eating me alive.'

Mr Clark was fighting the dogs off for up to an hour-and-a-half before the owner of the property, who was working in an office inside the house located 'a bit down the road', came to help.

The dogs were put down straight away, but not before they had taken the mechanic's right arm.

The horrifying ordeal has left Mr Clark suffering flashbacks that make him physically recoil, and an infection sustained during the battle means he is still fighting for his life.

His friend Jamie Everitt has launched a GoFundMe to help the mechanic with his medical bills, telling supporters Mr Clark was 'always willing to help somebody and put himself last'.

'A talented and skilled mechanic going about his work in a driveway of a customer, he was set upon by two very unwelcome dogs and as you can see he came off very second best,' he wrote.

'The fight he put up must of been horrendous to say the least.

'Brendan we love you mate and we want to see you bounce back to happiness mate. The bills are going to be extreme, let alone doing everything left handed for a long time, so lets donate to a wonderful human being and top mate.'