He isnt too old to be trained dont worry
How big is the crate? Is it just big enough for him to sleep in or does he have more room to wander around?
The point of crate training is that they will see the crate as their nest, the place where they sleep.
They will not want to go potty in the place that they sleep, But if he has enough room to go potty away from his bed in the crate then he will.
You need to make sure he only has enough room for his bed in there, If he needs water in there a few people have suggested water bottles like the type you use for rabbits which hang on the side of the crate (you can get some pretty big ones).
If you really arnt having luck with him going outside you could try potty pad training.
The pads are scented which will make him want to go potty on it, once he has that nailed start moving the pads closer to the door then eventually outside.
Remember to give him lots of praise when he goes potty in the right place and give him this praise as hes doing it or he will not know what he has been praised for.
Tell him off if you catch him doing it in the wrong place then show him where you want him to do it. Never tell him off if you have just found poop or wee on the floor after he has done the act as he wont know what he is getting wrong for. Good luck