Will neuturing a cat make him not spray?

Because they do all this stuff!

I have owned cats for years and have never had one spray once neutered

Yes as long as it's done BEFORE they start.

It should, but I know if he isn't neutered the spraying will get worse and then it will be a way of life after he is neutered.  It is best to have this done as early as possible. 

all I know is it is better to get male cats desexed before they reach sexual maturity and start roaming looking for females.

It will decrease the desire and need to, absolutely, however, it's not 100% completely effective if, say, the instinct kicks in. If he's around unspayed females or there are other cats/animals outside threatening his turf, or even if you bring a new kitten in, he could start spraying just like *that.* Not likely, but it *could* happen. I have two boys, never sprayed a day in their lives. I still know that it *could* happen if something drives them to it.

Not always.   If he already started spraying.. Neutering wont stop it

It will cut down on his desire to mark his territory. As long as you don't add an unspayed female to the mix he probably won't spray. Neutering them when they're older doesn't have as good an effect.

Neutering will stop spraying, and all kinds of other unwelcome behaviour. Unfixed cats will fight, and be very territorial. You are doing the right thing.

Neutering doesn't change the cat's plumbing.   He can still spray after he's neutered.

However, removing the testicles removes the source of the hormones that is often the cause of territorial spraying.

Neutered cats sometimes still spray.   Even spayed females can spray.   If the cats are angry or feeling crowded by another cat or are experiencing pain (as with a UTI or cystitis), they may spray.

Short answer?   Probably will not spray.   Physically can still spray.