Flavorizer bars and burners on our old Weber S-310 (3 years old?) were completely corroded through, new one was $850 or so, so I decided to replace the flavorizer bars and the burners to delay a new grill purchase for a few more years. I didn’t take a picture of the old flavorizer bars, but here is a picture of the old burner tubes:
The old S-310 has the burner knobs on the right side table (the new model has them on the front), so you need to make sure you get the right parts. I got the wrong ones from Amazon, sent them back, and got the right ones here. The flavorizer bars need to be 24 inches, and then you need the right burner tubes.
Replacing the flavorizer bars is dead simple. The burner tubes are also simple, but there are some tricks.
To replace the burner tubes I think Weber assumes you will remove the manifold assembly (they even include two replacement bolts for same). If your grill is anything like ours, it is impossible to remove the original bolts without damaging other things, hacksaws and drills will be involved. Here is a picture of the offending bolts (with new burner tubes already installed):
Instead of taking those two bolts out, go to the other end of the burner tubes and twist them off the screws holding them in place. Then you can easily get vice grips on those screws (I used some liquid wrench to play it safe), take them out, and you should be able to reuse them with the new burner tubes. Without these “set” screws there is enough play in the burner tubes to remove them from the manifold and slide them out of the grill. Here are the new tubes in place, before reinstalling the set screws: