It seems Gilbert is always forcing Beaver to think things his way like telling him to sneak him into a movie, make a face in the class pic, encouraged him to fly the kite before it was ready, informed Beaver about a movie on TV that would help him write a book report, told him to spoil Wally's party with pranks etc. so did Gilbert ever help Beaver to do the right thing?

He's a snake in the grass. Two more examples: when Ward and June confronted the boys after Beaver called the police after they spotted Clarence in costume outside, Gilbert lied while Beaver told the truth. Also, he urged Beaver to use Ward's golf club.

Larry was about the same, but at least he was more comedic.

Right. When I start to hear Gilbert telling Beaver how he should handle a situation and Beaver listens to him, I think back when Gilbert baited him to make a face in front of the camera. Beaver got himself into hot water with everyone. Beaver still continues to listen to his advice. Like when he told Beaver to stand up for his rights, how he was always left out of things cuz he was the young brother.

I think all of Beavers friends were essentially weasels who all gave gullible Beaver bad advice, Gilbert being the most offensive. Whitey with climbing the soup billboard , Richard with the monster shirt , Terry at the awards dinner all come to mind

Gilbert may me a snake in the grass, but Beaver is dumb enough to go along with him, and Larry, and Whitey (talking him into checking out the soup), and Eddie as well. If Beaver wasn't such a pushover, Gilbert wouldn't be able to talk him into things.

You got that right, Beaver never learns. Sometimes he's as dumb as a bag of rocks.

Dumb, even today...he should have talked to Mrs. Rayburn before he went home and upset everybody. Had he done that, he would have found out about the separated diploma. Of course, we've discussed this kind of thing before--then the episode would have been short by 6 minutes.

Right. When I start to hear Gilbert telling Beaver how he should handle a situation and Beaver listens to him, I think back when Gilbert baited him to make a face in front of the camera.

I think you just put your finger on why they named him Gilbert "Bates" (baits).

An episode where I find Gilbert downright repulsive is "Poor Loser" where he influences Beaver to become resentful about being the younger brother. You've got to ask yourself, why is he so adamant about changing Beaver's mind about this?

Yup and why does he keep after Beaver until he watches the movie, The Three Musketeers with the Ritz Bros. Why did Gilbert have to show up at the house and convince him to watch? I know so Beaver will get in trouble.

However in Beaver's Good Deed Gilbert does say "Golly Beaver a bum." Then tries to persuade Beaver to not let him in.

...when Gilbert baited him to make a face in front of the camera.

Gilbert Baits? That may be why his name was changed from the original Gates.

Beaver being prodded into doing something he shouldn't by both his friends (Larry, Whitey, Gilbert, Richard, Terry) and his enemies (Eddie, Lumpy) was a story structure they used often on LITB. You would think Beaver would eventually learn not to fall into this same trap week after week but he never really did!!

Even when Gilbert wasn't at fault he would leave Beaver in the lurch and run away. Like when he left Beaver sitting in the car in the road and Gilbert ran away.

The car in the road was another pretty well-played, well-written scene. That was probably the only time Gilbert wasn't to blame.