Pleading 'Have you seen this spaghetti western?'

Apologise if you guys get fed up naming films others have forgotten the titles of.

However not seen this film for a long time (20 years) and I am looking for a copy on DVD if possible. Due to the ludricrous nature of what is in it I would hope that you guys may be able to name it pretty quick.

It features an old guy who has a donkey with a deckchair mounted on its back instead of a saddle. He is either riding with or keeps coming across a couple with a covered wagon who have a baby with terminal flatulance because they only feed him beans.

Thought it was hilarious when I was about ten would like to see it again if only I knew what it was called. Your help would be much appreciated.

Baby with flatulence? I know one:
Trinity is still my nameà