"A lot of the people who are doing the complaining and saying, why isn't anything getting done -- maybe they ought to look in the mirror," Kasich said.
"What have they accomplished?" he said. "I mean, are they just speech-makers? Are they just people out there yelling and screaming?"
Kasich chalked the criticism Boehner -- a fellow Ohioan -- has faced internally up to "inexperience."
He said Boehner played an important role in the 1990s, when Kasich was the House's budget chairman and the United States ran a surplus.
"And Boehner sat at the leadership table right next to me and we pushed those things through and that was some of the most productive time that Republicans or conservatives have had," Kasich said.
Boehner himself lashed out at "false prophets" in the right's ranks, blaming them for political strategies that "never had a chance" even while taking the government into fiscal crises.
"Absolutely, they're not realistic," the retiring House speaker said of hard-line conservatives and outside groups in a Sunday interview on CBS' "Face the Nation."
He pointed to the October 2013 shutdown after conservative House Republicans demanded the repeal of President Barack Obama's signature health care law as one maneuver -- led by Texas Sen. Ted Cruz -- that was never going to succeed.
"The Bible says beware of false prophets. And there are people out there, you know, spreading noise about how much can get done. I mean this whole notion that we're going to shut down the government to get rid of Obamacare in 2013 -- this plan never had a chance," Boehner said.
Kasich's support for Boehner is at odds with Cruz, a fellow GOP presidential candidate, and might be a hard sell to GOP primary voters. Outsiders like Donald Trump and Ben Carson lead current polling
, suggesting the party's base is looking to reject establishment politicians like Boehner.
Cruz reveled in Boehner's surprise decision on Friday, telling a groups of conservatives gathered in Washington, "You want to know how much you terrify Washington? Yesterday, John Boehner was speaker of the House."
"Y'all come to town and somehow that changes. My only request is: Can you come more often?" he said.