After a shaky start from the visitors - in which CONSUR took a 7-0 lead - the giant No.8's power game was too much for the hosts, plundering three tries of England's five first-half tries.
Stuart Lancaster handed first international starts to seven at the Estadio Charrua and but was also reminded of the potency of the most experienced man on tour - two-try full back Ben Foden.
Skipper Tom Wood and replacement Paul Doran Jones added England's other tries but with the hosts scoring three converted tries of their own and dominating the final 20 minutes, there remains some work to do with two Tests against Argentina looming on successive Saturdays.
The hosts, comprised of players from Uruguay, Argentina, Chile and Brazil, started with expected intensity but squandered their first two chances to take the lead. Benjamin Madero has already pulled a penalty chance wide before Henry Thomas was pinged at successive scrums, only for the Argentinean fly half to again drag wide on nine minutes.
But CONSUR soon took the lead, with referee Joaquin Montes awarding a penalty try after Jonny May deliberately knocked-on with England under huge pressure on their try line. The field position was made by a scything break from No.13 Francisco Sansot and with Gloucester man May also sent to the sin bin on his first senior start, Madero gleefully booted CONSUR into a 7-0 lead.
That try was the shock England needed as the visitors took complete control of possession and territory - and the scoreboard. After Myler fizzed a pass for the onrushing Foden to stretch over in far right corner on 19 minutes to get England off the mark, Billy Vunipola took over with three tries in quick succession.
At 128kg, the London Wasps 20 year old takes some stopping and it proved too much for the CONSUR pack on 29 minutes. Vunipola was the beneficiary at the back of the scrum after a line out catch and drive before adding a simple second three minutes later.
Then on 35, sin bin returnee Jonny May found Kyle Eastmond, who neatly offloaded to Vunipola, leaving the big man saunter over - with a slightly embarrassed expression on his face - and complete his treble.
As half time approached, captain Tom Wood added England's fifth try, profiting after a neat pick and go from scrum half Richard Wigglesworth created the space for him to crash over. Myler converted three of his five conversion attempts - two from wide on the touchline - to make the score 31-7 at the break.
CONSUR replied with a fine try soon after the restart, Madero chipping the ball over the top to No.12 Juan Socino, who in turn offloaded to scrum half Tomas Cubelli to race under the posts. Madero converted but almost immediately normal service was resumed, with Foden popping over for his second after Kearnan Myall was hauled down inches short.
After a lull in England's attacking play- perhaps after Lancaster made a host of substitutions - one of the replacements, Paul Doran Jones scored England's seventh try, taking advantage of more forward dominance to rumble over from close range after another positive catch and drive.
CONSUR came back into the game in the final 10 minutes - with replacement prop Alex Corbisiero sent to the sin bin after back-to-back scrum penalties - and were rewarded with the try their persistent final quarter attacking deserved, replacement lockDiego Magno powering over from close range to complete the scoring.
England now travel to Salta tomorrow morning to prepare for the first Test against Los Pumas on Saturday, June 8.
Sudamerica XV vs England teams
Sudamerica XV: Tomás Carrió: Belisario Agulla, Francisco Sansot, Juan Socino, Leandro Leivas, Benjamín Madero, Tomás Cubelli; Bruno Postiglioni, Arturo Ávalo, Mario Sagario, Cesar Fruttero, Pablo Huete, Tomás de la Vega, Javier Ortega Desio, Antonio Ahualli.
Replacements: Óscar Durán for Postiglioni 51, Nicolás Klapenbach for Sagario 51, Diego Magno for Huete 55, Juan Gaminara for Furttero 61, Agustín Ormaechea for Cubelle 71.
Scorers: Tries: Penalty try, Sansot, Magno. Conversions: Madero 3.
England: Ben Foden (Northampton Saints); Jonny May (Gloucester Rugby), Luther Burrell (Northampton Saints), Kyle Eastmond (Bath Rugby), David Strettle (Saracens); Stephen Myler (Northampton Saints), Richard Wigglesworth (Saracens): Joe Marler (Harlequins), David Paice (London Irish), Henry Thomas (Sale Sharks), Courtney Lawes (Northampton Saints), Kearnan Myall (Wasps), Tom Wood (Northampton Saints, captain), Tom Johnson (Exeter Chiefs), Billy Vunipola (London Wasps).
Replacements: Rob Buchanan (Harlequins) for Paice 50, Alex Corbisiero (London Irish) for Marler 66, Paul Doran Jones (Northampton Saints) for Thomas 50, Dave Attwood (Bath Rugby) for Lawes 61, Matt Kvesic (Worcester Warriors) for Wood 50, Lee Dickson (Northampton Saints) for Wigglesworth 53, Jonathan Joseph (London Irish) for Eastmond 59.
Scorers: Tries: Vunipola 3, Foden 2, Wood, Doran Jones. Conversions: Myler 3.
Yellow cards: May 18, Corbisiero 71.
Referee: Joaquin Montes (URU)