That size engine normally in a Lawn Tractor , 26-30" Deck Range that I recall . I suppose it depends on how well maintained the engine is and the power loss from the Mower Deck Drive Design . Not really that big of a engine , 10-12 HP more common on the smaller tractors today , considering the power draw of the tractor itself lol .

7 horses usta pull up to 36 inch decks just fine. We built a bunch of 'em. Ground drive by itself usually only takes a hp or two unless yer heavin one of those 1/2 ton big boys around... beyond that, hp is kinda a relative thing given the way the marketing boys like to spin things these days.

Net Torgue Ratings have replaced Horse Power Rating due to marketing policies and because Net Torgue on these small engines is a more valuable indicator of Performance . I agree that a Tec while an Older Design will produce more real life Grunt than a conventional Briggs of same displacement . 36 " is pushing the envelope , but may work if you don't have any strong elevation increases while mowing . If you look around the current smaller Tractors running over 30 " decks have larger Singles or even Twins !!

FWIW, I wouldn't even try to use 7HP on a riding mower. Put it on something to pull a cart or like that. I've got a Roper with a 12HP Briggs with a 38" deck and it struggled. Removed the deck and it's permanently connected to my garden cart now.

exmar - what you need is a good 'ol hit 'n miss classic ... very easy on gas and a quiet muffler - run all day long.

Just FYI; I had a MF 7, 7 HP Techumesh. It had a 32" deck. Things went bad when the engine wore out and I put the only engine on that I could find, a Briggs 11HP......

Think exploding rockets.....

But that's another story....