Hi,
RV150 refers to the engine type, not the mower. All current mountfield mowers with this engine have several height adjusters - one for each front wheel, and either one for each rear wheel, or one lever that adjusts the whole back axle assy. Just make sure they are all at the same height!
Phil Saunders
(phil_saunders(a)bigfoot.com)
Phil Saunders, June 2013