Tohatsu launches gas outboard
Propane power offers a cleaner alternative to standard petrol engines
Twenty years ago, LPG conversions to big petrol-engined boats were all the rage, promising vastly reduced running costs with little loss of performance. Some people swore by it, other people swore at it, but ultimately, the project was doomed, mainly due to lack of dockside supply and the amount of space that the large pressurised tanks took up on board. But reliability was also an issue.
Well, now it’s back, but in a vastly different form. Tohatsu has launched a purpose-built propane-powered outboard engine, and the supply problem has been solved at a stroke by using the sort of portable domestic cylinders typically used for gas barbecues and patio heaters. At 5hp, a domestic bottle is all you need rather than the massive tanks of old. The motor uses about 1kg of propane an hour at cruising speed, so a 13kg bottle at about £25 will give a running cost of roughly £2 an hour.
Based on its 5hp petrol outboard but adapted for LPG, the motor features a different material for the valve seats, the common area of failure with previous conversions to older engines. The main benefit for the end user is low emissions. Back to back with its petrol equivalent, Tohatsu says that the propane-powered motor produces 56% less carbon monoxide and 30% less hydrocarbon and nitrogen oxides than its petrol equivalent. In addition, there is no chance of fuel spillage and the fuel allows semipermanent storing as propane does not deteriorate with age like petrol.
Available in standard, long and ultra-long shaft versions, it’s also fractionally quieter, requires less maintenance and despite producing slightly less torque, Tohatsu claims it will give similar boat performance to its 5hp petrol motor. Prices for the new engine start at £1,269. Contact www.tohatsu.co.uk
Like Lehr’s propane-powered outboards, Tohatsu’s new engine uses a standard barbecue gas bottle