Mercury 250 Pro XS Review

Originally published in TrailerBoat #287, October 2012.

To sell a boat engine in the US it must have EPA (Environmental Protection Agency) 3 Star emissions compliance. Unlike the cooking model Mercury OptiMax 250 sold here, the Mercury Pro XS is a 3 Star engine. That means nothing to us Australians as we’re not so influenced by the greenies (yet!). What it does mean is that its 3 Star compliance gives the Mercury 250 Pro XS incredible bottom-end to midrange fuel efficiency.

MERCURY 250 PRO XS

As with all Mercury OptiMax outboards, the 250 Pro XS utilises the Orbital Combustion Process developed by WA’s Orbital Engine Corporation, with a mix of stratified and homogenous combustion. I won’t go into detail about the OCP process here, but I will say that in this instance it results in an engine that is remarkably affordable to run.

This 3032cc, loop-charged, 60° V6 was designed specifically for marine usage, and it develops 250.7hp at 5750rpm with a Wide Open Throttle (WOT) range of 5500 to 6000rpm. A 60A belt-driven and voltage-regulated alternator provides plenty of power for onboard electronics. The gear ratio is 1.75:1 and the dry longshaft weight is 229kg. Being a dedicated performance engine it has a cooling water intake low on the gearcase for use with a hydraulic jacking plate.

Powerhead access is good, with a large-capacity 11.4lt in-boat oil tank supplying the variable-ratio oil injection. Mercury recommends servicing the 250 ProXS annually or every 100 running hours after the first service at 20 hours. Providing the service is carried out by an authorised Mercury service centre, the recreational-usage warranty is five years.

ON THE WATER

Perhaps it wasn’t so good for Mercury that on the same day I reviewed a Bullet 2100 powered by a Honda BF250 outboard. Admittedly the longshaft Mercury 250 Pro XS had solid engine mounts, transferring engine vibration through the 1850, but there was some harshness on transition from stratified to homogenous combustion, whereas the Honda outboard was beautifully smooth everywhere.

The exhaust note was way louder than that of the Honda, with the typical Mercury V6 “howl” evident from midrange upwards, but I love that howl because to me it symbolises raw power — and the Mercury 250 Pro XS has plenty of that. Its holeshot is just stunning (less than two seconds to plane from trolling rpm) and even when you’re cruising at 4000rpm you simply have to hang on for dear life when you give it some stick.

Driving the Mercury 250 Pro XS outboard is just a matter of lowering the jacking plate to give the 25in-pitch Quicksilver Laser 11 stainless steel prop some bite to get out of the hole, then progressively raising it. Through tight figure-of-eight turns at 3000rpm there’s no prop ventilation and at midrange rpm the leg trim can be left neutral. As rpm increases you trim out the leg, especially when running downwind. The rooster tail shoots skywards and you get the rush that every well-set-up performance boat should deliver.

MERCURY 250 PRO XS PRICE

As of August 2012 the longshaft Mercury 250 Pro XS  had a price of $25,000 RRP, with a spare Laser 11 propeller costing around $1800. The review engine was supplied by Cove Marine, Oyster Cove, NSW, who you can reach on (02) 4982 4832 or mail@covemarine.com.au.

THE TRADE-A-BOAT VERDICT

I’ve always been a two-stroke engine bloke and to me DFI just makes a two-stroke outboard motor even better. I just can’t go past the combination of instant power delivery, reasonably light weight and inherent simplicity. I’ve long been an Mercury OptiMax convert and the Mercury 250 Pro XS just reinforces my belief that when you want that adrenalin rush, nothing beats a DFI two-stroke!

MERCURY 250 PRO XS PERFORMANCE

Pushing 1000kg including three adults

COMPETING OUTBOARDS