There are two locations for oil on the Mercury. The first is the stator, and the second is the gear case. The job can be done with basic hand tools and should only take a few hours in total.
Start by soaking everything with penetrating oil a few days in advance.
To change the impeller.
Disconnect the steering and shift cables.
Remove the four bolts holding the nozzle on and remove it as an assembly (nozzle and reverse gate).
Remove the two screws securing the trim plate to the ride plate and wear ring. Leave the two adjustable screws on the stator alone.
Remove the four bolts holding the stator on and remove it with the trim plate attached.
Remove the intake grate. *NOTE* if it is still a hydro surge grate replace it with a fixed grate at this time.
Hold the drive shaft with a wrench and remove the impeller nut.
If you replace the wear ring be sure to replace the two "O" rings on it.
Replace the stator seal.
When reinstalling be sure to coat the impeller shaft with Mercury special lube 101 or equivalent.
torque specs for the bolts are.. 35 lb.ft for the stator and wear ring bolts. 150 lb.ft for the impeller nut. The two six mm intake grate screws 75 lb.in. The two eight mm bolts 16.7 lb.ft and 75 lb.in for the two ride plate screws. Be sure to coat the shafts of all bolts with special lube 101 and use blue loctite on the threads.
Refill the stator with 550ml of Mercury HP gear oil.
The gear case is much harder. Lay under the boat and you will see two plugs in front of the intake grate that come out with a large blade screwdriver. Place a drain pan under them and remove them both. *NOTE* they both have rubber washers tat seal them, DO NOT LOOSE THEM. Now go and drink a beer or two while it drains. Now refill the gear case through the center plug with 825 ml of Mercury HP gear oil and replace both plugs.
See this thread for part numbers for the intake grate and after market impellers.
http://www.seadooforum.com/showthread.php?t=10926
Aaron:cheers: