12
Mar
Remove the four bolts holding the water pump together from the water pump housing with a socket wrench. You need some long reach neelde nose pliers to get at it.
So now that you have the lower unit removed on your Mercury Tracker 25.
Remove lower unit mercury outboard. I did this on a 1984 20hp Mercury elec. This video will show you have to remove the lower unit and change the water pump impeller on a Mercury outboard motor. Remove the trim tab bolt and the trim tab followed by the 15mm lower unit mounting bolt hidden beneath the trim tab.
Support the lower unit to prevent it from dropping and remove the four 16mm lower unit mounting bolts from around the top of the lower unit. Im trying to remove the lower unit of a 200 hp mercury optimax. I cannot seem to get the unit to come free.
I have removed the 4 nuts and the bolt going to the corrosion protection on rear. LOWER UNIT REMOVAL DISASSEMBLY. Always disconnect the battery cable before removing lower unit.
Shift to NEUTRAL position. Remove bolt and trim tab 1. Remove seven 7 bolts 2 and separate gearcase 3 from driveshaft housing.
Remove clutch rod from clutch shaft if necessary. Place a drain pan under oil drain plug. Sierra 18-2244 Drain Screw.
Sierra 18-2244 Drain Screw for Mercury and Mercruiser This Sierra 18-2244 Drain Screw is for use with the following. Mercruiser I R MR Alpha One TR TRS all OBs with 38-16 non-magnetic gear lube fill or vent screws. Support the lower unit as you remove the fourth 19mm nut and washer so the lower unit can only drop a few inches.
Reach into the lower unit and release the speedometer tube at the front. Remove the lower unit from the outboard and youre done. Merc recommends removing the lower unit on an annual basisto service the water pump but also to lube the splines on the driveshaft and the shift-shaft and the studs on the lower unit.
You are going to have to use wedges between the lower unit and the driveshaft housing to try and pry the lower unit off. Use the socket wrench extender and 916-inch socket to remove the hidden bolt holding the lower unit in place. Pull the lower unit away from the rest of the motor twisting the lower unit if necessary to free the drive shaft and shifter.
Use appropriate caution when removing the unit and wear safety shoes. As noted the steps for removing the lower unit from a Mercury 40 2-Stroke outboard are the same or similar for most small-to-medium sized Mercury motors. However if you want to see the gearcase removed on a 4-stroke model watch the video above to see how to remove the lower unit on a 2003 Mercury Tracker 40HP 4-Stroke engine.
I have removed lower units from Evinrude Johnson and Yahmaha outboards and hade to disconect shift shaft by undoing threaded rod. Dont see any such feature on this Mercury. The only way I see to free shift rod is to remove shift lever arm underneath cover aft and below of carbs.
Shift outboard into FORWARD gear. Tilt outboard to full UP position. Remove shift shaft retainer.
- This is located under the carburetor tucked in close to the engine block. It is hard to see and hard to get to. You need some long reach neelde nose pliers to get at it.
Remove reverse lock actuator. The lower unit on Mercury outboards must be removed to change the water pumps impeller. Replacing the lower unit is part of replacing your water pumps impeller exchanging a drive shaft of one length for another length or replacing the oil seals on drive or propeller shafts.
Lower unit disassembly of a 15 HP mercury From one DIY to another I understand youre anticipation to find the problem and fix it. However this is usually where you want to step back assess the situation completely and proceed cautiously. I dont know when Merc gave up on that ridiculous design flaw and went like OMC had been doing for years with a corrosion resisting stainless steel drive system.
If the latter here is the case Google separating the lower unit from the mid section on outboard motors and you should get a lot of answers many of which are addressed right here on. Take out the bolts that connect the lower unit to the exhaust housing with a socket wrench. Slide the lower unit straight down and off the outboard.
Set the lower unit upright in a bench vise. Remove the four bolts holding the water pump together from the water pump housing with a socket wrench. Oct 3 2011.
2004 Mercury 115 ELPT Lower Unit Removal. One nut at front of LU near the shift rod. Two just back that attach on top.
Two more under the plate. Remove anode for the 5th and one more underneath where the anode came off. You noted 5- there are 6.
Support the lower unit to prevent it from suddenly dropping then remove the four 16mm lower unit mounting bolts. Carefully slide the lower unit away from the outboard being careful not to damage the drive shaft or the shift shaft and youre done. So now that you have the lower unit removed on your Mercury Tracker 25.
Although being labeled the father of Mercury Outboards its interesting that Kiekhaefer actually worked as a draftsman for Evinrude outboard motors in 1927 however was fired after just 3 months employment with Evinrude. Kiekhaefer had 3 unique qualities that made him less than the ideal employee 1 He had a keen eye to see inherent flaws in mechanical designs 2 He often fixated and worked tirelessly trying.