How To Change Water Pump Mercury Outboard

Mark Corke has just recently posted about an outboard h2o pump service. Information technology is reproduced here on this web log, but I encourage you to go over to his web log site to read the whole story. Marker too has excellent blogs on other boating projects and topics of involvement to boaters. Well worth a click to read information technology at the source.

After Mark gives an introduction to the project at his blog site, the project is outlined below.

The engine that we serviced was a 1996 115 hp Mercury hung on the dorsum of a aluminum Starcraft of a similar vintage and the pictures refer to that but all outboards are very similar and although the pictures may not expect exactly like what you take the sequence volition be the same.

 I took the pictures as Adam Conte at Portside Marine in Danvers, MA serviced the pump. Working thoroughly and methodically he did the whole project in less than an hour so a competent possessor should exist able to practice the task from showtime to finish in under two hours.

 Here'due south how to do it.

The commencement step is to drain the oil from the gearbox. Unscrew the drain plug with a large screwdriver and the oil volition showtime to run out. Brand sure that you place a suitable pan under the motor to grab all the old oil. Unscrew the upper oil level plug besides which allows air into the gearbox and ensures that all the oil is evacuated. There are small washers under each screw caput which often get stuck in the threads, if they practice not come off with the screw you may have to pick them out with a pocket-size screwdriver or other tool. Permit the oil bleed as you motion onto the next footstep.

Loosen and remove the nuts that hold the lower unit of measurement in place, nearly all outboards have four nuts holding this in identify. A socket will not fit so employ a ring wrench to give good purchase on the nuts which will virtually certainly be stiff to undo.

 The lower unit should now theoretically be free but in practice it almost invariably sticks and volition need a few taps with a soft mallet. Do not hit the flange cavitation plates at the sides or they are sure to break, a few taps on the after end of the gearbox unit as shown hither are acceptable however.

 Once a cleft opens up the battle is won and y'all can insert a wide screwdriver and advisedly pry it apart being very careful not to impairment the castings of the mating surfaces.

 Elevator the unit clear and place it on a suitable bench or jig designed for belongings it. They service outboards everyday at Portside marine then had a proper jig on manus which is ideal but you lot may have to prop it upright in the corner of the garage, it works simply is just not as convenient and yous will be working at flooring level.

With the unit articulate of the top half of the outboard leg we can become to piece of work on the pump proper. The kickoff thing to do is to slide off the seal which sits atop the pump housing.

Unscrew the bolts that agree the pump housing in identify. We needed an impact wrench as this pump had not been serviced for some time but a ring wrench will work in nigh cases. Avoid using an open concluded wrench, if you round over the bolt heads you lot volition have a bad day for certain.

Separate the housing and slide information technology up the shaft. You lot can see in this picture that the bottom plate is coming off with information technology. We need to remove this plate also then if information technology stays stuck in place you may need to pry information technology upwards very carefully.

All in all the pump was in pretty skilful shape, all the vanes on the impeller are intact. Notation the one-time impeller on the right adjacent to the new 1 on the left. The vanes should exist straight, they develop a set to them after they have been in the pump for several months.

Before reinstalling the pump clean up all the mating surfaces to ensure that there volition exist no leaks. A sharp razor blade can be used to scrape off the larger bits of old gasket and sealant, then some fine emery paper volition get rid of the balance. Wipe down with some make clean rags when you are finished. Everything should be clean and vivid.

Clean out the interior of the pump housing checking to make sure that there are no score marks or gouges, if at that place are water may leak past the vanes of the impeller and the pump will non work as efficiently every bit it should. If in that location is any incertitude every bit to the condition of the housing so it should be replaced.

In addition to the impeller all the parts that are required for a routine service; gaskets, O rings and seals are included in the kit.

Subsequently cleaning up everything reassembly tin start. Smear on a little gasket cement. Adam swears by Permatex Course a Gasket sealant liquid merely whatsoever other proprietary brand should be fine.

Lower the gasket into position making sure all the holes line upward. The gasket is asymmetrical then if something looks wrong you may take it upside down.  Adjacent install the new lesser plate (shown) that comes in the pump kit, we used a trivial more than gasket cement before dropping this on.

Install the smaller gasket which seals the joint betwixt the top and bottom sections of the pump housing. This gasket has a neoprene bead built in so no cement is required or should exist used.

Install the new primal which sits in the flat on the shaft.

And then slide down the new impeller making sure that the key-way in the hub lines upward with the fundamental previously fitted.

A little glycerin or dish washing liquid makes getting the pump cover on that piddling fleck easier and provides some lubrication for the 2nd or ii until the h2o gets into the pump and lubricates the vanes. Do no use oil or silicone which tin assault the limerick of the impeller and lead to premature failure.

Slide the housing down and ease information technology over the vanes equally you twist the shaft in a clockwise direction with the other hand. This bends the blades and allows the body of the pump to sit fully downwardly onto the base of operations plate gasket.

Reinstall the bolts and tighten them till they are just snug.

Slide the new seal down over the shaft until information technology just rests against the pump housing.

A setting tool is included in the kit and this is pushed downward on top of the seal and does double duty of spreading it out and ensuring that it is not compressed too much. With the seal thus prepare the compression tool is then removed.

Smear a piffling engine spline coupling grease onto the top of the drive shaft.

And so a little more on the gear shift coupler which should even so be on the gear shift shaft inside the leg, it is a fairly loose push button fit so it may have fallen off onto the floor if information technology is not where it ought to exist.

Refill the gearbox with the correct oil. Note that reverse to what yous might expect the oil is forced in from the bottom until it comes out of the upper level hole, and then both screw plugs tin can be replaced with a new washer under each. Portside marine service lots of engine so that have a big tub of oil but the boilerplate DIY boater is more than like to use the oil that comes in squeezable quart bottles but the technique is exactly the same.

Reinstall the lower unit of measurement onto the leg, it helps a great deal to accept a helper rotate the engine by hand a little to get the splines to mesh. Then supervene upon the nuts and washers that hold the two parts together, there are torque settings for these simply Adam does them up and then they are just snug. As long as you don't swing on the wrench information technology is hard to over tighten these.

With everything back together the job is complete. We ran the engine in a butt to brand certain all was well. You can utilize muffs on the h2o pick up merely the force per unit area of the hose tends to strength the water into the engine, running it in a barrel ensures that the suck from the pump is right. Note that there should be a healthy spout of water coming out from the telltale in the engine housing.

Source: http://boatprojects.blogspot.com/2013/11/water-pump-impeller-replacement-on.html

Posted by: brownarand1988.blogspot.com

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