Replace Mercruiser Alpha outdrive water pump/impeller - DIY

[Music] hey what's up diy's mike bors with the mike boards channel thank you for watching we're working on our mercruiser outdrive and we are going to replace the impeller or water pump whatever you want to call it let's get started all right diy's outside of the outdrive engine this is a mercruiser alpha one gen one and the gen twos and bravos they're very similar so definitely stay tuned and what we always recommend prior to removing the out drive engine from your boat make sure you have a reliable stand to put it on to alleviate any damages to your engine and the stand in front of us holding that entire outdrive engine at the moment that was only about 150 dollars after tax and to the left of that is a small stand and that is going to hold the lower unit once we separate the upper unit from the lower unit and what we will do for your convenience is post those links down below in the comment section as well as description section on how to assemble those stands and get them ready to hold your out drive engine whether as a whole or in the event that you are separating them that black stand will hold the upper case and that white stand will hold the lower unit however let's get right into it we are going to replace the water pump and impeller and with that said coming to the back we are going to remove this little plastic cap and inside here is an allen bolt and let's go grab our allen wrenches and remove that internal bolt back from the toolbox and this requires a 3 8 size allen wrench and i'm definitely at a disadvantage having the engine removed from the boat on a stand with caster wheels but we're going to do our best and from here just go ahead and loosen that allen bolt and surprisingly that one very well as you loosen up that bolt your lower anode will come off and in the event that you plan on keeping it don't let it just drop on the floor and get damaged however you can see with the condition of ours we are going to be replacing that [Music] next thing we are going to remove is this 5 8 nut and after that you see this little washer and we'll have to grab a phillips screwdriver and remove that screw and that nut loosened off very easily and it's a good time to check that internal shaft in the event that you have oil running down that shaft your seals will definitely need to be replaced however back to this part phillips screwdriver remove that screw next real close to the nut we just removed on each side is a 5 8 nut and we need to loosen it up we're not going to be able to remove them fully until we get further along in this project but we need to loosen them up again grab a 5 8 wrench and as you do this just do your best not to scratch your paint to the opposite side quick update diyers that 5 8 allen bowl was very stubborn and i went ahead and sprayed it with some pb blaster and i'll show you what i did next here's the blaster i used and we will post a link down below in the comment section as well as description section on where to buy that grabbed a rubber mallet and with my left hand applied upward pressure where this hex key slides into the allen bolt and i used a rubber mallet to tap it and i did my best not to allow the hex key to touch the out drive itself to scratch the paint and just some friendly taps loosen it up i did allow 15 minutes for this pb blaster to work into that stubborn bowl after removing that bolt slide just in front of that and you will see two additional 5 8 nuts go ahead and remove both of those at this point diyers this is probably going to be the trickiest part of the project for me because i've got the engine off the boat and what we'll do now is just carefully tap with a rubber mallet until it separates as you can see here and as it separates just continue to loosen up those nuts until you can remove them and we'll hop to the opposite side do the same and we'll do our best to lower this lower unit into the towel and grass area without damaging that lower skeg and at that point we will shift it out and rest it down that white stand [Applause] at this point the upper unit is separated from the lower unit and surprisingly diys that went very smoothly and a couple things i've done is i put all the nuts back on the studs they came off of and put the bolts back where they came out of and down below two additional nuts and that little plastic cap and coming to the back side you'll see an oil passage and that feeds gear lube or oil from the lower unit up to the upper unit to feed lubrication to the top gears and diyers that's extremely important i also put a paper towel underneath the upper unit just in case there's any additional gear lube or oil it drips out onto the ground and from here what i might do is take that lower unit inside where we will continue the project all right the hours inside now at the craftsman workstation on the left-hand side on the stand you can see the upper unit we just finished up rebuilding that and again on the lower stand here is our lower unit and on top there is the water pump housing and inside there is the impeller at this point i've repositioned the lower unit and stand as shown here and diyers i am referencing my exact serial number service manual and following the exact disassembly or rebuild steps if yours is different i highly recommend following your specific service manual and with that said we'll start with this shaft here this is our drive shaft and you've got your prop shaft down below and right here are your splines and this little machine cutout is for a rubber o-ring and if you take your lower unit apart from your upper unit and you're missing an o-ring chances are it could be stuck in your vertical gear that is inside your upper unit and for your convenience here is our old vertical gear that came out of our upper unit during the rebuild process and that part right there feeds on right there that o-ring might be in there however what i recommend is just get a replacement o-ring they're probably less than two dollars from here i've got a couple sockets a one half a seven sixteenths and a five sixteenths to remove the nuts and hardware from the upper housing get a little closer and here is the half inch i will remove this half inch nut first and it should be very friendly to come off you should not have to really tug at it do your best not to drop these that would not be good and it looks like it is a nut and a washer carefully remove those and there it is from here let's remove the two 7 16 nuts and just like the half inch the two 7 16 nuts have washers go and remove both the nut and washer careful again try not to drop and lose them and to the back side to remove that second 7 16 nut and washer next the little 5 16 bolt careful as you maneuver the socket in place you may not be able to get a socket on it you may need to revert to a wrench due to the shape and clearance of the housing however be patient and careful with it do not strip it unless you're replacing this 5 16 bolt altogether and it's coming loose pretty easily and there is what that one looks like very unique from here we can carefully remove the water tube it should just pop right out and this acts as a guide set these aside next direct your attention to the upper portion of the water pump housing where it meets the bottom portion of the shaft and your setup may have a rubber o-ring or seal here if it does carefully shift it up the shaft and over the splines and off and from here we can carefully shift the upper water pump housing up just carefully rock it back and forth and it comes right up and off there's the inside and what i recommend is take a picture of the impeller and how it is positioned as far as the fins or blades we have to insert the new impeller the exact same way so it rotates properly for proper cooling of your engine after setting the top portion of the housing aside you've got this key on the lower portion of your shaft carefully remove that that's all it looks like do not drop it or lose it set that in a safe location after that we will carefully remove this upper gasket and you may need to use both hands to get it over the thread might get bound up but that came off pretty easily next you have a metal plate gasket you got these little tabs here you got to pull this up and over those tabs and rock it back and forth and up and off and when it comes time to reinstall that take note of that little indent right there and this little part right there that little notch or cutout that's circular that goes in that bottom portion there next the bottom gasket and if you rip these no worries because you should get replacement gaskets in your kit and at this point diyers we have now gained access to the lower base of the water pump housing in most cases when you are doing an impeller replacement you do not replace the lower base of the housing however if you buy a full replacement kit it will come with a base so with that said for your convenience we are going to continue and remove that base coming to the back side and what we need to do is separate the lower base from the gasket down below a couple ways to do this after i have some cardboard here and the last thing you want to do is scratch or dent any portion of your lower unit case or shell and right here i'm going to carefully position those pieces of cardboard i've got a long craftsman flathead i will place the screw tip underneath the portion of the base that the long 5 16th screw or bolt goes into and i'll just carefully tap it and separate that base from the lower gasket looks like we've made progress from here i just got some pliers and i'll carefully continue rocking that base back and forth and pulling up on that base to pull it up and off the shaft i may need both hands and as you just saw this base was holding on for dear life however those pliers came in very handy just shift the base up and off and set that aside and we will carefully remove the lower gasket gets caught up on the thread and from here we are going to continue the full disassemble and rebuild of this lower unit however we are not going to bore you with that in this video in the event that you want step-by-step guidance on how to continue the full rebuild definitely check out the link scrolling above it will pick up right where we left off which is shifting down below to the prop shaft to remove the prop shaft bearing carrier and all of the internal gears however if you're not rebuilding we'll do all that and then we'll be right back with you back with you diys and at this point we have rebuilt the entire inner portion of our lower case from the bearing carrier oil seals gears shift shaft crank drive shaft and that was fun here is the base for our water pump there's the part number and here is the water pump upper repair kit let's go and open everything here it is all unpackaged and again left side there's the base the o-ring the impeller a couple gaskets there's the water pump housing a new key the tube and a few additional rubber seals as well as the screw i'll reposition the camera let's get started at this point i've removed the blue tie strap that secured the lower unit to the base i've grabbed the quick silver marine grease 24c with teflon and that is what the ptfe stands for the service manual calls for this specific grease during this stage of the project the base of our water pump we are going to first install the gasket and by doing that make sure you line it up properly as shown here and you want to put the gasket on before you put the o-ring on because once you put the o-ring on it's going to be tough to get that gasket on what we'll do now is lubricate this o-ring and you're going to get a little dirty but that's okay this grease will help the o-ring shift onto that base a lot more efficiently and it will assist in creating that watertight or oil tight seal i'm gonna drive my hands real quick and basically grabbing one end of the base with my thumb and install this o-ring as shown here right in that little gap what i'll do from here is lubricate the outer edge of the base itself as well as just a little bit inside where the seal is do your best not to get sloppy with it and again just a little bit on the inside of that oil seal just like that next i reposition the lower unit and stand back onto the ground to give you a better view of this grab your base ensure that your gasket and o-ring are properly placed and we'll slide it down the drive shaft keep the gasket flush with the bottom portion of the base as you slide this down and align it with the threaded studs and as you shift this down properly align that bottom portion and give it some friendly pressure to properly seat it inside the cavity as shown here and you will know it's properly seated when it is actually below the surface of the lower unit case now it's time to install the gaskets the first gasket we will install is this one right here diy-ers it is extremely important to install these gaskets in the proper order or when it comes time to pressure test you won't actually be able to hold pressure slide these down the threaded studs do your best not to rip them and the top portion of the base has these two black tabs properly align the gasket holes with those tabs and push it flush with the base next your face plate as shown here same thing it's got two holes for those two tabs as shown here in the final gasket this one right here same thing align the tabs with the holes and push the gasket flush with the top portion of the faceplate now it's time to install the key i'm going to turn the drive shaft you can see the machine cut out for the key and the back side of the key what i did was apply just some grease and this is going to help it stick to the actual shaft as shown here i'll zoom in there it is and i am going to shift the drive shaft back so that the key is perfectly aligned and facing the rear portion of the lower unit back to the workstation and again here is the brand new water pump housing here is the new impeller and a couple additional parts here is my old housing and i am going to reference when i install that impeller into the housing the actual impeller blades or fins or veins whatever you want to call them are positioned the proper way so i'll set that aside and to do that we basically have to grab the housing with our left hand impeller with the right hand and shift the entire impeller counterclockwise but i'm going to lubricate the inner portion of this housing first with teflon and this portion again don't overdo it you just need a light coat of grease on the inner portion of this housing and that's going to assist in getting this impeller in from here i'll just add some friendly pressure as i do this and it's not easy and there it is it is in and from here what i want to do is align that little groove inside the inner housing with that little gap inside that will line up right there with the number two and it is basically in line and flush i'll give it one last good push down to make sure the entire rubber impeller is properly seated in that housing and a quick reference to the old one just to ensure they're the same if you install this incorrectly you're going to overheat your engine that is not what you want and what i will do next is lubricate the inner seal that the water tube is going to seat up against and install the water tube and that is it i'm just cleaning some marks off the water tube set that aside next thing i'm going to do is just lubricate the inner seal or top portion of the impeller inside again don't overdo it next time to install the impeller and as you do this what we did was properly align the internal impeller so that the groove will line up with the key and if you do this correctly it should go on very easily as shown here now it's time to install the hardware i've got the half inch nut and washer and i'm going to hand tighten this only next your 7 16 washer and nut again hand tighten only do not cross thread these nuts onto the threaded studs that would not be good and now to the front side last but not least your 5 16 screw back to the ratchet and socket we are going to tighten all of the hardware in sequence and what i mean by that is we will start here and tighten this five to seven turns come to this nut five to seven turns five to seven turns five to seven turns and by doing that in sequence it will properly seat this housing to the gasket to create that watertight seal at this point i've got all three nuts secured and the 5 16 screw and i've grabbed the gasket here i lubricated the inside of it and just shift this all the way down flush with the top portion of the water pump housing next i grabbed the o-ring and i lubricated that with that 2 4-c grease and same thing shift it over the spline portion and it will shift right into the machine groove on the shaft back on top of the workstation i am now going to carefully remove the rubber oil feed gasket just have a little pick tool here and it comes right out as you see here and a little stubborn in that area there it is i am now going to clean the inner portion next i grab the new oil seal and i just dabbed a little bit of sae 90 gear lou and i'm going to lubricate the gasket as shown here and i'm going to properly seat it inside the little groove or cut out and just apply some friendly pressure and clean up the top portion as shown there to a different camera angle here is the finished product as you can see and our specific service manual called for those nuts to be tightened to 70 inch pounds not foot pounds inch pounds and that 5 16 screw to 30 inch pounds so reference your owner's manual to ensure you're not over tightening the water pump housing in place what we'll do now is shift down and replace the water pickup inserts you got one on each side we'll need a phillips screwdriver from here we got to do a pressure test scrolling above right now is the link to that video definitely check it out from here we hope you're still with us again thanks for watching do us a favor below the video you will see that thumbs up icon click on that like the video subscribe to the channel definitely ring your youtube bell that would be very helpful to us we'd really appreciate it thanks again for watching [Music] you

Channel: DIY with Michael Borders

Views: 29,477

Keywords: boat battery dying, replace water pump, replace boat impeller, DIY token, Toolbox token, mercruiser rebuild, upper unit rebuild, lower unit rebuild, BTC, ETH coin

Id: CHVKPIU7Z9o

Length: 22min 2sec (1322 seconds)

Published: Tue Jul 05 2022