How to Replace the Water Pump Impeller on a 40HP Mercury Outboard motor.
In this video on our annual service of a 40 hp mercury Four stroke outboard motor I go through all the steps involved in replacing the water pump impeller. Including removing the Lower unit, inspecting and replacing the impeller. I also give a demonstration and description of how an outboard motor water pump actually pumps water. I show you how to install the lower unit and how to identify what gear the lower unit is in. I show you how to get the splines to line up so the lower unit is easier to install. They can be very difficult sometimes.
0:00 How to remove the propeller and Lower Unit
5:45 How to Inspect & Replace the Water Pump Impeller
10:07 Description of Water Pump Operation
17:02 Installing the New Impeller
27:16 Description of the Shift Shaft Operation
29:00 How to Install the Lower Unit.
Пікірлер: 81
You are THE ONLY person aside from my father that I have ever heard mention “shocking” a bolt with a punch. My grandfather had a stuck bolt on a big piece of farm equipment. He leaned into it with a big wrench and when my dad shocked it, my grandfather fell down. Thanks for the fantastic video!
Glad I came across your video - nicely done! I have seen a couple other videos on the subject impeller replacement, however, yours is by far the absolute best. Simple but sufficient detail. I will use it to guide me through the process on my new to me 2018 40 hp 4 stroke motor. Thank you sir!
This is probably the best instructional video I have ever seen. Thank you for sharing your knowledge!
@neo2high
7 ай бұрын
THIS! The best instructional video I have ever seen!
Awesome video!! Thanks so much!! Very professional...step by step....so helpful!!
This vid is saved for when I get the time and nerve up to replace the impeller on my own. Thanx.
Can't say again how much I love your videos!
Thanks for this great video and i tested my 90 HP Mercury and my pump is out. I am use to working on my car, my LT1 trans am. So now I know how to handle the water pump.
great job and in-depth even I think I can do it now. thank you!
Great video.
Did mine went back together perfect, thanks so much!!!!
Life saving video Thank you for both showing and explaining the way you are/do Really like your videos Keep it up
Just ran across this, this is a great and informative video
best video on this i’ve found, thank you sir!
Nice tips and great explanation of all. Thank you
Very nice video! Very instructional and the reference to why not to use impact wrenches on sensitive or bolts which may be corroded. Thanks!
@CanadaWideMarine
Жыл бұрын
I don't use impact wrenches very often, they strip threads and break bolts. When I do use an impact driver I loosen or start the bolts by hand to ensure the threads are free before running them up with the impact driver. The only time I ever break a bolt off and have to drill it out is when there is absolutely no other option, which is very rare, in fact I don't remember the last time I had to drill a broken bolt out.
That was spot on. Thank you sir.
That’s for all the information!
What kind of clamp/vise is that supporting the lower unit? I am trying to find something similar to that for my own workstation. thank you! Your video is excellent.
Hi there, enjoy your videos on the marine service, I am having an issue with the Mercury 40HP 4 stroke, I only had it for a couple of years, and bought it used, It ran ok for the first year, then one time the overheating, went away. then this has been quite frequent, I replaced all the water pump parts, thought was the problem as there was a significant amount of water being discharged. First run-out last week same thing but it seemed to get hotter more quickly. Removed the thermostat, tested on the stove by gently heating up the water, and opened it up at 180, did the test a few times leaving it to cool but found the thermostat to be somewhat sticking. The spark plugs look great fuel burn is excellent. should I try a new thermostat or do you think it could be a head gasket issue. The compression test on all cylinders is within spec, appreciate your input.
At what point do you know when to remove , lower plate that sits under impeller be it to replace the plate or maybe inspect what’s below ? Only if water gets in gear oil ? Possibly and how thick are those washers that sit on either side of the impeller mine look wafer thin , your vid is very informative thankyou
Thank you for sharing your skills, could you tell me is the 30hp,four stroke the same set up as that 40 hp. motor . i am about to do mine. thank you. Aussie Chris
Awesome
just curious, you use grease on the bolts, but wouldn't anti seize work better. Great vid by the way
Hi! I followed your instructions for this, and afterwards my gear selector / throttle is very sluggish and requires some force to go forward/backward. I think i might have done something wrong with the gear selector in the shift shaft operator. Do you have any insight for this? The engine runs well, and goes forward/backward. Its only the throttle thats sluggish. Thanks for this video!
Is there a torque setting for the large bolts and the impeller housing
@jeepza889
4 ай бұрын
40 ft/lbs on the large bolts. 60 in/lbs on impeller housing.
I have a 1999 mariner 50hp with a constant high pitched alarm, suggesting overheating.. any chance you could do a video on these things and what to do about it? Thank you 😊
I will never complain about what it costs to do this maintenance again.
hi ,,, good video.. I have a 60 hp merc 2014 on my boat it doesnt have a seal face on top of the impeller housing. i noticed yours didnt have one either. Do some motors not have this seal...
The sealing ring that you almost forgot- would it be detrimental if you did? I pinched mine with the key a little bit. It’s not torn, just not perfect like it used to be. Do you think it matters if the sealing rings are exactly perfect ?
Great video thank you! Your Volvo Penta videos seem to get the most views. I sent you a message on the website, I’d be happy to bring my boat with twin VP 4.3gxi sx drive engines for full service with you, even if you are about 5 hours from my home port. You can use it for filming more VP content:)
@CanadaWideMarine
Жыл бұрын
That is very flattering. I'll have a look for your message. Where is your home port?
@smileoftenatsea
Жыл бұрын
@@CanadaWideMarine Maple Bay on Vancouver Island
Did you rotate the pump housing CCW and the shaft CW to install the impeller?
Out in Howard before you remove the lower unit.
Gday mate you do a good thorough job id be happy to let you work on my engine ,i have to say that leg and even inside the propellor looked a bit nasty is it corrosion or calcium build up either way didnt look good , never to much grease except on the top of the shaft especially in salt water ,we dont get much sierra gear here i think you can get it but you have to find a retailer and frieght from the U.S to A.U is a killer wanted to but some spare mounting bolts for my yamaha frieght was around 60 dollars for 4 bolts anyway good video .
@CanadaWideMarine
Жыл бұрын
Yes. That was an old motor, we don't generally work on stuff that old. Hit us up next time you want Sierra parts, or any parts that are hard to get down there, we have shipped to Australia before. As a side note I spent 17 years in Australia, up until 2000. East Coast mostly, Brisbane to Sydney, and Hunter Valley.
@crispernator
Жыл бұрын
@@CanadaWideMarine Hi mate briso i could handle spent a bit of time in townsville courtesy of her majestys armed forces sydney naa not for me and the hunter valley spent some time there too at the infantry centre singleton on and off , i have a mate who has a 1975 johnston 35 and he cannot get any mech to touch it he asked me and i declined sure as eggs a bolt will snap somewhere and i aint paying for a new engine
I have a 2012 mercury 40hp 4 stroke. After I changed my impeller I hear a squeaky or whistling noise coming from the motor at low rpm’s. Sometimes I can give it a little throttle and it goes away. Other times it’s pretty steady at idle or low rpm’s. Some people are telling me to rub more grease on the shaft because the shaft runs through a bushing and that’s were the noise is coming from. Does this sound right to you? Thanks for any help you might have with this.
@CanadaWideMarine
Жыл бұрын
Many outboards have a bushing on the driveshaft to reduce flex. Often I see corrosion buildup around the bushing that tightens it up against the shaft. If that is the case I replace the bushing and clean up the corrosion. A little grease may help, but it is lubricated by water from the pump, so if it is noisy it is probably too tight.
Im pretty sure my water pump went out after sitting, as i finally got the condensation out of the fuel system and got it started but not spitting water. Made sure the lines weren't clogged and no water is pumping 😫. Im hoping i can tackle this myself as i am decently mechanically inclined. Thanks for the detailed video!
Hi, I have a 2012 Mercury 60 hp, My question is, does the low pressure fuel filter be full of fuel all the time? I notice that it is almost empty while running.
@CanadaWideMarine
Жыл бұрын
Yes, and no. If the filter is positioned so the air can bleed out of it then in a perfect world there should be no air in it. most of the time the filter does not bleed the air out, so air remains in the housing, add the vacuum of the low pressure pump and it will expand the volume of air. Now, we also need to be sure that we are not pulling an unnecessary amount of vacuum because of a restriction in the supply side, and we also want to be sure there are no possibilities of air leaks into the supply side adding air to the system.
The Sierra 18-3324 Water Pump Kit below is recommended for your outboard 40 hp Mercury 2 stroke. The kit model #WATER PUMP KIT 77177A3 your Mercury 40 hp is a little different than mine as I only have two bolts that hold the bottom end on. Does that make mine older or newer than the one your working on?
@CanadaWideMarine
Жыл бұрын
I'm sorry, I don't know the answer to that. We don't work on very many old outboards so I am not familiar with the year model changes and such. If you go to public-mercurymarine.sysonline.com/Default.aspx?sysname=NorthAmerica&company=Guest&NA_KEY=NA_KEY_VALUE&langIF=eng&langDB=eng and punch in your serial number it might help you identify a year model.
@CDavid1951
Жыл бұрын
@@CanadaWideMarine I found a 1996 model that only had three studs running through to hold the prop end on. I have done most of the work I am just trying to get both tyranny shaft back in and the ? water tube in it's place. The salmon are just starting to run up the Columbia river and the Willamette river it's time to get out on the water. 5/12/2023
My dads been using the same one for 20 years before it went.
Would you happen to know if it’s safe to use Lucas multi purpose Maine grease for this? It’s the grease I use in my wheel bearings.
@CanadaWideMarine
Жыл бұрын
I use the Lucas Marine grease for everything except lubricating rubber parts like the impeller. For the impeller you can use dish soap, or a silicone grease.
@ntj030885
Жыл бұрын
@@CanadaWideMarine awesome. Thanks for the help. I’m getting ready to do this for the first time in a few weeks.
@codymitchell7051
Жыл бұрын
Watched your video about 3 times I am a 75 years old and a woman if I can do it any one can you are a very good teacher for this video . I would like to see more. Thank you!!
@tightline6lb
Жыл бұрын
Just one question if u took the lower unit off while it was in neutral, why can't u just put the lower unit back on in neutral, why do u have to put it in forward?
@CanadaWideMarine
Жыл бұрын
@@tightline6lb I put it in gear so I can turn the propeller to turn the driveshaft to line up the splines.
Should the engine be in nuetral or in gear when doing this service?
@CanadaWideMarine
Жыл бұрын
I generally do it in neutral. But sometimes I need to put both the drive and the control in fwd gear during assembly so I can turn the prop shaft to align the splines on the driveshaft.
Is the impeller procedure basically the same for a 2018 60 hp EFI 4 stroke ?
@CanadaWideMarine
Жыл бұрын
yes, basically the same procedure for all outboards really.
@BennyLandron60
Жыл бұрын
@@CanadaWideMarine Thank you very much for the reply and video.
I need to change the water pump on my Honda 40hp outboard. Is it the same procedure? Any help, advice, links to help would be greatly appreciated. Thank you!
@CanadaWideMarine
Жыл бұрын
pretty much the exact same procedure, except for the shift shaft connection which is a little different.
@GallagherRC
Жыл бұрын
@@CanadaWideMarine do I have to align anything or make sure anything is done in particular way when I undo it? Can I do everything with the boat in neutral?
@CanadaWideMarine
Жыл бұрын
The Honda shift linkage is usually connected with a threaded adapter between the upper and lower shift shaft. It shifts by pushing and pulling the shaft up and down. I find it easiest to put the control in reverse, this lowers the threaded adapter, loosen the jam nut, and screw the adapter all the way up onto the upper shaft. then remove the lower unit as normal. When installing, be sure the lower unit and control are both in reverse, install the drive and tighten it all the way BEFORE re-connecting the threaded adapter to the lower shift shaft. this ensures that the relationship between the upper and lower shift shafts is correct. I may have done a video on this type of shift linkage, I just don't remember which one it is, you'll just have to watch them all. ;)
@GallagherRC
Жыл бұрын
@@CanadaWideMarine Thank you! I’ll check out you videos to see if you made one like my situation.
Will this be the same on a 2012 mercury 40hp 4stroke?
@CanadaWideMarine
Жыл бұрын
Pretty much. The process to service the impeller is similar on all outboards.
Tell me about the bent vise
@CanadaWideMarine
Жыл бұрын
AH yes, that is a favorite whenever anyone visits my shop. I spent many years in Australia, and the offset vice is pretty standard down there, so I brought this one back with me.
È necessario togliere l’elica?
@CanadaWideMarine
Жыл бұрын
not really, but you should grease the propeller shaft splines every year.
Reparación de la transmisión del 40 y50 hp 2 t
Do I have to remove my propeller to replace the impeller on my 40 mercury 4 stroke?
Why not just put everything in forward before you take the lower unit off?
@CanadaWideMarine
Жыл бұрын
To be totally honest, the main reason is because I always forget on these ones. Most of the motors I work on are fine splines, that don't need much to align them, so these older Mercs with coarse splines. The other reason is I often do other work on the lower unit and loose track of what gear it is in, so I like to be sure when it is going back together.
@Steve_Balboni
Жыл бұрын
@@CanadaWideMarine thanks. Awesome video!
Gday jim i have just finished watching a guy called boat crappies do a service on the lower leg of a 40hp yamaha and yes he lives up to his youtube name ,there was not a sceric of grease used at all on any part ,impellor housing ,bolts ,driveshaft splines and he didn:t even take of the prop to check for fishing line or grease the splines .Now im no marine mech by any length but it makes me angry when i see people putting up you tube videos where some other guy is going to think this person is the bee knees and follow what he has done i recomend your site to people when i think or they have a certain problem with there yamaha such as changing the fuel filter on a f50 i told the guy to check out the maintenance you did on the yam f 50 ,grease is your friend it can save you money ,it can save you time and most of all it can save you heartache when the mech tell you your engine is stuffed my saying is GREASE IS YOUR FRIEND i let this person know that he should have done this when reasembling but it will probably go over his head bloody yanks .