2 stroke mercury 25hp installing a new outboard water pump, impeller and coldstart

replacing an outboard water pump and impeller on a 1998 mercury 25hp 2 stroke outboard engine.
USA
pump kit (OEM) seen in this video
amzn.to/2teSs3p
or
amzn.to/2sJH5is
Canada
amzn.to/2sZ1sqJ

[@sparlin88]

I want to thank you for helping me solve a problem. I just bought my first outboard . A 1999 25hp mercury . Bought from a guy about 100 miles away . Went there and it fired right up and ran smooth . Paid him $1,200 and took it home . Put it on this boat I just bought also and started it up with no problems . Went to put it in gear and didn't go in forward or reverse. I called the guy complaining and was told its my problem basically. So got here on youtube and found your post on changing water pump so went out and found out his great mechanic he bragged about didn't put the locking pin back on the gear selector shaft . Its fixed now and my wife is son happy . We both believed we were ripped off by a guy with no conscience or heart . Just greed. Thanks so VERY MUCH !!!!! YOU ROCK !!!

[@521VX05]

Excellent video. Was a great help in getting our 2000 25 EH changed out this week. Only difficulty we had was the shifter wanting to change gears as we fed it up the tube when reinstalling the lower. Just took some trial and error.

[@partsbenttoys]

6 yr old vid, still useful and helping ppl get by. thank you, great video btw

[@channel-gj8pl]

Thanks for the information on You Tube. I changed a water pump for a friend today and it went just as you showed. This improved my chance of having a successful repair. The engine was a 1991 Merc 25.

[@t.d.mich.7064]

Thanks for the heads up about the shift linkage disconnect! I've done this job before on smaller Mercs without electric start, I would not have known to look for this before trying to drop the lower unit. Good info!

[@johnvyverberg3283]

Thanks for the tip on removing the clip for the shift linkage! I was puzzled by this until I saw the video. BTW, my engine is a 9.9 Belgian 2 stroke.

[@aaronm1375]

Thank you, excellent video. My nephews dry started my Mercury 25 when I wasn't around, and it was recommended I replace the impeller before taking it out on the water again. I was dreading it, but after watching this video I am confident I can handle it. And I was gracious to my nephews since they didn't know how bad dry starting is, but they do have strict instructions on what will happen if they ever dry start it again. Thank goodness one of them tattled to me, or I might have never known.

[@John-of5sh]

Excellent video-Definitely on my "To-Do" list. Thanks so much for sharing your time and expertise!

[@alexmillwood1433]

Thanks heaps mate I've just bought one of these after watching this I feel confident to do the job myself and learn a lot more about these great little motors cheers for saving me some cash to every little bit helps at the moment

[@darrylhenchie4765]

A brilliant tutorial. Thanks mate. Just purchased a dinghy with 99 Mercury 25 hp. You're video was a brilliant and timely find. I've subscribed😁

[@JBOutdoors]

Thanks for a great walk through video. I've done a smaller 7.5 hp mercury and wanted to compare as I'm doing one on a similar motor to yours.

[@deanbowe4070]

Just used your video to change the impeller on my mariner motor, thanks!

[@ericbrown9835]

Excellent video. I'm not at all hesitant to now take on my impeller change out.

[@laloromero6860]

I paid someone like $200 because I thought it was going to be way to hard for to work on the lower unit. Your video makes it possible thanks!

[@fredrikh9299]

Thank you for generously sharing your know-how and taking the time to make a very instructive video! Regards from Sweden.

[@TheRfleming]

You were very informative and you didn't talk to much.Thank you.

[@kevinapel3027]

Best video for this subject I have seen. Thanks for helping me out! You missed your calling. You should make instructional videos for other things. Thanks again

[@ShnitzlHaus]

+Kevin Apel thanks Kevin :). I do what I can, but have to work a job that pays the bills to. Life :)

[@classicbikerx3588]

Wow, so much harder than the bigger units due to shift linkage! Good vid

[@bart2u]

I had no ideal where the release was for shifting linkage. Thankyou so much for making this vidio. The macanic wanted 1 and1/2 hour and up to $100 dollars for parts u saved me $400

[@JesusLove723]

I have a 2000 25hp mercury... This vid was a great help. Thx!!

[@jameswhitman2240]

Thank you for the very helpful video. Can you offer some additional guidance and some trouble shooting. I replaced the impeller on my 4 stroke Mercury 30HP of similar vintage to the motor you work on during video and followed the steps carefully. After I got the engine put back together with the new impeller and restarted the engine, it doesn't make water fully. There is just a bit of water coming out of the outflow and it looks like water is being pushed up from the lower unit but outside of the lower housing. It appears as though only some of the water is making it to the upper section. Where would you start to diagnose where I may have made a mistake?Thanks

[@robertcook1065]

after watching your video a bunch of times I did replace water pump today and cured the problem. thanks

[@georges947]

Thanks for the reply I'm thinking is good looks the same at the end of video it's been sitting since 2005 just picked it up and going though it. Thanks.

[@williammadden9558]

I cant say thank you enough! I have a 1989 MERCURY 25 HP outboard. One place wanted $350 and others didn't even return calls for this job. $46 for the kit on Amazon. Your video was excellent. You cover everything extremely well. Only difference on the 1989 engine is the carb cover and starter are on the port side of the engine. I only had 1 issue getting the o ring to stay on the housing cover. I had to stretch it a bit, which took some doing, so it didnt want to roll off. Once again, excellent video and a sincere thank you!

[@freddynews6478]

Excellent video and description narrative.

[@williamdabinett6222]

Thank you so much I’m so happy you done such a clear video Just wound Fil I’m from Australia thanks mate 🙏

[@tandk86]

Great work! Mine is flowing water like I never seen with pressure

[@bobg69]

Is that retainer pin on the shifting linkage also on the 94 model? Might be doing this same project this spring. Also, do you notice water coming out from the lower unit and exhaust housing mating seem? I noticed mine is just a slight amount. Not sure if that is normal there is a seal leaking somewhere?

[@jackgunter3999]

Your video just saved my day!!! Thank you

[@bryantoney3275]

Nice video!! Any idea what the other o-rings are for in the kit?

[@captlarry-3525]

thanks ! my 20's are older with a screw holding the shift rod,, but I am sure the hints still apply, I am now a whole LOT more likely to do this important maint job !

[@russwentz3957]

Thank you, thank you, thank you! Between diagrams and service manual, wasn't clear on the shift linkage. Very clear, well done video. Thank you for your time to pass it on.

[@ksemi02]

Very informative, I’m doing mine now. But my kit came with two the paper gaskets, did yours? Thanks:)

[@DougLandry-ub4dg]

Thank you just did mine . Your video was a great help.

[@davidv7616]

Great detailed step by step thank you I just did mine today

[@MrGabys91]

My water tube stayed inside, it didn't come off. The water tube seal (the rubber piece you referred to) stayed attached to the housing though. I have a 94 merc 25 hp 2 stroke. I didnt hear anything crack, everything came out smooth. Is mine just like that?

[@chuckburgess6592]

looks like my job next. thanks for the information.

[@tomschwartz2811]

The water tube came out when I dropped the lower end. With it going so far up in the motor, it's not that easy to re-insert it. I took a 5/16" wooden dowel and put it into the lower tube end. It's a tight fit and makes it a lot easier to re-insert the tube. The straight end of the tube goes up.

[@cagleoutdoors6384]

This video saved me a ton of time thankyou your a life saver

[@RubiconUnlimited]

this install is Water Tight! great vid

[@MrAndreisousa]

hi thanks so much for this video, if I do everything correctly and still no water coming out in that same spot, that means there is a blockage somewhere, any ideas how to fixed it? thanks in advance

[@Streetfords93]

Hey just want to know what the linkage (The one that connects to the plastic piece on the side of the carby) you have taken off as Im missing it on mine and want to know what it does as mine works fine without that linkage? Thanks!

[@markbaldwin975]

Great video...very thorough and detailed.

[@ShnitzlHaus]

+Mark Baldwin :).

[@jimfry5385]

nice video. one question. I saw that you didn't use the 4-bushings. how come? Thanks Jim

[@dylandavis4074]

Do these 25hp models have a thermostat or should they be pumping water immediately when running?

[@oilheating214]

Wow you make it look easy

[@MichaelPop72]

Hello, is the process the same on a 2006 four stroke with same hp?

[@samlancaster6767]

What is the hole in the lower unit just above the water line that’s shooting out water? I just replaced my water pump and noticed mine was doing that.

[@Asys1985]

I changed impellar and mine is leaking water out from the area just above the water level. Alittle bit above the lower stream you have. Any idea what it can be? I get a stream up aswell and its alittle hot so you can atleast touch it without getting burned.

[@jonathanb9429]

Excellent video ! Thanks

[@ajfarr3369]

Should the water tube on my 2003 mercury 25 HP have a snug seal at the top end ? There is a lot of space at the top around the tube .

[@georges947]

Your video is great ! The manual said nothing about removing that upper pin anyway water does come out but after about 2 minutes very hot ! Any idea what to do or is that normal? I'm new to these motors.

[@ShnitzlHaus]

It should be coming out as a strong stream when the thermostat opens, spitting to light stream when closed. Hard to say on temp as it should be hot. If you are in salt water you might have corrosion and build up in the water passages.

[@papazoo1]

Nice detailed video, I just bought a boat with a 97 mercury 25 HP, and was concerned that I may have a bad water pump because it didn't have a good steady flow of water. It will go between a good steady stream to sputtering out just a small amount. I notice yours look the same, is this normal. I haven't put in water yet just using muffs. I was told it was service with new impeller, but was thinking about putting a new one in to be on the safe side.

[@ShnitzlHaus]

If you have a thermostat that will be a reason for the sputtering stream. I haven’t had allot of success with muffs as of now. Try a garbage can full of water, rev the engine slightly out of gear. It should warm up enough to make a constant stream. I doubt your impeller is shot, but it’s good to be cautious.

[@papazoo1]

Thanks you for responding, that as fast. That makes sense about the thermostat will try the container method also. Look Forward to viewing your other videos.

[@ct1762]

that shift rod clip is a bit easier than my 82' 18 merc.. ingenious design. you do want to slap some 2 stroke oil inside the pump housing and on the baseplate, however.

[@larryhauck3285]

Fantastic video!

[@user-mx8gy7gl5g]

Hey dude loved the video great help I’m not much of a mechanic. But I do have a problem hopefully you can get back to me. Put everything back I believe correctly except I do not have forward on my motor what did I do wrong?

[@ZoutdoorZ]

What is that bolt on the bottom on the lower unit by the hydrofoil ? You can see it at 7:20

[@viviendolavidafeliz]

Thanks for your video, I'm trying to get the extractor key for the tail of that same engine and I can't find it anywhere and many mechanics don't even have that key. Can you help me know where I can get that key?

[@tbtactical]

I have gas dripping down from between the prop and skeg. Any idea what's going on? Boat will turn over but won't continue running. Also, great video! Thank you!

[@ShnitzlHaus]

Exhaust runs past the inner prop. Normal. If allot of raw fuel it’s rich. If just oil normal. Hard to tell without seeing.

[@socalinhouse]

Nice job dude.

[@goneFishing-yx5zy]

I just did one today and notice water coming out of where the shift rod comes through the that gap right about the lower unit dose yours do the same

[@ericremillard8335]

What is the point of the little washer on the shifter part? I changed mine but it didn't have 1. I bought it used tho so the owners before me might of lost it ?

[@Dave-jc6ky]

My motor is a 1987 Mercury 2 stroke and requires an o-ring seal near the end of the driveshaft. It wasn't on mine and I'm wondering if it came off during removal of lower unit and remains inside of the driveshaft housing. Do you happen to know how to remove the driveshaft housing so I can check for the o-ring?

[@shaneodom6574]

Just curious I lost the washer on the shift linkage. Should I go-to my dealer and try to figure out what size? Or can run with out it? Oh I have a 1988 25 horse mercury. Not even sure if it came with one

[@huntmasterjames]

Do those reed valves got bad. I been having trouble keeping my 25 hp mercury running. Carb rebuilt. Replaced vacuum lines.. getting gas out of vacuum lines when suction applied. Any suggestions.

[@thomasblais7751]

Hey man do u bolt on the motor to your transom?

[@TheMentiply33]

Nice work got to do mine

[@stevejones6111]

Great Video. I would suggest putting a little light grease around the vanes on the wear plate and the top of the impeller housing so you have lubrication on first start up before the water reaches the impeller.

[@ShnitzlHaus]

Agree. I believe I used petroleum jelly in the video. Anything works.

[@dylandavis4074]

@@ShnitzlHaus isn't petroleum jelly, or any petroleum based grease not good to use on rubber parts? Causes them to swell? This is what I've learned with brake parts on vehicles? I use Syl-Glide for rubber brake parts. I've seen petroleum based grease degrade caliper slid pin boots and caliper seal. Great video though, I'm about to do this with an outboard I just bought.

[@ShnitzlHaus]

Yes you are correct but realistically it’s going to get washed out fast and argumentative points would be the impeller is a wear item and needs to be replaced regardless. Also most of these impellers are likely seeing many dry starts from sitting in storage to pulling the boat out of water for lengths of time.

[@Ethan-tz4kp]

Does anyone know about how long this would take for someone whose never done it before with decent mechanic skills? Thanks, the video is awesome and giving me the confidence to maybe try myself!

[@jeffreyotten7020]

2 hours from start to finish. Did it yesterday.

[@randallwharrell]

Great video. At 3:36 you talk about that washer. What is the function of that washer? Also, when I dropped my lower unit, the drive rod and spline rod came all the way out. But the other rod (I’m thinking it’s a pipe that uses water for cooling. Should it come out when removing the lower unit?

[@ShnitzlHaus]

I can’t recall the washer. If it supported the rubber when shifting on the upper head side (engine). If the pipe doesn’t come out that’s okay. When assembling it’s better to have the pipe in first because it’s near impossible to tell where it’s going when it’s installed on the pump first. And if it doesn’t engage the engine above you will not have cooling and will need to drop the lower unit again.

[@tonyfarr7397]

The washer fell out when you re o ed the lower u it ! Look for it on your video

[@gardeningGTA]

I have the same motor but with electric start. I can start the engine. But the engine bogs out and stalls after I press the accelerator. Any tips , ideas what the issue might be ?

[@Dave-jc6ky]

HI, Our 25 hp 2 stroke is a 1987. It look similar in design though the part to disconnect shift shaft is a bit different. I understand on mine there is supposed to a washer on the shift shaft to you have to be careful not to lose when dropping the lower unit. Is there something that insures on yours the washer doesn't fall off inside the motor when you drop the lower unit?

[@connorjacob4339]

I think I lost mine and I haven't put it back together yet do you know what it's for

[@TheRfleming]

Mine is a 72 20hp is there a lot of defferents?

[@hc243102]

was that blue thread locker that you used on the pump housing bolts?

[@ShnitzlHaus]

Tend to use blue on everything. Good sealant also helps to stop oxidation.

[@socalinhouse]

excellent video dude!

[@ShnitzlHaus]

Thanks!

[@shanehester4852]

Do you know if these motors have a temperature alarm or not I have a 1998

[@therzayyy7345]

Is replacing the starter just that easy? I know it’s about the impeller but I have to replace both the starter and water pump on mine

[@ShnitzlHaus]

Yes. Disconnect the wires and two bolts that hold the starter on.

[@enercaledonie8496]

Merci pour le partage de nouvelle caledonie 😉👍

[@JulietteNiner]

you know what that shift clip is called or where to get it? Cant believe mine broke. Thanks for the video

[@pit81590]

Looks like it might be called a LEVER-BACKPLATE. PART # 823862 on my motor.

[@gregh2880]

Great video. Question: I noted that the water from the "tell-tale" was not a stream, but rather a spitting volume. Does the volume of water from the tell-tale increase when the motor warms up, or is this all that comes out?

[@ShnitzlHaus]

thank you Greg, I have noticed this on other Mercury 25hp from this vintage, on mine in particular it will be a constant spitting on idle and then smoothens out some, not sure if its just purging the air out from the initial start. when in gear its a solid stream. I was monitoring this when I took it out last but forgot to note its idle stream. I found this odd but some mechanics assured me its fine. I would be curious if any other viewers have input.

[@gregh2880]

More info from me: I just replaced the impeller on my 1998 25 Merc and indeed when first started, there is a very light dribble from the tell-tale. Within a minute, there's a solid steady race-horse pee stream coming out, presumable when the T-stat opens - ?

[@ShnitzlHaus]

I took the boat out last week. aside form a bad spark plug leaving me running on one cylinder, I did note the tell-tale. firstly I do have a thermostat originally I thought my engine did not, not certain why maybe because its so small! when the engine warms the dribble turns into a full strong stream. all is well :)

[@johnropeleski6006]

this is normal,when the thermostat fully opens,you will see a full stream of water coming out of the tell -tale.

[@sammymenfi1909]

Great vid

[@lindseygoodwin8757]

I'm having a hard time getting the lower unit to line back up right! i was wondering if you had any suggestions? thanks

[@ShnitzlHaus]

you are trying to engage 4 different components here, the pump housing into to the tube that feeds the water to the engine. the shift linkage to engage the shift arm, the drive shaft to engage the engine splines and lastly the dowel pins to align the lower unit to the midsection. I believe most difficulty comes from getting the drive shaft to engage the engine splines, to help with this put the lower unit in gear and spin the propeller slowly by hand to help get the splines lined up, or slightly pull the pull start (more awkward). it will take some doing to get them to slide together but when they do, it should be smooth and not forced.

[@dhajek2754]

i had the same problem. I tapped it with a 2X4

[@leemcguire7436]

What happens if when I pulled my lower end I didn't have a washer on the metal rod.like the one u said not to lose

[@mattmuch1]

Nice vid. Thank you. Can you tell me where you got the bent ratcheting wrench? I've looked everywhere for that exact tool.

[@ShnitzlHaus]

Yes the store is princess auto in Canada, they ship world wide. It is there professional brand “pro point” I can try linking later.

[@mattmuch1]

@@ShnitzlHaushey thanks for the quick response... that would be great.

[@ShnitzlHaus]

I cannot find them online. I wonder if I gave you the product number if you can call in and buy. I think they still stock them maybe just not listed online.

[@mattmuch1]

@@ShnitzlHaus yes. I was looking as well to no avail. If you still have the # that would be great I'll give them a call. Thanks for the time and efforts

[@SIMPLEARKANSAN]

ShnitzlHaus do you still have the kit product number?

[@ryanmiller5115]

I’m new to my Mercury 25. I’ve had Yamaha before. I’m just checking but my water stream is really weak like yours after the pump replacement. Is that the normal output? It picks up a little opening the throttle. But not a hard steady stream like my Yamaha. Is this normal?

[@dhajek2754]

mine does the same thing. I think it has something to do with the thermostat.

[@JoshVanHoose]

Well done!

[@poopyhead20002]

Would you be able to tell me when the fuse is for the electric start?

[@user-dj1gl5ix3m]

I just bought my motor, its used, and there wasn't a Shift Linage washer. Is it a Critical part?

[@John-of5sh]

I am just now watching this video which is why it took 3 months to reply. YES! You need that washer. I haven't unbolted my lower unit yet because I am waiting on the kit. I decided to go ahead and start the unbolting process and the first thing I noticed was I couldn't tilt the motor. The washer at the top of the shaft is what releases the catch that locks the motor down. You have to remove the rod (?) on the tilt mechanism that locks your motor down to tilt the motor back. If you don't install the washer sooner or later you are going to smack something, like an underwater rock or stump, and possibly do some serious dammage to your motor. With the washer installed the lock mechanism releases from the tilt lock allowing the motor to flip up instead of absorbing the entire impact. I am not good at explainiung things. Just take my word for it, if the washer didn't need to be there Mercury wouldn't have put it there.

[@badluk1]

Great video!! Thank you!! (And still scared to try it lol)

[@Dave-jc6ky]

Hi, Thanks for the informative video! We have a 1987 Mercury 2 stroke XD ELH outboard. I will need to get this done. I already have the kit. However while apart I also have a complete seal kit and need to get that done and change the prop and prop shaft seals too. There is a single, "plastic" perhaps nylon nut for propeller and I need to find out if it needs replaced each time the prop is removed. Hopefully someone knows the answer to that and if anyone knows of a video on replacing all the seals in this lower unit PLEASE let me know. Thanks!

[@7377alexis]

Great video helped alot

[@jacksonjuergens597]

Thanks for the help good vid will subscribe

[@RossWoodward-sg7ni]

Clear and concise thanks!

[@BladeRunner.43]

I thought I had the wrong impeller I'm like well that doesn't fit lol thanks for the vid

[@marcbtz9499]

After I did this on my 8hp 1996 mercury I can't switch to forward when turning the handle. What do I do? Great video

[@ct1762]

something is not connected properly. does it go into neutral/reverse? look on the starboard side shift cam linkages and make sure they aren't binding up.

[@shanester8712]

A local marinia changed the impeller for me last year. And it wouldn't go into reverse. Or unlock the trim latch in forward. Was told they didn't put the important washer back on told of shift rod. Guess I'll have to fix it myself now that I know how

[@rustic35]

When you pulled the leg off you had three rods/ shafts sticking out yet, when you put it back together, there was only 2?

[@rogern5368]

I have read and saw that the tube your talking about is easier to install first to set the lower unit back in place ! I saw it done with it still in place on the lower unit and the guy had trouble getting lined up. That video is the how to NOT do a job.

[@ShnitzlHaus]

Correct. It is much easier to put the tube in first then the lower unit. This way you can see if the tube fits in the pump. If you do it the other way it’s extremely difficult to know if the tube fit into the proper spot on the head and that can result in no waterflow and you taking the lower unit off again

[@rustic35]

@@ShnitzlHaus cheers. I was just curious because I'll be taking mine off soon.

[@leonarddutra1739]

i finished the impellar seems to be leaking all overis this normal

[@mspaz481]

very informative thanks.

[@liamwells7990]

Does the pin pass thru the spline

[@franciscorojas4631]

Can you show me where both ends of the linkage attach?