How to replace an impeller on a Mercury inboard 

this was great. thanks so much. Very much what we needed. if anyone is interested, I have typed up the steps here. Hopefully everything is right. Changing Impellor RU-vid: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-IX9A-_zNobQ.html Tools: 16 mm crescent wrench and socket wrench 0.5 inch socket Flathead (small one) Oil collecting bucket and pump Petroleum oil grease SAE 80W - 90 gear oil (about 1.5 quarts) Impellor and gasket MerCruiser Water Pump Impeller Kit, Alpha 1 - GEN 2 - EMP Replaces- 18-3214, 47-43026Q06 1. Place boat in neutral. 2. With 16 mm wrenches, remove 3 of the bolts on the side of the prop. Leave one on. 3. Remove bolt in back with 0.5 inch socket 4. Remove pewter silver plate in the front with 0.5 inch socket 5. Remove bolt that was under pewter plate with 9/16 socket 6. Remove speedometer line 7. Remove bottom drain plug for transmission fluid (have bucket under to collect). Remove top plug. 8. Loosen last side bolt (but leave enough on to catch the prop) 9. Separate the lower prop from the top 10. Remove last bolt 11. Remove lower prop 12. Remove screws for impellor housing with 5/16 or 8mm socket (2:55) 13. Open up impellor housing and scrape off the gunk 14. Replace the silver plate and the lock (4:17) 15. Lightly lubricate fins of impellor with petroleum oil grease 16. Put the impellor on (lined up with lock) 17. Lightly lubricate top housing of impellor. Add new gasket 18. Rotate the shaft clockwise to help put upper housing down on impellor. 19. Bolt in the housing 20. Place the boat in full forward position 6:15 21. Replace the bottom prop housing. Line up the tube (have it on the bottom housing). Line up the silver L shaped rod with the notch it fits in (7:00). Turn it so that when you move the prop blades, the shaft turns. You can turn the prop blades whichever way you want to. 22. Replace 4 side bolts (16mm). Replace bolt under pewter plate (9/16). Replace pewter plate (0.5 inch). Replace rubber plug over this bolt. Replace back bolt (0.5 inch) 23. Replace speedometer line 24. Lower prop 9:31 25. Connect pump to bottom transmission oil screw. Add gear oil 26. Pump until oil starts leaking out of top vent. 27. Screw in top vent screw (smaller one). Remove oil pump and screw in bottom screw (larger) 28. Fill gear oil reservoir in engine compartment. You should be able to spin the prop while boat is off (no clicking, not much resistance). In forward, the prop should spin one direction and click the other direction. When boat is on in neutral the prop may slowly move, but not spin. In forward, spins clockwise, in reverse spins counterclockwise. Water should not shoot out middle of prop with bunny ears on.

Just saw this. Very nicely done and very complete. I especially liked the fact you used hand tools and didnt have power tool everything. The Sound and your narration was excellent.

This is one of the best instructional videos.....NO extra talking, and vlogging. Just information and a clear way to do it. Thank you!

That gear oil that was drained out early in the video was definitely a milky color...that's a sign of water getting into the gear oil which is not good. Could be a bad seal somewhere. Great video though, I just replaced the impeller on my Mercruiser 3.0 Alpha One Gen II engine and it should be good to go for the next several years. It's undoubtedly easier when you have a helper around when reinstalling the lower.

When you tell the size of the Sockets it makes the job a lot easier so you don't have to keep running back yo the garage trying different sizes. Great video

I just started working on my own boat opposed to paying someone to do it for me. Your video was extremely helpful and so easy to follow on changing my impeller. Thank you!!!!!

Thanks, easy to follow directions i will be doing mine now. from know on instead of paying a shop. Save me money in the future

Could not have been shown any better, THANK YOU !!

Nice just seeing people take the time to try and help another person out. Good job!

the speedometer hose ! That is the part I couldn't understand. Thank you ! Good job !

Great video. Short, sweet, direct and accurate. Thank you

Thanks for the video man. It covered everything I needed to know for my impeller change. Good job.

I was going to beat you up on your tools. But by the end of the video, I could say that you are one of the best as explaining a simple process. I almost want to send you a set of rachet wrenches.

I like it...these esay's really know how to work fast and efficiently..no wasting so much time over explaining every little thing like other videos...bravo.

This is a great video, we appreciate the education. we have a 98 Maxum 1900 sr2 thats been sitting for awhile, not sure if im going to need to replace the impeller. but this video will help. Thanks

I wished I’d saw your video 1st. Straight to the point. Great video for us diy’ers.

Absolutely great instructional video keep up the good work. 👍

Thank you for this great video!! You are the only one in the net completely showing how to fix the tube when replacing the drive! I once had to repeat the whole work (without someone helping me) because the tube slipped off without me noticing it. Perhaps just one small hint missing: I usually put in gear in forward position when taking off the drive, then it is way easier to align the drive when putting everything together again. In neutral position it is almost impossible (at least for me)

Great job, I did not think it was that easy to do but you really did a great job of explaining the hole procedure, thank you very much for a very informative video😎🇨🇦

Great video, informative without the BS!

Thank you!! Very nice vid!! I learned something today. Now I have to change my impeller mine overheated and cooked my bellows

straight forward and clear explanations...well done...thank you!

Damn....you good! very thorough and fast...you have obviously completed a few rebuilds.

Good video. Very nice job of explaining how to change out the impeller and Gear Lube on a Mercruiser Inboard / Outboard. Nice job!

Great video....nicely explained and demonstrated Thank you for sharing

Excellent video...thank you for your detailed explanation. Super helpful!!!!

Great video I feel confident in moving forward now

Very informative and very thorough! Good job!

Your video was very helpful, thanks for posting it! Doug

Great video, straight to the point . Thanks

Excellent guide. Very thorough

You are the man! Thank you so much great video i watched a couple others before attempting this yours was by far the best! Saved me a lot of $$$$$ and grief!!

Properly the most helpful one I have watched

Awesome video I’m in the middle of doing this to my alpha one also. Nice 👍🏼

All I can say, is I watch a lot of videos on a myriad of topics. this is one of the most informative easiest to follow videos I've watched yet. Yes I am going to subscribe and follow. literally one of the very first videos I've watched where I felt like I could do it when I was done watching. Thank you guys

Hey, good job on the instruction bro. Thanks!!!!

Muchas gracias, muy buen video 🤘👌

Great video! I could sure use some of those gasket removal pliers too!

thank you for sharing this very useful information

Thank you you made this so easy for me to do.

Nice video. I recommend showing the oil seal replacement between the upper and lower halves. DIY guys may miss it.

Awesome explanations & great video!

Excellent job on this tutorial. Was wondering about torqueing fasteners. Why no torqueing? Got a new project and familiarizing myself and this was a great help. Definate subscribe and 2 thumbs up.

Great demo

Another Great Video... Thank you so much...

Thanks a lot. Really helped a friend of mine.

Brother, Thanks for the awesome vid!!

That has to be the best video I have seen in a while. Perfect Job. Quick, good video, covered everything!

Awesome videos it answers all my questions 👍🤜

Great How 2 Video, Thank You

Very helpful. Thank u!

Excelente amigo!! Ahora lo mismo pero en español para todos los que nos apasionan los botes.

Great video man. Very detailed and good camera action to see every part of the removal and install. Question; is there a diference in install if it's a bigger engine? I have a Mercruiser 5.0

Awesome video thank you!

Thanks for the video, I have just changed my gimbal bearing, bellows shift cable and trim senders, I installed a new sei 116 lower unit also but I am not getting and water out the exhaust port so I suspect the water tubes did not line up and there is water coming out the back of the drive. My question is have you seen this happen and do I have to drain all the oil out to check. Thanks

I've read that after you plug the vent screw, you should keep pumping until your reservoir is at the right level. That pushes all the air out

Gracias por el vídeo me va ayudar bastante para reparar el mío 👍🏽

Great video. Thank you.

Excellent video! You guys do it right so even a layman can understand-thank you so much! I have one question if you don’t mind I just started up my 350 magnum Chevy with a Alpha one for the first time in 5 years, although it was stored inside and had been put to sleep with a proper winterization with oil and filter change and lower unit change and antifreeze by the mercury dealer, and I siphoned and replaced all the gas with fresh and new fuel filter before starting, and it fired right up and sounded great! I was concerned because I only noticed water coming out of the left exhaust port and its an eight cylinder and from watching your video it should have come out of both right and left exhaust ports if I understood you correctly, that only the 4 cylinders just have the one port water exit? I only ran it for a few minutes because I was suspicious of a possible impeller problem or water blockage in the system somewhere and was by myself so couldn’t monitor gauges and water output very long jumping back-and-forth in and out of the boat to see what I could notice do you think I need to run it longer and see if the right port kicked in or just pull lower unit and replace the impeller like you did to play it safe? Thanks for your help and this great video! Dave

Thank you for the great video brotha ✊

Great Video , Thanks!

Good video. Thnx. I have to mine and this video will help.

Great video...thank you!!

Thank you for the wonderful video GT Performance. I recently got a used boat and tested it in water with no issues. However when I further examined the outdrive it appears the exhaust bellow is missing. But no water enters the boat. I noticed this when I put the trip WAY up. Would appreciate some feedback / input as to if I'm stupid taking the boat in the water without the exhaust bellow, or is it ok (assuming no water is enter the boat. Thanks in advance!

thanks great VID no BS, now off to the lake to fix my pump.

Very good video! Thanks

Great stuff

Great video ,thanks

great info great help

excellent video ,one question ,in neutral or in drive ,when you pull lower unit down. thanks .

Great video I have a different question my reverse dosent engage when I try reversing it dies out

Awesome video bro thanks 🙏

Thank you for this video man

Quality video, thanks

great video.

Great video

Perfect, thanks.

As a fellow RU-vidr, I want to congratulate you on an excellent video!!! Thanks for filming this and keeping it interesting. :)

Agradecido del video instrucctivo mi querido Chamo! Mi viejo bote (1989) tiene ha estado parado desde finales del 2020 por la bendita pandemia. Despues de conseguir los engine plugs del 4.3 Mercruiser (no me acuerdo donde los puse) creo que voy a intentar cambiar el impeller siguiendo tu video. En ese verano Canadiense el bote se uso muy poco y no estoy seguro de que necesite meterme en esa aventura del cambio de impeller. Antes lo hacia un amigo mecanico, pero nos mudamos por lados solitarios donde solo hay monte y culebras como diriamos en Venezuela. Favor tu consejo al respecto. Gran abrazo.

Good video!! Thanks

That was awesome thanks

Awsome video! I like how you described everything step by step and very informative. Thank you.

Since it is the only place gears are changed, fwd/neu/rev, it is the trans. I've done this several times on ours, wanted to watch anyway. Saves hundreds$! Good job buddy, keep boating😎🚤

Great Video Bro 👍🏼👏🏼👏🏼👏🏼👊🏼🇻🇪

Thank you very much

That's perfect brotha thank you, do you have any videos on the carburetor exact same motor, thanks for the help

Mi hermano gracias por este video esta BUENISIMO tengo una pregunta: mi bote liqueo el aceite por la parte de atras (en donde pusiste el ultimo tornillo) que crees que sea?? ojala y me pudieras contestar GRACIAS MIL

Awesome...Simple, to the point, well explained and very helpful--thank you so much!

Thank you for this video, esta chingon, its the best I have seen, your photography is great. good explanation. this is what i am trying to do for 2 days, but when i try to connect the lower unit, the shaft won´t slide up. it hits metal. have my gear it forward. i notice you are moving the shift stick in the back, is that so it will slide up ??? because i know its suppose to be straight, it pulls to the right, what is the secret ? also, i saw a man say to his helper to move the propeller. confused Pete, thank you. Gracias tecnico. por favor dime como le hago.??? what city are you in.?? another question, water was not going up to the engine, i disconnected the hose in the thermostat, and no water. so I thought its the water pump. but also could be its clogged, how can I find out which. thank you

Hey guys thanks for the video, never knew about all that. I am wondering if that impeller fits all models or is it unique to that certain model? I am trying to find out where to get the parts for mine. Thanks, I am new to boating aswell.

Just bought a used boat with the lower unit removed. Seller had a new seal kit that he gave me. Out of precaution and hassle free use, should I replace the universal joints along with the impeller? Also, is there anything that makes sense to replace when you don’t know the service history of the drive unit like the main bearing on/in the transom plate.

I have a Mercrusier 3.0 liter inboard/outboard similar to the one in the video. I was pulling a tuber when the engine seemed to lose power. It seemed like there was a vibration as I slowly took the boat to shore. What could the problem be?

😁👍Great Video

At exactly 1 minute into the video you showed a close-up of the bolt closest to the stern. THANKS! That bolt would not budge and got stripped for me. I tried PB Blaster for a week - nothing worked. I thought about torching it, but the plastic piece behind it would melt causing yet another problem. By showing that bolt, I was 100% that there were no threads on the upper drive. The top 1/4 inch or so has no threads - yea! So, I cut the head of the bolt off with a rotozip and got the lower drive off. My only complaint is that you should coat EVERY Bolt that goes under water with Anti-Seize. Every boat shop should do this. If this had been done on my lower unit, I never would have had this problem.

Great, thanks

Thank you 🙏🏼

I also have an external oil tank for the gears, it's leaking somewhere but don't see any oil leak on the floor, though when it's in the water i see oil rainbow slick. Any common place where to look? Thanks

Chaparral 246 oil showed 0 pressure but oil level was good Do you think it is just the sensor? Oil Pressure Sensor Sender Switch 3852215 for Volvo Penta 4.3 5.0 5.7 V6 V8 Thanks Jeff

good video

awesome thank you