The copper tube is the water 💦 intake it turns down to where the lower nut is at the water inlet. And also always put some lube on the impeller and turn the drive shaft clock wise when installing the impeller housing. And a little grease on the key helps keep in place while putting the impeller on. 👍
Watchers beware ! Turning that drive shaft counterclock wise while fitting the impeller is a no-no as it will fold the impeller fins the wrong way. Always only turn it clock wise, One needs to put the lower unit in gear before sliding it back in so spinning the prop will have the drive shaft turn and its plines align and slide back in the power head. Also, greasing the splines will greatly ease the sliding-in process but make sure no grease is applied to the top of the drive shaft as it might prevent it to seat all the way in. Finally, when faced with a slow flowing pee-hole, always first blow some compressed air up that hole as they often get clogged by debris. Regards to all !
@@curteouslycook Not a problem the fins of the impeller are self righting. I have done it backwards several times just to see what it would do and when I disassemble it they are in the correct position. There is a little plastic wedge build into the bottom of the housing so it will catch the fins and reverse them
Thanks for this. Got the same motor exactly. Dad bought it for our tinnie when I was about ten yrs old. Grew up exploring the lake with it. Such great memories. Definitely time for an impeller job!
I like the fact that you posted your video without editing out small problems you had butting it back together ( recommended to but grease on main propeller shafts after cleaning the fishing line ) which encourage the people that they can do it themself and not to worry about small problems. good video, I like it. (mechanical Engineer)
At about 10:48 is where I would have gone on a swearing and throwing everything I could get my hands rampage then I'd go in the house and put an ad on Craiglist to sell that #@*^#@#@#*** boat haha. I'm impressed with how you handled it. Thanks for the video, I was actually looking for where in the intake was for the water so I could figure out if the motor was deep enough in the water. Your video showed me it was hiding up under that fin when I was looking for the line of holes just above the propeller on the sides like a normal motor. I guess I have to have a barrel, the earmuffs won't work on this one. Thanks for taking the time to post.
Thanks a mill, man! I just bought an awfully cheap one of these also with impeller issues, so I'm going to change it some time very soon following your instructions.
Anytime, I hope this video helps you, it's good to pick them up cheap like this. Be sure to ask some questions if you hit any rough patches! The worst part will be realigning the drive and exhaust when re installing the lower unit
Nice video good advice for changing your impeller I had to do it to my Mercury motor last month a 8$ part save your whole motor cool good info but yeah I'm Rich Rod and we going to keep on fishing y'all alright Catch You Next Time!
Rob BassMaster thank you! I’m ready to start catching some fish over the open water again! I need to seal up my boat and I can reassemble to hook up and go! Thanks for watching!
S.D. Mountain Man I was hoping to have all this done for spring fishing and haven’t even started on the boat yet. Glad to have this out of the way time flies! Thanks for watching and commenting!
Awesome video JB!! You made that look easy brother. She was purring like a kitten. It's hard to beat an older engine like that if you just take care of it! Take care man!!
Very helpful video. I noted that the nuts on both locations were nylock, I never reuse nylock. They dry out and wont hold, so pay a buck or two and use brand new ones.
Hi, I bought the exact same engine and I am very happy with it. Since I have to replace the propeller, could you give me the right measurements: pitch and diameter? Thank you very much
Good video, but it looked like it was in gear when the shift lever was in neutral when you were running it? just wondering if something moved when you put it back together ? is this something I should look out for when I do mine. thanks
Yes that’s an issue is it’ll move if you bump the prop during install and throw off sync of shift lever. This one came back apart after the running portion of the video and I cleaned up the shafts and realized that. Thanks for watching, take care
Hey bud, nice video! Very knowledgeable. I have a quick question. when the impeller goes in, is there a side that should be more narrow than the other?
Every impeller I’ve ever done has always had one side that was more narrow than the other. It’s been the same on larger engines I’ve done as well. Thanks for watching! And I hope this video helped
Thanks for the video, I'm doing this at the moment and I'm stuck trying to get the new impeller in place with the key. Even using grease I can't get it in. Can you share some more footage or do you have any other tips?
Ben Waywood I don’t have any more footage of this, but what has worked for me with other impeller jobs is turning the lower unit on its side and having the flat part of the shaft facing up WITH grease holding the key in place. I hope this helps, for me it usually fell right into place with the lower unit on its side
Ben, I just saw on another video on the same topic that there are two different diameters of impeller. Might be worthwhile checking that you have the correct internal diameter. Seems a bit rude to link to that video here since JB gave such a good demonstration.
Richard Ventrello thanks Richard I did forget the o ring, I remembered the rubber band on the top of the pump, but added in scrolling text in the video while editing to remember it. Thanks for watching and commenting, take care
When you installed the impellor you turned it counter clockwise folding the vanes opposite the normal direction , which is clockwise. Greasing the vanes is a good idea but I would recomend silicone grease , petroleum bases greased will attack the rubber.
I’ve been told this many times about direction of the veins, but I’ve tested in forward and reverse while I had the lower unit removed and found that veins have enough room to reverse inside the impeller housing. I’ll keep that in mind about the grease, makes sense. Thank you for watching and commenting
The gears in the lower unit cause the prop to go forward and reverse. The shaft always spins clockwise. Hopefully like you said they can fix themselves.. on bigger motors the impeller rubber is too thick and stiff to allow them to flip the correct way. Out of curiosity did you actually see them flip when you rotated the shaft clockwise?
Hi mate, I have the same engine, same year and everything. It came as an auxiliary engine on a boat I bought. It runs like a champ but I done seem to get full throttle. There is a lever on the back of the carb, if I pull that, it revs much harder. It looks like it should be connected to something. I'm wondering if I am missing some kind of linkage? Can you shed any light on it please? Cheers from Tasmania :)
Music Islife absolutely, the lever on the back of the carb goes up to the linkage system for the twist throttle. When the engine is in neutral it’s meant to prevent over revving with no load on the engine. As soon as you engage into gear a cam lob is moved to push that throttle lever further open. I hope that helps or if that’s even your problem. Mine was also an auxiliary engine and being a longer shaft on my 12 ft V Aerocraft I had to install a jack plate to raise the engine some
JB Outdoors oh, I see. I haven't even tried it in gear yet, I only started it for the first time today. I think it's been at least 10 years since it was run and it started after 3 pulls! Runs like a champ. So if I click it into gear, I should be able to get full throttle?
Music Islife nice runner! Yes it’ll go full throttle in gear, I recently had to remove my carb for cleaning and learned more about that. Thanks for watching!
You’ll have to remove the lower unit again and spin the shift shaft accordingly. I’ve had this issue as well as its pretty common while lining up the splines, the shift lever can move easily without noticing. Best of luck, thank you for watching
It's a great motor! Mines currently in storage, but thats a great idea for a video in the spring! Until then, I'm sure there's a few great videos that may explain further if you're in need of answers soon. We're currently experiencing a polar vortex in Michigan! Thanks for watching, take care
@@ATLRCFlyer That's correct and when filling pull both and fill from the bottom port, when the oil starts to run out of the top port that's when it's full.
whitey badger i bought my kit on amazon, just be sure to have your serial number handy and know the shaft size as depending on the year they used two different diameter impellers. Your serial number will tell you which one on a figment guide on amazon. Thanks for watching!
Twisted Jig Co. er, yeah, except it doesn't work. I put in my serial number and it told me my 9.8 was a 4.2 litre sterndrive...which it clearly isn't :/
I was given an older 7.5 mercury outboard that looks a lot like the motor you have. The lower unit was just partially pushed on and the two nuts are missing. I don’t know what gear it was in when the lower unit was removed. How can I figure that out? The unit does not push all the way together with the motor and I am afraid to force it. Any ideas? Also turning the propeller does not turn the spline... what does that mean?
If you pull the lower back out, you can shift the lower unit by spinning the shift shaft to the selected gear. In my experience, when you can't push in all the way, the splines on the motor and the splines on the shift shaft are not lined up perfectly. I've spun the prop while the lever on the motor and the shift shaft are both in Reverse to help line up the splines easier. Just be sure the gears match each other or you'll be pulling it back apart to do it again. (I've had to do it before) Thanks for watching, and I hope that advice helps
JB Outdoors Thanks for answering.... I did have to rotate the main shaft multiple times before it would go together however I couldn’t get it closer than about 1/8 inch .... after watching your video a few times plus a couple of others I finally discovered the problem. When I drop the lower unit the shifter rod is staying with the upper unit instead of coming down with the lower unit. So far I haven’t been able to pull the shifter rod loose from the upper unit. It looks like it sticks into the lower unit via a couple of O-rings. Not sure what is holding it into the upper unit unless it is corrosion. Still working on that problem but now discovered the engine is seized. Started a SeaFoam Deep Creeper treatment.... hoping I can get it free....
why does it matter about the gear it was left in? I am waiting for parts to do the same thing. I have watched several videos of this process, can this be done upside down? Meaning if the motor was completely upside down so as lowering the splines down, possibly being able to see more as to the spline alignment? I know zero about boat motors so maybe there is something obvious I am not aware of. Thanks for video and any help. In reading some comments before posting this, something about the impeller being more narrow on one end and that goes in first???
The gear indicator lever can move on you and when you put the lower back on, the timing will then be off. For example if you left the boat in reverse and when taking apart and the shift shaft turned on you during this process, when putting it back together the lever could show reverse but the lower unit would actually be in neutral or forward. You’d have to take everything back apart to correct this. When you get access to your water pump, you’ll find the impeller and the hole it’s in is almost offset by a small amount and the narrow end is the end you’d start in. Take your time and remember how it came apart and you’ll be just fine! Thanks for watching, if you have any more questions feel free to reach out, I hope this helps
@@JBOutdoors If the entire unit is upside down, so you are putting the lower half down as opposed to going up, will that allow a visual way where the shaft would go? your video and several others seem to have difficulty when fitting the lower part upward. Some mention the impeller being slightly narrower on one side, is this obvious or how do you determine which way the impeller actually goes? Thank you so very much for not only your video, also the promptness in which you respond.
I attempted this today. What a nightmare. Shaft splines are all messed up. No matter what gear I put it in it does not engage properly. Impeller didn't spit water and it broke on first start. I can get it in reverse and neutral but forward just grinds. How in hell do you get splines in right alignment? Thought this would be easy, but it is far from easy. HELP! Prior to this the motor ran perfect and spit water, but it was old so figured should change impeller!
Having trouble with my 7.5 hp Mercury, it’s not pumping water, put new impeller in blew shop air in to make sure it wasn’t clogged even ordered a new water pump housing still not sure what’s up with it, any help would be greatly appreciated
Definitely, it could be that your thermostat is failing and/or clogged as well. If some of your old water pump impeller made it to the tstat it could plug the entire line easily. That’s where I’d look next! Thanks for watching
@@JBOutdoors sadly don’t have a thermostat that was my first guess, there’s a little plastic spicket under the power head that was melted poked a hole through it and she’s good now hopefully if someone sees this that’s checked everything else this may help
I am changing out mine but I cannot get the shift linkage to release, cannot pull down the lower unit. I did not see you do anything to release it. Help? Thx.
Glad you got it, I didn’t have issues with that but when pulling apart just remember which gear you’re in and what get it’s it when putting back together that’s the biggest issue I had! Take care and thanks for watching
Did you see a sheer pin when you took off the prop just asking. I broke one on a fishing trip and it made for a long day of rowing ☹️ After that I carried one in my billfold for years. And let me tell you there’s nothing that will replace a sheer pin. No nails barb wire fence nothing I tryed them all. Be safe and get one for your motor and keep it in the boat.
There’s no sheer pin for this particular motor, but that’s a great idea. They’ve saved me in the past for other applications. Thanks for watching and commenting
After I installed the impeller i stared the motor in neutral and the prop started going like it was in gear. Did I not align it right when I put it back in?
Your shift shaft moved during installation of the lower unit. It happens easily as it only has to move a few splines to shift into gear. I’ve had it happen before as well, no big deal just have to remove lower unit and find the same gear as the shift lever. Sorry for the delayed response, take care
Hello, I'm sorry I do not have any sort of markings on this prop and unsure how to located myself. I am considering selling this engine as it has sat for over 2 years!
I ordered my kit from amazon just have your serial number handy to know the correct shaft size as they had two different sizes on different years. Thanks for watching, I hope this video helped
I bought this kit through Amazon.com. This one was for the .456 shaft, but some were built with .438 shaft. If you have your serial number when purchasing you’ll be able to see which exact kit you need. I hope this helped!
Kavon Woods could be a plugged or broken thermostat or a blockage in your water inlet line I haven’t made a video on these yet but I’m sure something is out there! Good luck I hope it helped with the impeller swap
JB Outdoors thank you! Now I’m trying to figure out why my tiller handle won’t twist all the way when I am in forward gear. If you know anything let me know please.
Haven't read all the comments, but b/c of imo questionable engineering, you have to compress (I used a small radiator clamp) or similar to squeeze the impeller, making sure all fins are bent LEFT from top. Even a cylinder, inside diameter smaller than housing, holding the impeller would work. Apply a little LITHIUM grease to fins b4hand. Dab a spot of white paint or liquid eraser on the upper side of the impeller where the keyslot is located. Dab also on housing where the key lays in the shaft. Apply something sticky, or grease to backside of key to hold in place. LINE UP. Use some sort of cylinder to push the impeller into place. Could use a hammer or similar to tap down. MAKE SURE YOU ROTATE THE SHAFT AFTERWARDS to note that the impeller is indeed located onto the key. Much more cumbersome than OMC, but it is what it is
Great advice, I was lucky enough to turn to the left with grease on the key and everything slid into place lined up first try, but I’m sure people have a hard time getting everything to do so
Definitely here’s the kit for my serial number, I’d be sure it’s within your serial number range before purchasing. There were two different size shafts with these engines depending on serial: www.amazon.com/uanofcn-Repair-Mercury-47-89981Q1-47-89981T1/dp/B07DD6TZZZ
Christ, the fins on the old impeller are all bent and hardened up and that exhaust tube you took off is the WATER tube grommet the water tube slides into.
Thanks captain, we all make mistakes sometimes. If you already knew how to do it and know what you're looking at, why are you wasting your time watching a how to video?
Mark, I know I made a mistake saying it was for the exhaust and not water, you were right with what you said. I’m new to making RU-vid videos and still stumble and make mistakes in front of the camera. Ive only done a handful of impellers and usually they’re broken and shredded this was the first one I’ve ran into that wasn’t so it threw me for a loop. Thanks for watching
You skipped the whole reason I tried watching this video, which was seeing the actually process you used to get the impeller in place. It's super difficult, but in the video you push it down, then cut and it's magically in place with the fins twisted.
David Shannon push down and twist at the same time after getting the jet started in place. It’s not only hard to do, but it’s hard to capture it when your hands are blocking the camera, I apologize if the video didn’t help at all.
You can also lube the impeller fins with a small amount of vasallien, note the location of your key. Then rotate the impeller slightly to set the fins then push the impeller down into the housing.
I cheated. I have a lathe in my basement and I used it to make a cylinder to squish the impeller into, before slipping it over the shaft. This really makes it easy, since that key doesn't stay in place. BUT......... the impeller isn't dead-center, you'll have to use a screwdriver to pry the whole "cylinder tool" over to one side, squishing the impeller "off-center". If you have access to a lathe, and can make a cylinder..... mine was 1.08 outside diameter and 1.03 inside diameter. The piece was .75 think and I only turned the I.D. a half-inch deep so it would retain it's shape while I had it in the chuck. I hope this makes sense, I'm a machinist, and I know... not everybody knows what I know.
one thing I've noticed in most videos. theres always something not explains that one maybe needing to find. for example putting it back together whether in forward or reverse position its said either or but then one will have a preference in reverse and will show you why. then never does. the dos and fonts of talking apart and what can happen is actually very important for a guy who does not do things often. and looks for that in a video almost step by sep with pics is great. I won't watch one that skips steps nor doesn't explain. sorry but not helpful in many ways with this video.
Ryan Kurr the purpose of the gearing is to remember which gear it was in when you took it apart so when you put it back together it’s in the same gear and the shaft hasn’t moved. I’m sorry if I didn’t explain that well enough. In my video I said I left it in neutral for reference. I’ll remember this advice for any future how to videos I do. Take care
@@JBOutdoors I did the same job, plus some bushings, so the gears got misaligned. Oh man, trying to get it back together where it shifts properly has been a royal nightmare. IMO, this is such a ridiculous design-- it shouldn't have to be this hard.
