How an outboard gearbox works

[@johanfalkmarken]

You are a great teacher, and the level of commitment, cutting the gearbox in this video, is 1:st class. Cheers from Stockholm, Scandinavia.

[@Kurtdog63]

Brought a boat in that had shift issues to be repaired. After looking at the damage in the lower unit, the mechanic asked me how we shifted the boat into gear. He stated the worst thing you can do when shifting a boat from neutral to either forward or reverse is to do it slow and gently. That motion needs to be somewhat quick and deliberate so that the two metal parts mesh quickly to reduce wear on those two parts. Another thing I found out later on was shifting involving a stainless steel prop. Because a stainless steel prop weighs so much more than an aluminum prop, I was advised when shifting from reverse to forward or vice versa, to go to neutral and allow a short delay before shifting to reverse the spin of the prop. This delay in neutral was to allow the heavy stainless prop to come to a stop before reversing its spin. Hope this helps someone so they don't have to learn the hard way. Your lower unit cut away is awesome by the way. Thanks for sharing.

[@cjsshed3849]

Best video on KZbin explaining how outboard gearbox works , saved me loads of time and money

[@chuckbelliveau2543]

That was probably the best video I’ve ever seen showing how the driveshaft actually works on an outboard motor it really was very clear and easy to understand exactly how that worked

[@dunderclumpin]

You keep your audience engaged and not overwhelmed by pointless content. Thanks mate i'll be watching more.

[@hunterbaum6921]

I just want to let you know that I have been glued to your outboard videos the last few weeks. I bought my first boat with a 60hp Johnson on the back and you have been more than informative about my new boat. Cheers.

[@DangarMarine]

Thanks mate, good luck with the new boat! :)

[@davidharlem6824]

What an effective teacher you are! (That’s from one teacher to another). Your videos are unique and that is why your audience is so large. Some channels post videos almost for the sake of it and viewers quickly pick up on that. Your viewers know they are going to get the real thing EVERYTIME.

[@DangarMarine]

Thanks David, glad you liked it. :)

[@cmetz100]

Thank you for posting this!! I know it was posted 7 years ago, but it’s extremely helpful after all these years!

[@marksievers]

Man, this is gold! You are giving average chumps a chance to succeed! It was all magic inside that casing until you cut it away and explained. Beautiful in its simplicity.

[@chrismaconachie4571]

Just found your site in the last coupler of weeks. Refreshing to see a hands on delivery. You have saved me a lot of heart ache. Cheers

[@DangarMarine]

Welcome aboard! Glad to hear the videos have been helping you. :)

[@premitive1]

Imagine my surprise when in my Marine Transmissions class at Broward College in Florida, USA, my professor put on YOUR video to show us a clear example of outboard marine transmissions? Been watching your videos for a few months now. You produce fantastic content!

[@DangarMarine]

That’s pretty funny, glad the video is helpful! 😊

[@Bubbamoo_vintage]

I have learned SO much by watching your series. Just wanted to say thank you for all the effort you make to share your knowledge with others!

[@Edcognito]

I just wanted to add to what everyone else is saying here - Thank you!Wonderful explanation / demonstration.

[@DangarMarine]

Thanks Ed!

[@jeffselano2300]

Mind blown. Thank you for such a detailed and well spoken explanation.

[@Fourandaquarter]

Again, great video. I had a mental image of how these gearboxes worked but the cutaway really shows nice and clearly how it's done. Nice.

[@DangarMarine]

Thanks mate, glad you enjoyed. :)

[@simonafloat]

Your videos are so useful - many thanks. Just stripped down my old 4hp tohatsu gearbox and replaced all the seals.

[@DangarMarine]

Nice work! :)

[@pressak]

Just wanted to say thanks from Northern Ireland.The video's really help. As the poor sod in a local fishing club who does the maintenance, your video's are invaluable to me.The explanation of the gearbox lower unit is great.

[@DangarMarine]

Thanks Kenneth, good luck keeping those fishing boats on the water!

[@eugeneanderson6316]

Dangar Marine : I took the thermostat out of my 1977/85hp. Evinrude and am now having trouble getting it back together, not sure which spring goes to the thermostat.need illistration.

[@mikekovar1345]

Thank you for being here to help teach us about outboards!!!!!!!

[@DangarMarine]

You're welcome. :)

[@LaughingRandomly]

the outboard motor is truly a bit of marvelous ingenuity, now more so than before viewing this video, thank you!

[@DangarMarine]

They are pretty amazing pieces of engineering. :)

[@armytruck08]

Just the bearing carrier came out leaving the roller bearing at the bottom around the prop shaft . Need not worry anymore . I pulled out the shift rod then blew air through the oil fill hole and wala. That piece of metal blew out and smacked my hand so , I had a beer and a shot of Jack Daniels , gunna get pissed instead of pissed off my friend . I'm so happy , and so appreciated with your help trouble shooting .

[@DangarMarine]

Nice one! Have a JD for me! :)

[@osbornebay944]

You are the great teacher to us part time tinkers of small engines, thanks a million.

[@DangarMarine]

You're welcome mate. :)

[@gscfishingoutdoors]

thanks for tearing into an old lower unit to explain the drive gear and dog clutching operations, helps a lot to actually see the process as I'm trying to narrow down my engine problem. Thanks mate!

[@DangarMarine]

+giovannis62 You're welcome, glad it helped. Good luck with fixing your problem. Let me know if I can help.

[@kgnok2020]

this video takes the mystery out of how the lower unit gearing works, thanks.

[@DangarMarine]

You're welcome, have another one on the clutch and gear selection mechanism coming soon.

[@guillermorodriguez1071]

@@DangarMarine dirección de taller donde reparan transmisión de un yamaha outboard four stroke 150hp año 2006

[@guillermorodriguez1071]

Necesito reparar transmisión de un yamaha outboard 150hp año 2006 four stroke

[@kareemmagill709]

I found your outboard series when i started having trouble Edith my enduro 15hp. You give very useful education on the i depths of how these engines work. Thank you danger marine and cheers.

[@carminec4000]

I have learned a tremendous amount from you and the videos that you so thoughtfully and intelligently produce. Thank you for what you do for everyone around the globe. I'll keep watching!! 👍

[@DangarMarine]

Thanks mate, glad you've been enjoying the vids. :)

[@carminec4000]

@@DangarMarine And...I've started purchasing parts through Marine Engine. Has been very painless process. 👍

[@kennethkelley2895]

ever grateful for this tour. Education and Understanding are the fundamentals of life and your generosity in helping is to be applauded. Thank you.

[@johnschumacher3618]

John from Minnesota. Been watching u for quite a while always entertained. And learning more and more bout engines. That I thought I new. U make things very clear. Thanks. We here are having -20 degrees Fahrenheit. With windchill to 30to 35 below. And have 30in snow in one week wish we could enjoy some of ur weather. Without the bug s. Good work mate.

[@andrewngawaka3764]

hi i just got my first boat never been on water befor after seen ur videos i have just rebuilt a old mercury 50hp 1970-80 model motor from watching ur videos thank you sir :-)

[@DangarMarine]

Nice work! So great to hear the videos helped you. :)

[@DangarMarine]

+Andrew Ngawaka The more I think about it, the more this makes me happy. It's great to hear that this channel has helped people get out and enjoy the water. I hope you have lots of fun times in your new boat.

[@capnchip]

ABSOLUTELY FANTASTIC....best on the internet....bar none! T H A N K S !!!

[@pfpublius]

Hands down one of the best videos on KZbin

[@samsgarioto459]

This is just brilliant!! I had no knowledge of how all this works, it now makes a bit more sense. Many thanks for your explanation of a very important part of the boat. Well Done!

[@El_inge_987]

Your videos are AMAZING. I like how you not only show people how to repair motors but also explain how things work.

[@motorv8N]

Just discovered your channel and this is one of the best videos I've seen in a long time. I've been boating for over 40 years and love to tinker with all things marine... but usually just above the waterline. Until now I've never really been clear on just what is happening in the gear case of an outboard motor. Your commentary along with this excellent visual prop (pun intended!) makes it perfectly understandable. Well done mate. Consider me subscribed!

[@DangarMarine]

Thanks mate, glad you like the vid and great to have you as a subscriber. This channel needs more cunning linguists!

[@kevint9702]

@@DangarMarine Do I need special tools to rebuild a gearbox? KT from USA Love your vids!!!

[@dwd125]

New boater here... can't thank you enough! Dealer was annoyed w/ all my 'how does this work' questions. I was only asking so I could better understand maint. procedures and what to look out for to not kill a motor. Seems they get annoyed b/c they don't know. This video although fundamental for some i'm sure was huge for me. Thanks again...subscriber!

[@DangarMarine]

You're welcome mate, great to have you on board! :)

[@thehappytexan]

I never took that apart when I owned an I/O and always wondered how it worked. Awesome job on the prop man. Good video.

[@thomasslater3776]

Thanks, please keep making these videos. As a newer power boat owner without a nearby mechanic or marina, your videos have helped me get a few problems sorted.

[@northerniltree]

Bloody hell. And all this time I figured it was just magic that goes on in the lower drive.

[@myvalium1]

That was incredibly helpful… I’m by no means a mechanic but always eager to understand issues and how they should be resolved

[@DangarMarine]

Thanks mate. Glad you enjoyed it.

[@MitroBurner]

Another excellent video thanks Dangar. Love the cut-away - that really helped see how it works and now I doubly appreciate your efforts to make this video.

[@DangarMarine]

Thanks mate, glad you liked it. :)

[@locker1325]

A very clear explanation of what is going on in the lower unit.

[@romeowhiskey1146]

One word: EXCELLENT.

[@DangarMarine]

Thanks mate!

[@user-JHack]

I just recently replaced the o ring and prop shaft seal on a Mariner 15 hp. Your video really helps, as its nice to see what I was dealing with.

[@michaelwilloughby7215]

Happened onto your channel by accident. Thought the title was DANGER Marine and thought oh this might be a bit of a laugh and clicked on it. MUCH to my surprise I found what I consider to be the BEST maintenance channel on the net. I am a licensed Airframe and Powerplant mechanic, and have a lot of maintenance and repair experience, all on aircraft--none on boats. So I was very pleased to find an INSTRUCTOR of such high caliber. You take the mystery out of the equation. Now I feel better equipped to maintain my new to me sailboat kicker engine. Thank you for such great vids! Of course I subscribed after the first one I watched. Keep up the good work.

[@DangarMarine]

Thanks Michael, glad to hear the channel has been helping you look after your kicker. All of your mechanical skills will translate nicely to outboards once you become familiar with them. :)

[@terryhites1]

You do the BEST job of explaining things in terms I understand and I feel much more competent to make repairs on my boat! You have taught me about trim tilts, spedo holes plugged, now about the lower drive unit! Thank you so much

[@Peter-ss1vb]

Well I never knew how the gear box worked, thanks

[@mickcv4554]

Nice man, work at an insurance company where they did similar cut out the sides pulled the carrier and hooked a little electric motor to the drive gear to show it. Simplicity of these motors is pretty ingenious, seem way more complicated than they really are. A little explanation can really help people take care of their boats. Especially the dog clutch, so many think they gotta ease into gear which is terrible for it when you see how it chips the crap out of it.

[@andywoof7360]

A tip as to how to operate your outboard. Our dive club bought a RIB with a 150 Johnson outboard, I'm the guy responsible for maintenance. When reverse gear was engaged, it would "jump", by that I mean it felt like it was in gear then went to neutral for a fraction of a second, then went back in gear. Eventually it lost reverse. On gearbox disassembly, it was found that the dog clutch had worn away the dogs on reverse gear. I came to the conclusion that this was due to the previous owner "easing" it in to reverse, clunk, clunk, clunk, rather than pulling the shift lever back decisively to positively engage gear. This wore down and rounded the edges of the dog on the reverse gear and eventually made it so it wouldn't engage at all. As the price of a new replacement gear wheel was rather silly, I sourced a secondhand gearbox with problems, but it had a good reverse gear, and used that to make a good unit out of two, for much less money. The lesson from this is, when engaging either forward or reverse, shift gear decisively, secondly, don't ram your gearbox into reverse to slow down unless it's an emergency and absolutely necessary. Ease off well before you have to stop, hit neutral and let the boat spend its energy, so you are virtually stopped by the time you you reach the dock, buoy, or whatever you wish to get along side, or moor to. Always operate your boat with the utmost sympathy, and it will pay you back handsomely. That doesn't mean you can't work it hard, but think ahead and don't subject it to any unnecessary strain, which could be avoided by anticipation and intelligent boat handling.

[@DangarMarine]

Changing gears decisively is definitely a good way to keep the dog clutch in good condition. I had a similar problem with this gearbox but just had the clutched machined for only about $20 kzbin.info/www/bejne/eGXElIaclKeahpY

[@andywoof7360]

Hi Stu, all of the wear on the Johnson was on the gear, not the dog clutch. I had the dog on the gear machined, as you did, but it soon wore out again, despite lecturing operators to engage gear decisively. I assume this was due to the original gear being case hardened, when the gear was machined, I think it removed the case hardened layer and the material underneath was soft. The fact that yours lasted after machining may say something about the quality of Japanese components ;-)

[@jazldazl9193]

Excellent advice. I think the following also applies to cars and all machinery, paying off in the long run in reduced maintenance/costs/profanity Always operate your boat with the utmost sympathy, and it will pay you back handsomely. That doesn't mean you can't work it hard, but think ahead and don't subject it to any unnecessary strain, which could be avoided by anticipation and intelligent boat handling.

[@lautoka63]

I was initially put off by the low volume, but I'm very glad I stayed with you, as I've learnt a lot.

[@samgreer8596]

Your videos are absolutely inspired. I love the videos and your explanations. Fantastic!

[@DangarMarine]

Thanks Sam, glad you like them! :)

[@jimmyjackson2361]

I’m having trouble with mine not going into reverse. Mine is a Mercury so it’s not exactly the same but your video helped me understand how the gears work. Now I just need to figure out how mine shafts. Thank you so very much. You do a tremendous job!

[@daimlerblanco4534]

You are amazing men thanks for your free lessons lol

[@DangarMarine]

You're welcome. :)

[@WaterpowersolutionsAnkeny]

Dangar Marine trying to replace a prop shaft on volvo penta and can't get the gears to line up inside I didnt know if possibly had to remove a part or removed vertical shaft and place prop shaft in first for gears to line up if this makes sense thank you

[@kaavest]

Cool vid,i blew up mine due to water in box over time on a tohatsu 25. 4 stroke, but found a new used one from a drowned engine and the store replased impeller seals etc and it worcs like new with little noise etc.Whole gearhouse with internals replased to 1 third of new prize .

[@horus2779]

Awesome thankyou, i have 50mm crack in gearbox housing at front that has not reached seals yet, do you have any weld videos on gearbox thanks

[@johndejonckheere]

Daimler Blanco bb

[@nyinfamous2k2]

20 something years of boating and I never knew how this worked . lol. thank you for all your great videos

[@devo500]

"Crenellations" I think is the word you were searching for when talking about the dog clutch. 😄. Like the tops of English castles. 🇬🇧

[@markusantonio4866]

Battlements, too? Crenellations, that's a great choice of words

[@miruton1]

New to the outboard motor world, your video presentation really makes it easy to understand how things work.

[@snickermon]

Super informative. Thank you for making these videos and keep up the good work!

[@DangarMarine]

Thanks James! :)

[@mufuliramark]

I haven’t had an engine in 40 years and even then it was a pull start seagull 5 but I love this topic and watching engine repairs.

[@helgedell]

Very educational. Even I understood it :) Thanks.

[@DangarMarine]

You're welcome Helge. :)

[@helgedell]

Just change impeller on my 1983 model of Mercury 80 hp. Functions great in forward and neutral. In reverse the propeller is blocked in both directions. Do you think it has to do with my mistake of throwing it in reverse last time I used it on to high rpm? According to your video, the tooths on the reverse side are deformated?

[@josepeixoto3384]

i didn´t understand EXACTLY how that dog clutch gets movement from that vertical shaft,amidst that rotating assembly; i will continue searching,

[@tomthompson7400]

Thats the best demo of that ive ever seen , cut away works perfectly.

[@dana1723]

Thanks for all the easy to understand video for a first time outboard owner , really helpful. B O A T. break out another thousand. LOL

[@DangarMarine]

You're welcome, hope the videos help you save a bit of money on your new boat. :)

[@ivarvikigs420milz3]

So true bro spent like 2k in just boat alone lol

[@mcdermottrobert]

This is the best, by far, video to explain an outboard gearbox. Thanks Stu for the invaluable instruction you have provided over the years!

[@derrickcarter912]

outstanding! Great explaination, thank you for your time mate.

[@CLYONS.CREATIVE]

Awesome video!

[@DangarMarine]

Thanks mate.

[@divingstcon]

Great help, Sir! Me and my boat co-owner are not dummies in mechanical works, but dummies in boat engines, and your videos help us a lot to understand where and how local mechanics are cheating us with services and repairs. :)

[@annachanel2174]

good work...

[@easemailboxes]

This is a great explanation, for someone like me who is starting from a knowledge base of zero , it really has helped me so much. I have enjoyed your wholes series. Thanks again.

[@DangarMarine]

You're welcome, glad you enjoyed it.

[@Gazgit555]

good vids muka

[@DangarMarine]

Thanks mate. :)

[@mhlanombembe5510]

I must say yu make me so clear of how outboards work ...This is short video but I must say it really useful adding to my knowledge about outboards

[@DangarMarine]

Thanks mate. :)

[@souljaboyteelemify]

IVE SUBSCRIBED and I'm think I'm now your #1 fan. Who else would cut out a section of a lower to show how it works, BRAVO

[@DangarMarine]

+Bassmaster Florida Great to have you aboard! :)

[@freshair9315]

Kudos to you Mate. Thank you so much for sharing your wisdom and thought processes. Your humility and earthy naturalness is fantastic. All the very best.

[@DangarMarine]

Thanks mate, glad you enjoyed it.

[@Mr_Reaper]

Useful video, thank you for sharing your knowledge. Having worked on inboard engines for a number of years, I always thought outboards were the work of the devil and avoided them at all costs. Things like this are good to know. A simple, yet effective system

[@grantlarmstrong]

I realize this video was made a while back, but thank you for taking the time to do this. Very informative.

[@DangarMarine]

You're welcome Grant, glad you liked it.

[@Albert-wk8ts]

Never understood how a gearbox worked, but this definitely cleared things up. Thanks!

[@robwooly]

I had a hunch that this informative and educational video would be made here... And I was right. Thanks for all your great videos, you've been very helpful so often, your a true legend!

[@patrickrede]

Thanks. Just took one apart and now I understand what moving the shifter does.

[@centralcoastcamper9631]

Great illustration on explaining how a lower unit gear box works, I learned something. Thank you.

[@radoslawfilip3758]

I'm from Poland and KZbin, no videos explaining the construction of engines, etc. a good job. thanks for passing knowledge

[@DangarMarine]

Thanks Radoslaw, glad you liked it.

[@saqibnawaz5139]

Viry simplest & concise illustration of outboard gears engagement

[@ballhawk387]

Excellent, crystal clear, and much appreciated. I have a c. 1980 Merc that's grinding a bit when shifting, and found this very useful... and a bit reassuring. Good work, mate!

[@DangarMarine]

Thanks mate, glad you liked it. :)

[@joseascensao4200]

Yes, once again ..a fountain of knowledge and information for rookie boaters like me. A must watch to go along with all Dangers great videos. Well done and thank you.

[@DangarMarine]

Glad you enjoyed it

[@joeblowjohnny2297]

Very straight forward and very thorough ! I have NO question at all ! Thank you !

[@DangarMarine]

Great to hear, you're welcome. :)

[@welshnutterz]

thanks for taking the time to cut the box open and show us.

[@DangarMarine]

You're welcome Elwyn.

[@machgt]

Good stuff to see for real! I should have checked this out and got the manual before changing the impeller on my zuki. I didn't disconnect the shift rod, now I get to pull the gears out!

[@simoncorporation3]

Excellent Elementary illustration worthy of textbook instruction thank you for sharing.

[@DangarMarine]

Glad you liked it. :)

[@garylewis327]

Excellent explanation on how these lower units work. I had one that was a little different though, and wondered if you had ever seen one of these. I had a little runabout, 1960-something, Larson, and it had a 75hp Johnson outboard. One day it quit shifting into gear. It wouldn't go into forward or reverse. Always stayed in neutral. I took it apart and found the problem. Like the one in your video, it had a forward gear and reverse gear that were always engaged. But it had no dog pawl. The forward and reverse gears were connected to (or a part of, I can't remember exactly) steel cylinders (one for each gear) with cross-hatching on the outer surface. These cylinders were directly connected to their respective forward and reverse gears so would spin with them all the time when the engine was running. There were heavy steel springs that wrapped around each of these cylinders, and these springs had a slightly larger inside diameter than the outside diameter of the cylinders that they were wrapped around. Just beyond each cylinder were matching cylinders that attached directly to the prop shaft. And just beyond those cylinders, at each end, were electromagnets. When the control was put into "forward," the electromagnet associated with the forward cylinder would electrify and attract the end of the forward spring to it. That would stretch the spring out, which reduced its inside diameter enough to tightly engage it with the forward gear cylinder as well as the forward prop shaft cylinder, essentially making them operate as a single unit. That would turn the prop forward. When the control was put into "reverse" the electromagnet associated with the reverse cylinder would do the same. The problem I had was that somewhere in the wiring there was a short, so when I put the control in either forward or reverse, both of those electromagnets would be electrified simultaneously and the forward and/or reverse springs would break. I didn't know where the short was but decided to just replace all the wiring between the control box and the lower unit. And, obviously, I had to replace the broken springs as well. That fixed the problem. But I always thought it was a bad design.

[@stevanrose7439]

Omg 😱. I’m trying to get my gear ⚙️ box to work and it looks a lot like the cut away that he shows. I can’t imagine add springs and electric with wires to the mix. It’s always a adventure when I set out for the water.

[@garylewis327]

@@stevanrose7439 Yes, always an adventure. That's why they say the best days of a boat owner's life is the day he buys his boat, and the day he sells it. Lol.

[@tomharrell1954]

Aussie guy you are a lifesaver!! This is just what I needed. Good on you mate! I hope you have a great day

[@DangarMarine]

You're welcome mate. :)

[@elmerexpress]

Simple, yet very clear - a rare gift!

[@BMAN2065]

the best youtube outboard teacher

[@DangarMarine]

Thanks Brent!

[@elguaguero23]

Great video , very informative, I’m in the process of replacing the gears and seals on my 88 mercury 100 HP outboard , water got in it and destroyed the pinion and gears , had my boat for 13 years and kept in good shape , bought most of the seals and bearings but the gears set are very expensive here in the states and kind of hard to find given the year of the motor , thank you so much Sir for all your videos , I am a fan

[@stevendowdy8688]

Fantastic job of explaining how the gears work!!! Please keep up the KZbin series

[@mikespindor]

Thank you for the video. I have a Mercury Force 120 in Vancouver Canada. Never knew exactly how the gearbox worked. Appreciate you passing on the knowledge to people.

[@DangarMarine]

You're welcome Mike, glad the video helped you. :)

[@richwilson7017]

Nicely done on the dog clutch in and out explanations! Good job

[@1greghawk]

very informative for non mechanical minded people like myself. thank you

[@DangarMarine]

You're welcome, glad you liked it.

[@CorsicaSurveys]

Excellent video. Visuals are everything. Keep up the good work the people need it!

[@DangarMarine]

Thanks mate. :)

[@rudolfvanderven]

So much complicatedness at such great speeds/forces in such tiny spaces, it truly amazes me. Never even used an outboard engine myself but I'm in awe of these things.

[@DangarMarine]

They are amazing pieces of engineering, that's for sure.

[@markmarkw1919]

Excellent video! Definitely among the best I've seen; clear and concise without lots of superfluous chatter! The only possible criticism I can muster is that it would be nice to show the "cam" end of the shifter-shaft, to explain better what makes the dog gear move.

[@millbaymoll2420]

Very nicely done - straight forward explanation with a well made demo gear box . Two thumbs up.

[@DangarMarine]

Thanks mate. :)

[@erikweste]

Excellent work, this video cleared up a ton for me. Thank you for the clear and concise explanation.

[@DangarMarine]

Glad it was helpful!

[@ozskipper]

Love your channel mate.. I watch a lot of these and you just stick to topic and your info is so straight forward.. cheers.

[@DangarMarine]

Thanks mate, glad you've been enjoying the vids.

[@AlanMitchell-v6g]

Great cutaway; thanks for the excellent description of the gubbins!

[@MrGeorgeferreira]

Dangar, thank you so very much for taking the time to do this. very , very good video and explanation. love the way you showed how things work inside, really, really good. I have an outdrive, bravo iii and this was great to understand how it works. god bless.