How a two stroke outboard works.

How an outboard motor works. Just a quick look inside an outboard to see how things work. I have wanted to do this video for a while, hope it helps to visualize what’s going on inside an outboard. Cheers 👍👍👍

[@StefanZivkovicMedia]

Fantastic explanation with good repetition to emphasize the processes. Thank you. This should be way more popular.

[@25hpboatracerman]

Thanks so much for your comments mate. All the best Aussie Boat Guy 😊

[@mitchelldranow5069]

Best explanation for how a two stroke works on the internet.

[@25hpboatracerman]

Thanks mate 👌👌 I made that video because I really could not find one explaining it simply like that with the visual actual motor cut open. Really appreciate your comments mate. Cheers 🍻 Aussie Boat Guy 😎

[@douger1517]

Excellent vid showing how it’s works. I love how simple they are compared to four stroke.

[@nordicdust]

Thats why I love 2 stroke🙂 I understand them, 4 stroke are a bit over my head 🙂

[@25hpboatracerman]

Thanks mate 👍 I loved making that video. I do love two strokes, your right, so simple. If I did a video on a four stroke it would definitely be long. Cheers 🍻

[@cornfedful]

Incredible explanation and visual. Nice job!

[@25hpboatracerman]

Hi Mate, Thanks for your encouragement, had fun making that video. cheers 🍻 Aussie Boat Guy 😎

[@mitchelldranow5069]

Brilliant. I always wondered what reed valves do, amongst other two stroke components. Wonderful video. Well explained.

[@25hpboatracerman]

Thanks so much for your comments mate and glad the video is helping 👌 I had a fun time making it. Cheers 🍻

[@driving_in_YYC]

Great explanation. 👏

[@25hpboatracerman]

Hi Champion, I really appreciate your comments mate. That was a video I have wanted to put together for ages and was so much fun. Cheers 🍻 Aussie Boat Guy 😎

[@boneless4799]

Brilliant explaination

[@25hpboatracerman]

Thanks mate 👌 I really appreciate your comments. cheers 🍻 Aussie Boat Guy 😎

[@jimdrechsel3611]

⁠ that makes sense. The clear tube was also on the suction side and it was flowing. Couple days ago the water test was a success. The two leaking reed base gaskets were the problem. The boat hasn’t run this well for some time. I really feel the 3M 847 sealant placed on both sides of the reed base gaskets and the brown Evenrude/Johnson sealant on intake manifold gaskets provided an air tight seal. A tip someone else told me about timing helped too. Setting the idle timing 2 degrees advance on the trailer and rpm 1000 put the settings right on target when I checked them again on the water in gear. Thanks for the replies. I’ll be watching your channel.

[@25hpboatracerman]

Good news mate 👍 Hope you have happy boating for a long time now 😊 cheers 🍻 Aussie Boat Guy 😎

[@pikkolo47]

Great stuff!!

[@25hpboatracerman]

Thanks Champion 👍

[@darrylhenchie4765]

That was a great demo of the workings. Thanks mate.

[@25hpboatracerman]

Cheers mate, really appreciate it 👍. I had fun doing that video.

[@bradleyfarquhar2023]

great video mate that's a good example of how a outboard looks like from inside fantastic mate.

[@25hpboatracerman]

Cheers mate 👍 really appreciate it. I’ve been wanting to do that video for a while. 🍻

[@Adam-en4zm]

Very helpful for helping understand how these cool little machines work, thanks!

[@25hpboatracerman]

Cheers mate, Really appreciate your comments 👌 I also enjoyed making that video, been wanting to do that for a while. All the best Aussie Boat Guy 😎

[@florintancu9352]

That s a wonderful way to explain!!! Thank u!!!

[@25hpboatracerman]

Thank so much for your encouragement Cheers 🍻 Aussie Boat Guy 😎

[@nusaking4528]

Loved it 👏👍

[@25hpboatracerman]

Thank you 😊

[@philipleong4221]

Excellent explaination!

[@25hpboatracerman]

Glad it was helpful! cheers mate, I had fun making that video 👍👌

[@wilsnich02]

great video, well done

[@25hpboatracerman]

Cheers 👍

[@paulwharton1850]

Brilliant, brilliant ! I learnt a lot. Many thanks......all the way from London.

[@25hpboatracerman]

Awesome 😎 so glad it was helpful. Thanks for your comments mate, really appreciate it 👌👌

[@paulwharton1850]

@@25hpboatracerman I'm half way through watching your other video "Outboard Service Guide" - You explain everything so clearly - I'm learning a lot !

[@livingliferaw6959]

🔥🔥🔥👏so informative thanks

[@25hpboatracerman]

Glad it was helpful!👌

[@djfrass5008]

Best explain video

[@richardcollins304]

Good theory. I love outboards.

[@25hpboatracerman]

Cheers mate, Yeah, love outboards too 😁

[@daveherron4021]

Great video

[@25hpboatracerman]

Thanks mate, Really appreciate your comments. All the best Aussie Boat Guy 😎

[@antonypereira3853]

Brilliant thank you!

[@25hpboatracerman]

You're welcome! thanks mate cheers

[@davidg4139]

Awesome

[@25hpboatracerman]

Cheers mate 👌

[@Jose-su8fr]

Top man

[@25hpboatracerman]

Thanks for your supper Champion. Cheers 🍻 Aussie Boat Guy 😎

[@grahamdonaldson29]

Keen for you explain the use of Boysen reeds why are they used please

[@nordicdust]

Best explained video on how outboard works that I have seen, well done and thanks. When the air and fuel mixture starts getting sucked ind to the top of the cylinder, the Exhaust port is open, wil some off the air fuel mixture not escape of before the exhaust port is shut under the compression? Again a gret video :-)

[@25hpboatracerman]

Cheers mate, really appreciate it. Very good question and true the exhaust port is open but the way and angle that the fuel air mix is introduced to the combustion chamber most of it remains in the pot surprisingly. If much where to escape into the exhaust section there would be possible back firing or flames in the exhaust tuner which would be not great. Thanks again mate, all the best 👍

[@nordicdust]

@@25hpboatracerman That makes sense, thanks mate 🙂

[@edmaister5268]

Really cool video! I wonder if this is a Yamaha 3stroke engine. It would be nice to know what motor is.

[@25hpboatracerman]

Hi mate 👋 It’s a 5hp Tohatsu two stroke block, same as the Japan built 5hp. Cheers 🍻 Aussie Boat Guy 😎

[@jimdrechsel3611]

Another question if you don’t mind. I was trying to troubleshoot a possible fuel starvation problem when the engine would not rev up. I attached a small tank with plastic hose and ran the engine. I noticed the hose didn’t fill up all the way. The small tank had a 3/8 line to a clip on fitting. I used as large a fitting I could find. The motor is a 2 cycle Johnson 225. I saw constant flow but it wasn’t a complete hose fill while it ran as I watched. How would you determine if the pump was doing its job looking at the flow of gas through the clear hose? Thanks again for your replies.

[@25hpboatracerman]

Hi Mate, Interesting 🤔 keep in mind it’s just a diaphragm fuel pump and the flow will not be that fast like an electric fuel pump. Cheers 🍻 Aussie Boat Guy 😎

[@homeandfamilyservices2650]

Good demo. Would like someone to explain in greater detail how the electrics work

[@25hpboatracerman]

Hi mate, Thanks for your comments 👌 I will endeavor to do a video on that at some point. Cheers 🍻 Aussie Boat Guy 😎

[@_.R.F.X.L._]

When you port the intake port you port it all around? Ore only in the sparkplug direction and sides?

[@25hpboatracerman]

Hi mate, If you mean where the reed valves are, I just removed the casting shapes that were protruding into the port a lot. Cheers

[@randy1ization]

what reason would cause a 9.9 evinrude to have 70/80 psi of compression, and will start if you remove the carb and spray pre mix directly into the reed intake block.. .,the engine would not create enough vacuum to suck fuel into the engine, even if sprayed into the carb throat... I removed the head and the head gaskets looks great.., also removed the intake and the reed leaves look great... I then removed the powerhead and checked the cylinders and pistons,, the cylinder walls have no cross hatch pattern in them and look very smooth and glazed... . my plan is to replace the rings and hone the cylinders,, I checked the diamemeter of the cylinder and it is in spec...

[@25hpboatracerman]

HI mate, That motor should run with that compression. Did you do a carburetor overhaul? I would definitely start with that (videos on the channel). make sure to remove all jets, possibly the low speed jet is blocked. cheers 🍻 Aussie Boat Guy 😎

[@randy1ization]

@@25hpboatracerman yes I rebuilt it twice, cleaned it 3 times.,, I pulled the carb off and spun the motor over with my electric drill.,,.,. it was not pulling vacuum thru the reed plate,.,. nothing,, im wondering if it has a bad lower or upper crankcase seal. like I said, it didnt even have enough vacuum to pull fuel into the engine when I squirted it into the carb throat.. it would only start if I sprayed fuel directly into the intake.. I spun the flywheel clockwise, pretty fast, so it should have been pulsing vacuum . as far as the compression, that was my thought as well, that it should run with what it has,,

[@Diesr]

doesnt the 5hp have a lot of potential power cause its a 100cc watercooled 2 stroke (the limiting factor in my case is probably the rotating asembly being heavy)

[@25hpboatracerman]

Hi Mate, Yes you are correct 👌 I have only scratched the surface on that with the modified 5hp I made on the channel. the guys in Borneo are getting over 70kph out of them apparently. cheers 🍻 Aussie Boat Guy 😎

[@jimdrechsel3611]

Very useful. If a reed valve base gasket leaks could that cause a drop in crankcase pressure and allow water vapor to enter the cylinder? I would think that the lack of volume during the intake stroke would halt air flow to the cylinder and push air back out through the carburetor. I have a milky white substance pushing out two carbs in my 6 cylinder Johnson outboard. Two reed valve base gaskets have been leaking bad and air/fuel is pushing out the two carbs with bad reed gaskets. The air/fuel mixture has a milky white color. I enjoy your channel. Hope you can respond. Thank you

[@25hpboatracerman]

Hi Mate, Thanks for your comments 👍 Thats annoying about your Johnson outboard. I am not sure why the stuff coming out of your carbs is a milky colour except if your motor is running at high rpm and the weather is humid then possibly could mix with condensation being sucked through the carbs - side note : at the end of a long boat race one of my mates had ice formed on the external bodies of his carburetors. Anyway, a reed gasket leak is never good and will course a vacuum leak which can be catastrophic as it can cause that cylinder to run lean and blow. You would normally be able to feel the motor running roughly or not happily with a vacuum leak. You are correct in saying that the downward stroke will force air back out the intake. weirdly it won’t affect compression too much with a vacuum leak on the lower side of the pistons. I would sort the leaks and see how it goes after that, also do a compression test to see if any damage has occurred plus check plugs to see if any are wet with any water. Cheers 🍻 Aussie Boat Guy 😎

[@jimdrechsel3611]

@@25hpboatracerman Thank you for the quick response. I haven't been able to really use the boat above 2000 rpm and have just been trying to sort out problems. I hope no damage yet from the reed valve leaks. My compression has been good and equal in every cylinder. I plan on reassembly then testing again and was just picking your brains a bit. I think I had bad locktite for the reed base screws and the gaskets may not have been tight enough. I also put a tap through the threads this time to really get a good feel for tightness securing down the reed bases. If I work it out I will share it with you later. Thanks for the advice. i will check the plugs after I get it running. It runs idle and slow - just not able to get to full throttle above 2500 rpm. Cheers back to you.

[@jimdrechsel3611]

@@25hpboatracerman I just wanted to let you know how things went. Today I removed the reed bases and checked the plates. The carbon fiber reeds were fine. When I swapped the carbon reeds in apparently the gaskets did not seal well. Also the reed base screws even though they had thread lock didn't stay tight. I had purchased two of the six reed base gaskets on eBay. Those two on a separate order did not have the peel and stick gasket surface like the original other OEM 4 gaskets I used from a separate order. The two gaskets without sticky peel and stick surface pushed out of place and leaked badly. I didn't know this until I removed the carb silencer on the 1991 Johnson 225. Until. I was troubleshooting a separate bad spark issue. This reed gasket leakage caused two carbs spitting out a milky white spray fluid. I think it was milky white because the exhaust was not being pushed out properly during the intake stroke. It was easier to go back out the through the carb. The back exhaust pressure brought water vapor back through the intake port and into the crankcase. The water vapor in the crankcase was then pushed back out the carbs. Just my theory. I took no chances this time during reassembly placing 3M sealer on both sides of the reed gaskets when installing them. The reed base screws were cleaned and soaked in degreaser brake cleaner before reinstalling them with new Permatex Blue Loctite. I also, even though the manual said not to use sealant, put the Johnson brown gasket sealer you normally put on threads on the intake gaskets front and back to make sure there were no leaks this time even out through the intake manifold. After waiting all day for sealants and loctite to dry I started it and it ran great. In fact I picked up 500 rpms and had to readjust the throttle cable at the helm and motor enough to lower the throttle back down enough. The real test now is on the water but so far it looks good. Better than expected. I hope this helps others after reading this comment. Lesson - Make sure you use new thread lock and put high tack sealer on both sides of the reed base gaskets. Your 2 cycle video helped ma a great deal to figure out what could be causing the white spitting fluid. Thanks for sharing!

[@shreddykruger8324]

Rad🤙🤑

[@willknight1005]

Hey mate I've got 2006 18hp Tohatsu, do you reckon it's worth getting after market reed valves? Or is the any other mods worth doing? Excellent video 👍

[@25hpboatracerman]

Cheers mate, The 18hp tohatsu is an awesome motor 👍. We have tried racing reeds in the 18hp and also the 25 - 30hp and found no real difference over the stock reeds which was surprising. Shaving the head to increase compression definitely gives more torque but not really any top speed gains I’ve found. I just leave my 18hp motors stock now, the tiny gains you get are not worth it. If you have the 15hp super Mercury (Japan built) I do like to put the 18hp cam on the stator to get full throttle from the carburetor. Thanks 👍

[@willknight1005]

@@25hpboatracerman Thanks mate 👍 It's a proper Tohatsu 18hp and she's Bullet proof! Maybe I'll play around with prop pitch. Also what do think about fuel/oil mixture?

[@25hpboatracerman]

@@willknight1005 Yeah awesome 😎 If it’s on a light boat and your after more top end speed engine height and prop selection are the ticket for sure. One of the boats at where I used to race power boats was getting about 82kph out of the 18hp. Keep in mind that was on a carbon wing boat (about 25kgs) with a very light person driving, nose cone and a 16 pitch through hub cleaver propeller, they only carried enough fuel onboard to complete one race at a time (about 600ml). I’ve seen about 65kph with a 18hp, shaved head and a 12p semi surfacing propeller on a tinny, not that pleasant to drive though. The 18hp normally hits about 50kph on a tinny which is pretty respectable too. 👍👍

[@willknight1005]

@@25hpboatracerman Cheers for the knowledge mate! She's on a 3m Stessl rat pack 👌 I only use it to get to my fishing/crab spots quick 👍

[@25hpboatracerman]

@@willknight1005 😂 Of course it is on a rat pack, perfect 👌 Well that is a pretty good setup mate, had the same for a while and was very happy. 👍👍👍

[@randy1ization]

also im thinking that two strokes , unlike 4 strokes require more vacuum to be able to run, because they have to generate enough vacuum to open the reed valves, and then create enough vacuum thru the carburetors venturi to pull fuel vapor into the cylinder.. where as in a 4 stroke, this is not the case..

[@25hpboatracerman]

Hi Mate, The reeds do function very easily with the volume that sis pulled through the motor. Keep in mind that your 9.9hp Johnson (if the early model) is about 216cc every revolution. Cheers 🍻 Aussie Boat Guy 😎

[@randy1ization]

@@25hpboatracerman the carb im working on is the hermaphrodite style carbs that came on the 92 evinrude 9.9 with the plastic bowl, top, and the weird nozzle jet set up .. not sure exactly how they work, and cant find any technical info on them., this is the 3rd carb like this ive ran across and all of the well jets have cracks in them..

[@DonziGT230]

Do you know why medium/large 2 stroke outboards use the variable ignition timing as a power control when no other engine is set up like this?

[@25hpboatracerman]

Hi mate, Yep 👍 Most outboards from about 6hp and larger use a stator to advance and retard the timing at the same time the carburetor opens. It is mostly for the lower rpm range and idle. Fixed timing two stroke outboards (normally 5hp and smaller) timing is set reasonably advanced to produce the peak power at full throttle but that robs power from the lower rpm range and most of the time will make the idle not as smooth. An outboard with a stator that has a more retarded setting at idle and advances during throttle will have a smother operation with better low and mid power. Also, a larger outboard will still run if you fix the timing at full advance on the stator but will lose mod range performance and will idle roughly, top end will be the same once the motor reaches the correct rpm. hope this helps. cheers 🍻 Aussie Boat Guy 😎

[@DonziGT230]

@@25hpboatracerman What's really strange to me is that outboards use the timing advance as the primary power increase up to about 1/2 throttle, then the carburetors start to open progressively more, no other engine works like this. Many two strokes I've worked on have fixed timing or timing that advances as the RPM increases like most 4 stroke engines do. There's obviously a reason for it since all the manufacturers do it, it's just strange to me.

[@homeandfamilyservices2650]

Anybody tell me what that partly rusted green disc is and how to get it off (without a fly wheel pulley if oiss). Thanks

[@25hpboatracerman]

Hi mate, If your talking about the flywheel then you can watch my 9.8hp tear down video a few vids back, I show how to get the flywheel off without a puller. Cheers 🍻 Aussie Boat Guy 😎

[@Diesr]

This looks like a tohatsu/mercury 5hp engine is it possible to up the compression by changing a piston and are there aftermaket pistons for this engine cause I’ve noticed mine isnt making power but it will rev also is there a hemi piston possible in 2 strokes?

[@25hpboatracerman]

Hi mate, Yep Tohatsu- Mercury Firstly if your one is not running right, I would do a carburetor overhaul and check compression. On the modified note: I have put up a few videos on modifying a five hp, I shaved the head, bigger carb, ported the block, modified the gearcase and put a racing prop on, about 100hrs work for another 15kph. For me it was worth it to answer my question of - wonder how much speed I can get out of a 5 🤷‍♂️ Cheers 🍻 Aussie Boat Guy 😎

[@Diesr]

ive checked carb its fine it has a plug in the idle jet for some reason (idk if its idle jet might be a trough hole for vaporizer) i dont have a compression gauge but i think it needs a rebuild cuz its been in the garden for a while and it doesnt get to the power band i think cuz it wont go on plane on a fairly light boat

[@25hpboatracerman]

@@Diesr Hi mate, Yep they need the plug in the idle jet, it draws fuel from another place. Yes, the 5hp are not that powerful to start with, mostly don’t get any boat on the plane. Cheers 🍻 Aussie Boat Guy 😎

[@mohabayd2107]

What makes the motor spin in the first time like before the air gets pressed in the top by the piston

[@25hpboatracerman]

Hi mate, Either a pull starter or electric start. The motor needs to be manually spun initially to get the whole system working. Like when you turn your key in a car, it gets a small electric motor to spin the motor initially. A pull start just like on a lawn mower or brush cutter. Hope this helps, Cheers, Aussie Boat Guy 😎

[@mohabayd2107]

@@25hpboatracerman Ohh so that's why they pull that wire on the motor its to get it initially started thank you for the knowledge 🔥🔥🌟🌟💪🏽

[@xaviersoares8530]

Xavier Soares I want water pump part

[@25hpboatracerman]

Hi mate, Will try to do a video on that 👌 Cheers Aussie Boat Guy 😎

[@StephenWest-xm3uv]

Can you tell me if water would get into the motor if at the base plate there is a gap in the gasket between water jacket and the exhaust chamber.? 4:29

[@25hpboatracerman]

Hi, Yep, if a gasket fails on the exhaust jacket or the head gasket fails water will get into the combustion chamber. Cheers Aussie Boat Guy 😎

[@StephenWest-xm3uv]

Thanks for the feedback have you got a email address I’d like to send some photos of the problem I have.?

[@StephenWest-xm3uv]

Hay mate i know you’re real busy, but I have been ripped off by a boat company that has done a bad repair on my Yamaha 50 out board the motor has gotten water into it and is now seized they say water can’t get into the motor from we’re it doesn’t seal at the base gasket.? So now I have to research and have information to take the business to the ACCC for warranty.! So mate if you can help out I would be really grateful.!!

[@loyauolivier533]

What would be the engine brand and model in that video?

[@25hpboatracerman]

Hey mate, The motor I used in this video is a 5hp Mercury - Tohatsu block. Cheers 👍

[@loyauolivier533]

@@25hpboatracerman thanks

[@aidencronje736]

what motor is this block from? is it a yahmha 4hp

[@25hpboatracerman]

It’s a 5hp Mercury (Japan built by Tohatsu) Cheers Aussie Boat Guy 👌👌

[@aidencronje736]

@@25hpboatracerman thanks this helps alot i am upgrading my merc 4hp 2stroke to a 5hp

[@ct1762]

the slower a 2 stroke spins, the more fuel/air escapes out the exhaust port/s. conversely, the faster the more efficient. a directly - injected 2 stroke solves this at the expense of complexity. interesting to note: at full throttle a 4 stroke burns the same amount of fuel everything equal

[@25hpboatracerman]

Thanks for your input mate, yeah, the direct injection two strokes are pretty good on fuel compared. Do you mean that four strokes burn the same as a two stroke at full throttle per combustion stroke? Cheers 🍻 Aussie Boat Guy 😎

[@fullblownredneck9623]

Not enough views for the crucial information explained. Guess there's a reason why marine mechanics are busy.

[@25hpboatracerman]

Cheers mate 👍

[@julescorten4368]

How much hp was that engine

[@25hpboatracerman]

Hi Mate, that is a 5hp. cheers 🍻 Aussie Boat Guy 😎

[@freakazoid111]

I have a 2 stroke 15 hp mercury. I was doing a flush test but the prop nut was only on hand tight. Is this ok?

[@25hpboatracerman]

Hi mate, The prop nuts don’t need to be super tight, just on firmly, hand tight is definitely not enough. Make sure if it’s the 15hp USA built that the nylon locking part of the nut is still firm and new (designed to stop the nut undoing during operation) if it’s the 15hp Japan built with the castle nut, make sure you use a split pin to lock the nut in position. Lag thing you want is to loose your prop while out on the water 🤦‍♂️ Cheers 🍻

[@freakazoid111]

@@25hpboatracerman Thanks. So it isn't going to cause water to get in where it shouldn't if the nut is loose? Also I have noticed a small amount of black oil has leaked out from the small hole at the bottom of the unit. I'm hoping it's just burnt fuel residue.

[@25hpboatracerman]

@@freakazoid111 Yeah, pretty normal to have the black oil, it is normally un-burnt oil. If it’s gear case lube then you will be able to smell it, gearcase oil stinks, un-burnt two stroke oil isn’t very smelly. Just make sure the prop nut cannot undo by itself. Cheers 🍻

[@freakazoid111]

@@25hpboatracerman Thanks for the quick replies and they are helpful. I am new to it all and have lots of questions, I guess I could also check the oil / colour with the drain screw at the bottom. Any idea what the thin pvc tubes are at the back / bottom of an rib? they are glued on to pipes that are essentially holes in the back / bottom of the boat. and the tubes are floppy & about 60mm diameter / 2 feet long. I'm guessing they are some kind of one way drain tubes that let water out of the boat and not in?

[@25hpboatracerman]

@@freakazoid111 Too easy mate 👍 Yep, one way drains, you nailed it 👌

[@cheba4786]

Tohatsu 5?😁

[@25hpboatracerman]

Hi Mate, Yep, you got it 👍 cheers 🍻 Aussie Boat Guy 😎

[@besearchingforwisdom6267]

Wrong. Really wrong... the description of the strokes are not right You really missed it, and, at this point, every comment has missed the errors and the video should be removed and trashed and redone correctly

[@25hpboatracerman]

Hi mate. Thanks for your opinions. Are you going to say what’s wrong with it? A two stroke is actually pretty simple and from all I have studied and from hands on experience the video is very correct, in saying that I am happy to be corrected if you can tell me what is wrong with the explanation. Cheers 🍻

[@besearchingforwisdom6267]

@@25hpboatracerman Sure thing, I'll start with a summary of the description of the 2 stroke, and then reference the video for your time stamp and describe the strokes. The 2 stroke engine has all 4 "events" occurring in 360° of crankshaft rotation, (instead of occuring in 720° of crankshaft rotation as in the 4 stroke engine)... that is: SUCK = intake SQUEEZE = compress... (1:59 and again at 3:18) BANG = power (the good part)(2:10) BLOW. = exhaust and repeat in that order at very high speed. - The first stroke (intake or " Suck) occurs when the intake port is exposed near the bottom of the piston travel and is finished when the same port is closed during the upward travel... transitioning to the ~ - Compression stroke (squeeze) is the duration of the piston travel to the "top" of the chamber in the cylinder, and then ~ - the "Power" stroke (Bang) begins at the point of ignition (ie ignition timing 10° before top dead center), forcing the piston to travel down (the fun part), and then ~ - the Exhaust stroke (Blow) begins when that port is exposed during the downward travel and is continued when the intake stroke is replacing the spent exhaust with good air mixed charge to repeat.. I'll review the video and add the time stamps and edit that in. Cheers to you too Each of the "Events" as I've described, occurs in the combustion chamber side of the piston And The intake system that you are focused on in the video occurs in the underneath side of the piston, or "Down under" (up to the 4th minute in) and the attention you give to that operation is correct and proof that I'm not living in the land down under and focused on the topside of the engines operation and I spoke before finishing your very good video. Two thumbs up

[@25hpboatracerman]

@@besearchingforwisdom6267 Got there in the end 👍 Cheers

[@chrispeterson1247]

"fuulee er mixtcha"

[@25hpboatracerman]

Hi mate, not sure if what you are saying? Cheers 🍻 Aussie Boat Guy 😎