Mercury 15hp carburetor overhaul

[@jeremywatson3194]

Big thanks. This is the exact 2 stroke i needed to clean. Was filthy and not running. Cleaned it as per your video, spot on now. Cheers mate.👍

[@25hpboatracerman]

Hi mate, That’s great news 👍 Glad the video helped and appreciated your comments champion. All the best, Aussie Boat Guy 😎

[@gandrewboyd]

Your videos and your presentation of material is first rate-thank you! I’m a videographer and video editor and know how much work these videos are. You’re helping me a ton with my old Nissan NS18C. 👍🏻👍🏻

[@25hpboatracerman]

Hi mate, Thank you so much for your kind words 😊. I just really like boats and outboards and enjoy sharing, hoping it helps others and it seems to be doing that which is awesome 👏 Unfortunately I don’t have the best camera gear or editing stuff but you are correct it still takes a long time. The 29 min video I uploaded the other day, wow I nearly could not get through editing 😂. Thanks again and all the best, Aussie Boat Guy 😎

[@danielpage64]

Awesome mate Great step by step and great camera work to see everything made it so simple 👍👍👍

[@25hpboatracerman]

Thanks mate, So glad it helped. All the best, Aussie Boat Guy 😎

[@davidjackson7788]

Thanks best carb cleaning clip yet 😊

[@25hpboatracerman]

Cheers mate 👍 Really appreciate your feedback and support. All the best, Aussie Boat Guy 😎

[@bulaKurt]

Really great video !! Nicely done and very informative thanks heaps !

[@25hpboatracerman]

Glad it was helpful Champ 👍

[@stevo3644]

Thanks so much for making and sharing this video. The tuning part at the end of the video was exactly what I was looking for. 👍💪

[@25hpboatracerman]

Thank you so much for your comments mate 😊 That’s exactly why I make these videos. Cheers 🍻 Aussie Boat Guy 😎

[@shanewilkens1089]

completed the overhaul, started motor and it run really well until the fuel run out, i had to manually pump and it run again, did this several times and cannot fix the problem. I have replaced the fuel line and hand pump and cleaned out the fuel tank. where to now, please assist. Motor is exactly same as yours.

[@rikkwakeupwesternworld9874]

Excellent ,I have the same outboard on a 3.2 metre X commercial flat bottom tinny made from 3mm ally. Goes like a scalded cat with this motor, originally tried an Evinrude 7.5 hp even that went well. All your videos well presented and informative A+++

[@25hpboatracerman]

Thanks mate, Yeah, I love the 15hp merc super (18hp Tohatsu). Wow, 3mm thick, that’s awesome 😎 nice and strong and I bet it’s stable being a flat bottom. Cheers 👌👌👌

[@jamaltalib5774]

terima kasih atas tunjuk ajar step by step

[@willknight1005]

This helps me a lot 👍 much appreciated 👍

[@25hpboatracerman]

Too easy mate 👍. Glad it’s helpful, pretty easy once you see it done. A few people have requested this vid. Cheers 🍻

[@random_dude_99]

Stupid question but anyway, can a bad headgasket cause my outboard to not run without the choke and not idle?

[@25hpboatracerman]

Hi Champ, Not a stupid question at all. Probably a carb problem, you need to remove the idle jet and re-clean for starters. A bad head gasket can cause running issues if it’s allowing water to spray into the combustion chamber. Normally will run bad through the whole rev range. Cheers 🍻 Aussie Boat Guy 😎

[@random_dude_99]

@25hpboatracerman Thanks! I cleaned the carb and everything. I will order a headgasket and the o-ring that goes on the intake. I also noticed that the little rubber plug on the top of the carb was missing so i added one(i saw it from your carb overhaul video) Do you think that it could affect the way it runs?

[@nazrin5705]

thank.. you solve my problem.. thank 😊

[@25hpboatracerman]

You're welcome mate, happy to help! Cheers 🍻

[@timlorenz9936]

This was a really good detail.

[@25hpboatracerman]

Cheers mate, hope it helped 👍.

[@tompitchford1260]

I have this same engine. It was idling rough and cutting out at 100% throttle. After a carby clean she’s running perfect 👌🏻 thanks

[@25hpboatracerman]

Too easy mate 👍. Glad your motor is working well again 👌 Really appreciate you taking the time to comment. Cheers

[@stuartthompson8837]

Mines doing the same thing, cuts out at full throttle. Going to rip it apart now.

[@25hpboatracerman]

@@stuartthompson8837 Probably some junk getting in the high speed jet. Good luck 👍

[@Shorts365-b2w]

Nicely done.

[@25hpboatracerman]

Thanks mate 👌 hope it was helpful

[@raminoman9459]

Thanks very much.

[@25hpboatracerman]

Glad it helped mate 👌 All the best Aussie Boat Guy 😎

[@bunndyboy]

Yet another awesome vid ,the best on KZbin. I have a question.. I have a 15hp super, made in Japan. What service manual should I be looking for ? Mercury or tohatsu ? I'm in Australia and can't find anything Mercury its all the American model

[@25hpboatracerman]

Hi Mate, Thanks 🙏 really appreciate your comments. You can use the 18hp Tohatsu manual but it probably won’t be much help as it’s normally not an instructional book these days.. Cheers Aussie Boat Guy 😎

[@bunndyboy]

I got a mercury one from American but the jap 9.9/15/18 service manual. It's about 16mm thick so plenty of information. I wanted to show you a pic but I can't work out how to do it lol

[@Sailaboat]

Love the channel bud. I have the same engine but recently its started missing under load. With just me aboars it will plane ok but has a slight miss at top rpm. With 4 people aboard it wont even reach half rpm and it is missing badly. I checked the plugs, one was wet and the other dry. Think its the coil assembly but changed the plugs because i had some with me. No change after replacing the plugs. I did also notice that the top plug lead was not sitting in its holder ( little metal bracket )and may have been flopping about for some time.. Have you come across this before.. Carby has been off / cleaned but im pretty sure its not a fuel issue. Thanks in advance..👌👌

[@25hpboatracerman]

Hi Champion, From your description it sounds like a spark issue. Could be a pickup coil but most likely the power pack. Is there a way to try a second hand one, it’s a case of trial and error when chasing an issue like that unfortunately. Cheers 🍻 Aussie Boat Guy 😎

[@Sailaboat]

@@25hpboatracerman thanks. I managed to find a spare coil pack off a freind and it didn't change. Since then it's gotten worse and can't even rev it pass qtr throttle without it missing. So I'm thinking it's either the pick-up ( like you said )or the cdi module I did also notice some sticky fluid underneath the cdi where the wires come out of the cdi module itself. Cheers for the info 👌

[@Ta-sn6vc]

Thanks for the video , i have same engine notes the butterfly will not open full when full throttel? Any idea

[@25hpboatracerman]

Glad the video helped mate. Yes the 15hp super is actually an 18hp but with less timing and the carb is restricted. if you want your carburetor to fully open you need to purchase the 18hp throttle cam and install that. Cheers 🍻 Aussie Boat Guy 😎

[@Mikey_Neuman]

hey mate great viedo just wondering how i would push more power out of a 15 like yours would i have to drill the jets out or install a 25hp jet ? if you have any tips let me know thanks mate

[@25hpboatracerman]

Hi Mate, Definitely do not play with jets, they are very specific to the carburetor throat size. The only reason to play with jets is if the air-fuel mixture is to lean or to rich. If you make the jets larger you will loose speed. To get more power, you can buy the 18hp throttle cam and advance the timing slightly but you will gain 3hp which may not be too noticeable. you could modify the head and make a high compression head too. Cheers 🍻 Aussie Boat Guy 😎

[@Mikey_Neuman]

@@25hpboatracerman hey mate thanks for all that i just had a thought of drilling the jets out but i probably will just put 18 hp jets and then advance the timing. Is that a specific way to advance the timing? i have also orderd a velocity stack which should increase some airflow

[@NathanPower-d6f]

Thanks mate… fixed my issues 👍 yeeeew 👍

[@25hpboatracerman]

Awesome job mate 👌👌

[@ttoobs8871]

Great video 👍

[@25hpboatracerman]

Cheers mate 👌😎

[@aidencronje3458]

Hi mate do these motors have shallow mode if so how do you get it in shallow mode I got one but can’t seem to figure out how to do it

[@25hpboatracerman]

Hi Mate, Yes they do. Flip the tilt handle on the back of the motor downwards and lift the motor 1/2 way and lower it back onto the shallow drive setting. If this is not working then the shallow water drive bracket may be not freely moving. You will need to free it and grease it, they often get salt build up where they mount. Cheers 🍻 Aussie Boat Guy 😎

[@Mikey_Neuman]

@@25hpboatracermando you have a viedo on how to do this

[@davidcastano7009]

Hola que número de chicle lleva el 15hp

[@25hpboatracerman]

Hola, Es un bicilíndrico y la presión ronda los 140 psi. gracias, Chico del barco australiano 😎

[@yelvos4501]

Got a near new one of these, just started running a bit rich, Smokey/oily. Plugs are wet after a run, 50:1 Penrite low smoke oil and premium unleaded mix. Could it just be a slight air/fuel mix adjustment to sort that out?

[@25hpboatracerman]

They do smoke and plugs are pretty wet (with fuel oil) when running at low rpm’s. From factory the idle settings are pretty rich but it needs to be and there is a good reason. If you lean out the idle and low speed settings the rev range gets a big flat spot. Also, they do drip dirty un-burnt two stroke out of the prop when stored, don’t worry, totally normal for those. great motors, one of my favorites and strong. Cheers 🍻 Aussie Boat Guy 😎

[@IrfanHai]

Very helpful.

[@25hpboatracerman]

Cheers mate 👌 Glad it helped 😊

[@aboyFinn]

I have cleaned and re-installed carb and it 'almost' runs fine. My top end seems a bit slower but if I use about a half of choke, I get more power and speed. What adjustment might I make on the carb to get this without using the choke knob? Thanks in advance.

[@25hpboatracerman]

Hi mate, That’s frustrating 🤦‍♂️ I would do another carb overhaul strait away. If it’s idling fine then it sounds like something in the high speed jet or the emulsion tube or the fuel passages around the high speed circuit. Check all your fuel lines too by squeezing your fuel primer bulb really hard (when connected to the motor - carb on) and look for any fuel drips at the fuel lines or connections. Make sure when you do the carb overhaul to blow out all the fuel galleries. When the top plate is off the carb as well make sure fuel flows down the two holes back down to the main and low speed jet. I have been doing carb overhauls basically my whole life and with some motors I still have to re-do an overhaul as there may have been some junk in a line somewhere or (unfortunately) I’ve missed something that I could not see in a gallery or passage) Also had some carbs that don’t seem to want to work anymore as well which is incredibly frustrating. Wow, that’s a lot of word’s 😂 Anyway, do another carb overhaul, following the vid, with carb cleaner solvent and let me know. Cheers 🍻 Aussie Boat Guy 😎

[@bradleyfarquhar2023]

good vid mate

[@25hpboatracerman]

Cheers mate 👍 Hope it helps some people out. 👍👍👍

[@willknight1005]

Hey mate do you have a pet parrot? I've got two conures and they're noisy as!

[@25hpboatracerman]

😂 nu, just some birds out the front that love being really loud when I try to take a video. There are some Indian minors and also lorikeets. Cheers 🍻

[@nordicdust]

Yeah :-) Thanks

[@25hpboatracerman]

No problem mate 👍

[@GuillermoJGasperi]

What year is that outboard? I have a 2006

[@25hpboatracerman]

Hi mate, I cannot remember the exact year but it would be around 2006 like your one. Cheers 🍻 Aussie Boat Guy 😎

[@mathewoutram441]

I have a 18hp tohatsu, 2nd one I love them. I’ve had recent multi level fusion and would like to know my options for electric start and power tilt/trim before I am forced to sell this. Any suggestions?

[@25hpboatracerman]

Hey mate, Sorry to hear about your fusions, that sux but I hope it helps in the end. Yeah, the 18hp is absolutely golden. Electric start is no problem, you can buy a full kit or even get the parts needed from a wrecker. The easiest option for trim and tilt is a CMC trim unit that is separate to the motor, not cheap but I have heard they work well. Kind regards Aussie Boat Guy

[@mathewoutram441]

@@25hpboatracerman thanks a lot mate I’ll have a look 😎

[@florianziu3648]

Ciao. Mi può dire la miscela giusta per questo motore? Quanto olio si mette per 1L di benzina?

[@25hpboatracerman]

Hi mate, I use 50 to 1 So 50 parts fuel to 1 part oil. So every 1L of fuel I use 50ml of oil.

[@florianziu3648]

@@25hpboatracerman Thank you

[@florianziu3648]

Scusami, mi puoi dire il codice della candela che monta questo motore?

[@nordicdust]

That runs pretty smooth :-) Not quite the same carburetor as on mine, but same principle:-) My outboard is a European/Belgium model (Are they mede in Japan?) 2002 Mercury Outboard 15 [M] [ 1015201ZB ] I find that a lot of two stroke shake from side to side when they idle. Any tips on how to fix that. Great video, you are my new best freind ;-)

[@25hpboatracerman]

Cheers mate, Yeah right, would be interested to see the differences in your carburetor, your correct that most of the carbies on outboards are the same principle. Definitely the two stroke outboards can have a rough idle, especially when in the water and in gear. Sometimes it’s not possible to tune this out. It can be caused by the motor ingesting it’s own exhaust fumes at low speed or even that the idle timing is not spot on and of course tuning. Definitely tuning the outboard when you are out in the boat is the best bet. I have a 15m Mercury 2008 model and when on the water it does not have a smooth idle regardless of what I tried, awesome little motor though. Thanks again 👍

[@danielecorso8018]

Hi mate my M15D2 tohastu has a decent kick to it when engaging into forward gear is this normal ? And the throttle arm is turned to the lowest speed next to nothing

[@25hpboatracerman]

@@danielecorso8018 Hey mate, your idle speed may be set a little high. Try lowering your idle speed (it should be low but not low enough to stall when you put it into gear). Keep me posted 👍

[@25hpboatracerman]

@@danielecorso8018 Make sure your lowering your idle speed screw not your idle mixture screw. Cheers 🍻

[@Jorge-oj7hd]

what's the difference between this and the mercury 15 "super"? Is this also 18hp? Thanks

[@25hpboatracerman]

That is the Mercury 15 super. It is the same block as the 18hp tohatsu but the carburetor doesn’t open as far. You can change the cam on the stator that opens the carburetor butterfly to the 18hp one then it is 18hp. Really not a massive difference to tell the truth. I have a video comparing blocks etc if you are interested on 9.9 - 15 - 18hp. Cheers 🍻

[@Jorge-oj7hd]

Thank you.

[@gutaoberaba]

The cam of stator, and the carburator, venturi of 15 Mercuy super have 20mm diameter of venturi, and 18 Tohatsu 22mm, and gigleurs of 15hp are 80 and 110 anda in 18 60 and 116 . Sory for the english, but in Brazil, these 2 strokes are the most outboard sale.

[@Jorge-oj7hd]

@@gutaoberaba Fala, Guto. Tenho um Mercury 15 igual ao do vídeo. Será que vale a pena transformar em 18? diminui a vida util? gasta muito combustivel? Vlw

[@25hpboatracerman]

@@gutaoberaba Nice 👍

[@CaptMarkSVAlcina]

Thanks for the great video but I don’t think I would be Cleaning it with a Metal screw driver in petrol.

[@25hpboatracerman]

Cheers mate 👍. Fair enough.