How To Adjust A Mercury 2-Stroke Carburetor 6 8 9.9 15 HP 1989-2006

How To Adjust A Mercury 2-Stroke Carburetor 6 8 9.9 15 HP 1989-2006

[@lawrencebutler2423]

Searched for an hour among many unhelpful videos. This was so spot on and to the point. Thanks for the help!

[@bryanchapman6164]

Just what I needed for my task at hand. Nice job showing multiple adjustment points. Most other videos I watched on adjusting the lean/rich mixture were very vague about starting points and tips for making slow, incremental tweaks. Thank you so much for posting this. Very timely.

[@LanDanGle]

Man this video just helped me tune my 2000 mercury 15 I really appreciate the information! My issue was the high idle parts were stuck and the airfuel

[@kyleherber3231]

absoluetly great video helped me fix my 15hp mariner even my dad couldn't fix! thank you! just in time for my fishing trip this weekend

[@Boaters_hub]

Thankyou Thankyou Thankyou! For taking the time for making these videos and really going into detail on how to do such adjustments and repairs. I am having issues and i am going to attempt to rebuild the carb as its flooding. Than id like to dial it in once rebuilt

[@KevinPaulineNeal]

Hey. Glad I found you. A great help. Thanks from New Zealand.

[@brianross4388]

A million thanks! Was at friend's place with a new-to-him 2002 Merc 9.9 which was running like crap. Watched your video, tuned per your instructions, and it now runs like a top! Very excited to see your timing video. And potentially links to a battery-powered timing light.

[@mathewforsyth1006]

Thanks from NZ Martin. Your videos are clear, give confidence and are a pleasure to watch. All the best!

[@vancemoncrief3389]

I would like to see a on how to adjust the reverse and forward linkage on my 15 horsepower 2003 tiller steering Mercury motor. And thanks for sharing your videos I rebuilt my carburetor from watching your videos thanks.

[@terencemckibben2330]

Fantastically helpful vid. Thankyou

[@TheMrChill_tv]

Hello, first of all thanks for all the quality videos, I was rebuilding my engine that is pretty similar to yours, mine is a Mariner 13.5hp 2 stroke.. this week I'll follow the videos after watching it 20 times!! Hope everything goes well.. I had one more trouble and cannot find anything yet so I write it here and maybe you can make a video to help us! I'm not able to put reverse, the cables looks good, and forward, neutral and the gas works well, I wanted to take all the cables out, put some grease there and adjust the cables but I'm not sure how to do it.. I use the manual controls to move the engine.. I'm from Spain, I don't know some words but I hope that someone could help me.. thanks you!

[@666dynomax]

this is a really great detailed vid... my '05 merc 25hp 2s is hard to start, i'm going to start with this.... im hoping that first adjustment is what might be wrong,, starts all day one pull after its warm

[@ct1762]

make sure the primer is really working well. simply loosen the carb mounting nuts and pull it forward and hit the primer. should be squirting into the crank case, not dribbling. turn your low speed needle out 1/4 turn if its really hard to start. beyond that, ignition and timing check is in order

[@leemcminn4978]

I hope you're still checking these messages. I've got an older Mercury 8 HP 2 stroke. I cannot get it to run for any extended period of time without pulling the choke on. I've tried adjusting the carburetor using the steps in this video. Even after keeping it running after 10 or 15 minutes, I have to pull the choke on to keep it running. I pull in on and turn it right back off and it'll run for a couple of minutes, then I have to repeat. If I put it in gear, I basically have to keep the chole on to keep it running. This really sounds like a mixture problem, but I'm not a mechanic. Not sure what else to try. I' haven't checked to see if it has a thermostat yet.

[@STIowner1]

Have you rebuilt your carburetor? Mine was doing the same thing and I rebuilt the carburetor using a sierra marine kit. And it’s running smooth now

[@alexandreduval2763]

Hello, i did follow steps in the video and it works perfectly now, big thanks and very clear and helpful comments, now everything looks working well, to motor runs like a baby :), the water going out to the motor is maybe to hot from my point of view, question what temperature going out should be and if too hot what should i do to cooling the water temp down. (Note i did change the pump propellor. Thanks

[@user-sk9yc5px5r]

I’ll have to try it tomorrow but this may of just solved my problem were my motor won’t start unless I take the cover off and give it some throttle by hand but maybe if I tighten that screw in the throttle it’ll start on its own now?

[@acussageonline]

Hi Sterling, thank you for these awesome videos, really appreciate your teaching! I have this 1993 8hp, it has only 20 hours on it, but sits in garage for 20 years, it took 75 pulls to started wry first time, I cleaned the carb, still has difficulty when cold start, I tried to adjust it but find out it’s different than this video showed, it doesn’t has the idle screw like yours 😢

[@alexanders6248]

Is there a next video showing how to adjust the timing?

[@welltog]

Hi Thank you for all your video's from Anglesey Wales

[@jbatt6088]

Excellent explanation. I've definitely got a masters degree by now from KZbin University.

[@aaronr1328]

Hey man , awesome idea for that motor would be the sprung carb and ignition cable bracket . You know the 2 piece part in halves that the throttle push and pull cable drives .. . I could use it I know that

[@gs12please]

Thank you, sir! I'm back on the water.

[@giannanto1003]

I look you from italy best video!! Thank

[@Sveaisland]

Excellent video . Thank you

[@grindstone40]

Hi rebuilt the carb folllowing your great video. When I pump the bulb now fuel enters the carb body until the bulb goes hard. Stops then. Engine starts then dies any ideas?

[@murraydagenais8597]

Hi there. I have a 15hp mercury 2 stroke. I’m missing the #37 screw. It’s the M5 x 30mm screw with a jam nut. Could you tell me what the adjustment is supposed to be on that screw? Engine seems to be running fine with out. Just want to get it back in there so it’s fixed properly

[@mikeingeorgia1]

Thanks for the informative video!

[@chrisdarcyburt]

This helped me a lot. Thanks!

[@mugsymydog]

Would it be possible to do a timing video for the 6Hp. Thanks for your help in advance.

[@MCRC71]

Excellent! Thank you!

[@sammyrothrock6981]

Thank you for the video mine is a 7.5 and the carb is very different and I have a CDI solid-state so timing isn't adjustable... 🤔

[@jjr694]

Great videos by the way. Very helpful. Question.... I have a 2005 9.9 hp 2 stroke Merc. My carb rebuild kit comes with a gasket for between the carb and the engine block. When I took the carb off, there was no gasket. The aluminum mating face has a rubber seal built into the mating face of the engine side. The Mere parts diagram shows that there's a gasket suppose to be there. I had a mechanic friend says no gasket goes there, and another mechanic friend says that there is suppose to be a gasket there. So do i put the gasket there? Any advice would be appreciated.

[@seanlutzi2911]

I have what believe is a decent tuned motor exactly like the one in your video, 8HP 2 smoke, but im getting milky snot from the exhaust port, is this normal some say yes and then some say not so much, im using Lucas synthetic oil (15oz for 6 gallon can) brand new carb rebuild and accel pump. lil smoke not too much but some beige milky goop from the exhaust... any help would be great thanks, great vid! subscribed

[@bobbyschantz5905]

Hey Martin, your video on cleaning a carb was super helpful for me. I just cleaned mine and put it back together, but I'm still having problems. My gasket/diaphram that primes the carb (not sure of the actual name) was rotted, and i was hoping that was my problem. It would actually spray and leak fuel when primed. That is now fixe. But now when I start my motor, it runs rough at idle and will die unless the prime is fully pulled out. Not sure what the problem is. I tried adjustment the fuel mixture pin on the carb, but it didn't seem to help any.

[@martinmarine529]

May want to try a different gas tank Or it could possibly be the fuel pump

[@azimazman111]

my 1988 mercury 8hp die when i shift the gear and start tu throtling.. can you help?

[@irishwake1000]

Thanks Sterling, very informative video. I threw a .060 jet in place of the standard .046 in my 8hp to try and get a little more OOOOMPH out of the motor. Just couldn't quite get up on plane with my wife and I. Not surprisingly it's running a little rough and I can't seem to get it smoothed out. Any suggestions or am I wasting my time and just need to put the .046 back in the carb. Thanks again for your videos.

[@82HEADCASE]

Yes thank you so much for your videos 👍

[@aimeeclift3989]

great video, thanks for the info

[@user-so5ek4xt1o]

My motor is a 1989 mariner 45 hp 2 stroke on a 18 foot pontoon. It is using 6 gallons of gas in 1.5 hours on the water and the top speed is 7 mph. The carbs have been rebuilt. Any suggestions???? We have adjusted the carbs, but there is no change. Motor runs great, it is just guzzling gas and going half the speed it should.

[@matthewpirraglia9444]

Took off carb, cleaned and replaced gaskets. New plugs. Starts right up, jumpy when I'm on the throttle. Thoughts?

[@lazydragonslayer]

I wish I could find your timing video

[@tytml62]

Fantastic video, thank you

[@AlgomaOutdoors]

So I’m having an issue with the exact same motor. It runs well until about 3/4 throttle and then bogs down.. checked all hoses, tank, primer ball, still having issues

[@diamondstateautodiagnostic5250]

What would cause a Mercury 25 horse to start and run good even when it's cold but if you stop and fish for an hour and go to restart it it will start on about a half a pull and Run 5 seconds and then die and it's really hard to start in a spark plugs and dryer

[@user-ou1pz3tn3m]

great video you helped me out!

[@gregscarlett7747]

Great videos. I've been watching them all. I have a question. I have a 25 hp 2 stroke. Motor starts but won't idle. I've recently notice that there is a small port on the right side of the carb that squirts gas out a little. No idea why. Gas stain in the water. I can get it to run by giving it throdle. Any ideas what could be causing this?

[@benjaminl4700]

It's your float. She stuck

[@joshd2689]

I just picked up a ‘93 9.9 last week and have a carb kit, impeller, seal kit, etc on the way so the videos will definitely come in handy. Anyone know where one might find a pdf of the service manual online for these?

[@martinmarine529]

I sell a digital copy of it for $20. Just message my Facebook page and I will hook you up. Just search Martin Marine on Facebook and look for my logo with the guy in the Jon boat.

[@deanh7190]

@@martinmarine529 Is there another way to obtain this without subscribing to Fascist Book? TY

[@Andrew-vc4pj]

Need help. The motor will.idle fine and when I put it into forward gear at 75-100% full throttle. When I decrease the throttle speed to say 25-50% the motor stutter and quits. Does the carberator need to be cleaned? Is there a replacement carberator link?

[@yndalecioluna6081]

Hello i was watching your vid on the kam adjustment I have the 1998 merc 6 hp mine dont have the little adjuster dont know if its missing the kam is on there but the screw on top dont have one is there another way to adjust it let me know thanks

[@pauldavis4287]

How do you adjust the carburetor (especially at high speed) without a special propeller and a tub to run it in?

[@joenobles1086]

Great DIY the only problem I'm having is trying to find a choke assembly for my 1985 mercury 25hp xd outboard got any suggestions? And thanks for the sharing

[@Xmenfan68]

I start my 73 20hp mercury motor n the shifter speed is all way down but idle speed is to fast do i adjust throttle cable or something else

[@cwinder11]

Thank you for the great videos. In adjusting my carburetor on 9.9 I seem to now have a mist of fuel coming from somewhere and it’s backfiring?? Too rich? I had just replaced carb kit last year.

[@martinmarine529]

If it’s backfiring you have it to lean turn it just a little bit counterclockwise. A lot of times if you have had it running in a bucket or something for a good bit while adjusting as it gets loaded up with a lot of unburnt fuel.

[@mrreddog]

Got a 99 Merc 15hp 2stroke, starts right up 1st or 2nd pull every time & runs good at speed. But idling or trolling I get a misfire often and heavy gas smell & more smoke than should be?? She does 20mph loaded up with 3 people in a 14ft smokercraft voyager & 9x9 prop. Sounds great & good power up on plane, but heavy gas smell & misfire at low speed, any idea where to start?? Thanks.

[@jameswatson5783]

Hey, followed your carb settings and now it will idle all day no issues but I have an issue under load, it will run no issues for the 1st couple of mins at open throttle but it will become realy boggy after that, then turn it off and start again no issues for a couple of mins and then runs like crap again... When I got the boat the gas had gone super stale and bad so pulled the carb off cleaned everything and put back together. Now it runs like this, obviously the boat didn't run when I got it

[@mitchellsmith7739]

Did you work out what the problem was?

[@devinedwards7332]

Thank you Guys so much

[@yndalecioluna6081]

Hello Sterling i just picked up a 9.9 merc 1998 the issue is the tail tell pee port water comes out hot i installed a new water pump and threm and still hot then i took the therm out and the motor was not hot any more the tail tell water was warm what do you think is going on with this motor head gasket dirty water ports or the pick up water tube under the motor i need your advise thank you

[@johnnycruze7846]

Any videos on changing lowet unit bushings? Or swivel bushings? Unsure of what its called. Please ")

[@glenngraham302]

Hi I have an 87 Merc 9.9 that needs a timing adjust. We rebuilt carb and turned timing screw. Is there a starting point? it is all the way in now and that cant be correct. is there a way to DM you? THANKS Glenn

[@unclesam7660]

Best video

[@joej.4170]

2 questions: The idle link bar, where does it connect inside the flywheel area? 2nd: My idle doesn't have a brass screw on it like yours so it can be adjusted, its the exact same motor tho. How do it bump up the idle speed if there no screw?

[@skunk929]

Hey Martin Marine, Thanks for the all the help rebuilding my 6hp! your videos have been extremely helpful. The motor im working on was missing the max timing screw. I've got a replacement but havent installed it yet. Should I put it in or can I run it as it is until you post the timing adjustment video?

[@martinmarine529]

It will be OK to run it without it

[@doomsdaydad2488]

Were does the thermostat go? In the back on the cylinder head? I was checking on a water pump problem and removed a cover on the top cylinder, the tell tail hose was hooked to that cover. There was nothing under the cover but the water jacket was visible. Thermostat goes there? Thanks

[@martinmarine529]

It sounds like your thermostat is missing. Yes just pull that cover off with the hose coming off of it and if nothings in there it’s missing.

[@alexanders6248]

A video on that would be nice.

[@yexiong4793]

Hey I having issues with a mercury 15hp 2 stroke. Seem to have a oily leak coming from the carburetor, dipping all the way down to the propeller. If I'm running too Rich will it cause the gas/oil to leak from the air intake? Because I can see some fuel and oil residue there. Thanks

[@davidturben7686]

I got 15 hp 2 stroke I use it trolling for walleye a lot and for some reason when I kick it out of neutral I try to get that real slow troll but for some reason it dies last year it ran just fine when I would barely put it out of the neutral and I would get that slow trolling for the fish and it right now it don't seem to be gone and that slow as speed I have to kick it up a little bit or dies what should I try to get that slow idle slow troll back to where it was thank you in advance for your great videos

[@ianbezubiak2356]

super handy videos.

[@ryonmailnurse]

What does the bolt on the fuel pump that you say breaks off actually do thanks

[@martinmarine529]

It stops the timing from advancing anymore at wide open.

[@zachtaylor6465]

I have a 9.9 that I have rebuilt using your vid’s and it’s running pretty good. My question is I don’t have an idle speed screw. The manual says to loosen the locking screw, press the cam down then tighten which I have done. But it still seems as if I need a little more throttle to start. As soon as I lift that up a bit she fires right up and runs good. Any way to get this adjustment? Thanks

[@johnkimball5143]

I have 1999 Mercury 9.9 what fuel and oil mixture should I run

[@ffhill85]

I just did the carb rebuild after watching you video. (Great video) i put it back together and where its labeled "top" its leaking fuel when priming it. What would be the cause of that?

[@martinmarine529]

I would try pulling the bowl back off. Then pull the float out. The float is probably stuck. Then lift the leaf springs underneath the float and drop that pin back out. Then just reinstall it all again and should fix it. Make sure the curved sides of the float are faced towards the bowl.

[@ffhill85]

Thank you sir Ill check that out. Keep them videos coming!

[@joshmilat1048]

Great videos that helped me get our outboard running again. We live on our sailboat and use our dinghy as our car so it is incredibly important to have a strong running motor. I had the same issue with the leakage from the top area. The bowl appears (sounds) to be free when I shake or roll the carb when it is off the motor. Any other thoughts? Could you post/send a quick picture of the gasket orientation under that plate labeled top?

[@joshmilat1048]

@@ffhill85 did you find a fix for the leak? I am having the same priming leak issue. Among others.

[@martinmarine529]

@@joshmilat1048 The needle under the float is not seating. Remember when you pull the float off and lift the brass hinge there is a small needle that falls out. Either the needle is missing or it is not seating properly.

[@henklantinga8968]

hi, i have a WMC 83 carberator do you know if its for a 9,9 hp or 15 hp mercury thanks

[@dywildatheart]

Sterling great video, new subscriber. Where is thermostat located?

[@sprayo1e]

What would be a good idle rpm? I have a tach I want to use as a starting point

[@NiceBike2418]

Do you have a video on the timing adjustment?

[@Ken-tc5mp]

2quick questions: 1. how far is the rsnge to turn to adjust past the 1 1/2 turn start. 2. Thermostat? Never heard of one, where it is / goes, how to get one. Thank you. Very much. Ken

[@martinmarine529]

The thermostat is located on the back of the motor follow the hose where the water exits the motor and remove those 2 10mm bolts. The first question I’m not sure exactly what you’re asking.

[@Ken-tc5mp]

After turning screw to 1 1/2 turns out from seated; how far in each direction can I go, or just listen to how ot sounds?

[@martinmarine529]

@@Ken-tc5mp It just depends I wouldn’t say any more than two turns richer I am probably no more than one turn leaner. But it just kind of depends.

[@pikeandtrout]

Thank you for the great/informative video. If you don't mind a question. In your opinion is it okay to replace the twist on fuel filter assembly with a more standard inline filter? They inlines by quicksilver (re ex.) are much more available.

[@martinmarine529]

Totally fine

[@zzzrichieboy1]

Hey, when adjusting the cam screw should the motor be in neutral?

[@jackrabbit5047]

That was good, thanks. What is the function of the little switch on the lower side just left of the choke knob? Mine has the same thing, and it seems to flip like a toggle switch.

[@martinmarine529]

That is the kill switch. Make sure it is in the position to crank the motor. You can buy a lanyard that hooks in there that you can clip onto your side.

[@alexis1988]

Hello my friend.i have a 3 meter novurania canguro inflatable.will it run good with a Mercury 9.9hp?

[@hunterslifestyle625]

Thanks

[@Andrew-vc4pj]

What do you mean by touches?? On the fuel mixture

[@TheWanderer4171]

Question, I have a 8hp Merc that is idling fine in a garbage can, revs up fine in the garbage can… once I put it in the water under load it falls on its face & dies. Any suggestions? I’ve cleaned the carb twice and changed the plugs.

[@mitchellsmith7739]

How far out is the low speed mixture screw?

[@brianschafer2723]

Had to replace trigger stator and cdi box. Now engine runs like crap. Should I do a carb adjustment or is it bad gas

[@ct1762]

i seriously doubt all those parts were bad. did you do proper DVA testing or just blindly replace parts? did you check timing after?

[@aboyFinn]

I have a question for your Sterling. I've rebuilt my carb following one of your videos and it went fine although I still have to do a little adjusting. It starts right up but really bogs down when I try to accelerate. Maybe the rich/lean adjustment? My question is really about my fuel line. I want to replace the gray fuel line with a better product. I'm concerned that the liner in my hose may be breaking down and causing restrictions. I will likely get some fuel hose from West Marine or is there a suitable alternative available from an automotive store?

[@mitchellsmith7739]

Did you sort it out and find why it bogs when accelerating?

[@aboyFinn]

@@mitchellsmith7739 I had a few things going on but the bogging (I think) was caused by water in my fuel tank. I did a number of things but eventually found this to be the likely cause of the bogging. A friend tipped the tank up onto a corner and sucked fluid out with a hose. I had over a quart of water in the tank, probably from ethanol added gas separating. Later I found the small ball bearing in the primer check valve to have gotten 'stuck' in the spring but that caused a larger problem.

[@Andrew-vc4pj]

When I put the motor into gear forward or reverse it dies about 10 seconds in...but it'll idle just fine. Thoughts?

[@boatrvme8478]

Carburetor

[@christophershoe9642]

Mine is the opposite, starts, won't run after 10 secs

[@Andrew-vc4pj]

@@boatrvme8478 I ended up taking the carb off and cleaning it up and replacing the spark plugs. Runs great now

[@t444edt3]

How often do these carbs need to be rebuilt? I did the master kit w fuel pump last year. Thanks

[@martinmarine529]

About every 3 years or so just depends really. If it’s running good leave it alone.

[@jacoborthamen79]

tip of the throttle ? what is the lock for? I don't have a Manuel .

[@ct1762]

throttle friction adjustment

[@mariomarcial2238]

I have a 15 hp two-stroke mercury that only runs like 12 mph. will this help to run faster?

[@martinmarine529]

What size boat is it pushing and what prop are you using?

[@Rxpx300]

Hey! Do you know why the motor puffs a lot of Smoke ? Merc 2stroke 10hp 2006.

[@martinmarine529]

You may have the fuel mixture screw too rich.

[@Rxpx300]

I have wrote to you at Facebook

[@dylanhooper5114]

What year model is this motor?

[@djadrianoestevam2516]

hello friend do you know where to find the mercury carburettor 1983 18hp?

[@martinmarine529]

Maybe check eBay

[@johnnycruze7846]

Could you do a carb rebuild video please?

[@martinmarine529]

Already have one just check out my other videos

[@user-wm1xj7jr4m]

Do you sell the parts and kits, on line?

[@riverrivers250]

I got like a mercury 2stroke 25hp 1999 ???,,,,, the motor does not idle at all. I have to open the throttle all the way almost just to start it.. and keep moving forward jus to keep it running.

[@riverrivers250]

I dont know nothing about outboards too. Lol just drive it HAHA

[@riverrivers250]

I see that primer knob on this video,,,, But mine has no words on it.. all faded. U think it could just be that???

[@martinmarine529]

Sounds like you have a carburetor issue. I would take it to a local outboard shop and get them to rebuild it. The choke you just want to turn all the way clockwise and pull it out when trying to start the motor and push it in when the motor cranks

[@mike_oe]

1:03 "make sure you press on ...this.." I came to learn what function "this" has. Why not call the parts by their correct names rather than "this" and "that". I'm disappointed.

[@florianborkenhagen9434]

Thx for your Videos, i have a Mariner/Mercury6, because of low compression i have to change the Powerhead and the Ignition. Can u make a video how to set the timing correct? Or do you know where i can download teh manual?

[@Andrew-vc4pj]

I rebuild the carb...and now I can't get it to turn over.

[@toddamlee3854]

Rebuilt carb, but still need starter fluid to start... Any suggestions?

[@martinmarine529]

It’s possible you have a problem with your gas tank or hose.

[@ct1762]

why are you using starting fluid on a 2 stroke?

[@loganfrench8597]

Can you converted a 9.9 to a 15 by changing the carb?

[@martinmarine529]

You will gain a little bit of horsepower but no it still will not be a true 15.

[@andy6043]

Can you change a 6 hp to 8 hp by changing the carb ? (2-stroke)

[@martinmarine529]

You can do that but it still won’t be a true 8 hp. It will give you slightly more power though.

[@andy6043]

@@martinmarine529 Thanks ! Do you happen to know the approximate cost ?

[@martinmarine529]

@@andy6043 Are you looking for the cost of a 8hp Carburetor? If so it can vary you may be able to find a used one for under $100 on eBay or a new one will probably be near $300.

[@andy6043]

@@martinmarine529 Sounds like it wouldn't be worth the cost ?

[@martinmarine529]

@@andy6043 Better off selling it and getting a larger motor

[@davidju6666]

6:05 so funny