Mercury 20 HP 4 Stroke Maintenance Tips

Basic maintenance that you can do yourself. I hope it is helpful.

[@stefandoering7855]

Excellent instructions, Thanks so much for your effort RM putting this video and words together- awesome job. It helps me a lot with my first encounter of my 20hp 2013 Merc.Thank you

[@RM-ey5ym]

Thanks for your kind feedback Stefan...greatly appreciated!

[@thetoledos8335]

Excellent video and very well explained five stars

[@rossmay188]

Thank-you for the feedback... greatly appreciated!

[@ironix1]

Informative. Thank you

[@RM-ey5ym]

Glad you like it...thanks for the feedback!

[@darrellsmith5395]

Yes very helpful thank you.

[@kacieclanton7796]

Great video, thanks

[@RM-ey5ym]

Glad you liked it. Thanks for the feedback...greatly appreciated!

[@GurpreetSingh-op3ie]

Thanks for very informative video. Is there any fuel filter that needs replacing?

[@RM-ey5ym]

Hello Gurpreet. Yes, there is a fuel filter that should be inspected each year or if your engine is running rough. For the location, it depends on whether you have an EFI or a non-EFI engine like the one shown in this video. If you have exactly the same engine as this one, the fuel filter is located on the lower, left rear of the engine compartment. You can just see it at 10:45 minutes into the video It is a white plastic filter. If you have the EFI version, then you should check out this KZbin video that explains how to replace the fuel filter on that model...kzbin.info/www/bejne/baCwlZSdm9plhdE&ab_channel=BakkenMotorAS They are very easy to replace. I hope this helps...good luck with your maintenance and thanks for your feedback!

[@GurpreetSingh-op3ie]

@@RM-ey5ym thank you.

[@WeeWoo93]

sorry if this is a very dumb question, but the oil up top near the crank is the oil the injector uses and mixes with the gas right? and then the lower unit oil is a completely sperate oil?

[@rossmay188]

No such thing as a dumb question...no worries. If your engine is a 4 stroke, the oil you need to put into the top fill hole needs to be 4 stroke engine oil, preferably by Mercury. That is a completely different oil than an oil injector oil and different from the lower unit oil. An injector oil mixes with gas. The 4 stroke oil doesn't mix with gas...it stays in the crankcase. You need to know if your motor is a 2 stroke oil injected motor or a 4 stroke engine. The lower unit oil is completely different from the engine oil. If you check your manual, it will tell you the kind of lower unit oil you need to put into the lower unit. It will also tell you the kind of engine oil your motor requires. I hope this helps. Cheers!

[@mud074]

Thank you so much for the video! I am trying to learn the basics of maintenance as I am about to buy my first outboard to put on my dad's old boat and want to save money on trips to the mechanic. This was very helpful. What kind of schedule would you recommend for these? I think I should do the impeller yearly and the oil at least once per season, but what about the anodes and thermostat? If I get these maintenance items done regularly, are regular visits to the dealer as the manual recommends really something that is needed or could I get away with only doing it every couple years or so?

[@RM-ey5ym]

Thanks for your comments. I would suggest changing the engine oil and lower unit gear oil after each season before you store the motor for the winter. If you are using your motor in fresh water, the anodes won't need to be changed as often as they would in salt water...same for the thermostat. For both the impeller and the thermostat, as long as there is water strongly squirting out from the tell tale opening at the back of the engine, both should be working fine. If there is a weak or no stream or if the water is coming out hot from the tell tale, the impeller or the thermostat may need to be replaced...likely the impeller for weak stream. You can check the impeller annually when you drain the gear oil from the lower unit if you want to be extra sure. No need to check the thermostat unless you suspect the engine is overheating. When you replace the engine anode, you may want to replace the thermostat at the same time if the thermostat looks grungy. If the other more visible anodes on the motor are in need of replacement, chances are the engine anode will need to be replaced as well. For fresh water, you can go several years before needing to change them...not so much for salt water. I highly recommend flushing your engine with fresh water after using the motor in salt water. Salt-A-Way is a great product to clean out salty water from the motor and will extend the time needed between engine anode replacement. If you change the engine oil, lower unit oil, impeller and anodes yourself, there would be no need to take it to a mechanic unless you are having other issues with the motor. The nice thing about these small outboards is the simplicity of servicing them yourself. Hope this helps!

[@mud074]

Thank you so much! That's exactly what I needed. I've been trying to figure this stuff out but so much of what is online comes down to "do everything the manual says" or "go to the dealer every year". And the thing is, the manual says go to the dealer every 3 months! Now I'm double as excited to get back out on the water again after so long. Just gotta find a motor that's actually in-stock.

[@RM-ey5ym]

@@mud074 Glad to be of help...cheers!

[@fomocosolow]

I have this same model and have noticed an oil leak from inside the cap/cover. It appears to be coming from the right side of the motor looking from the back of the boat. Was almost empty the other day when I checked- nothing on the dip stick. I am a new boater. Any help is appreciated thank you

[@RM-ey5ym]

So the oil is leaking from the oil fill cover? Do you know what the oil level was when you first bought the motor?

[@fomocosolow]

@RM-ey5ym I apologize. The main cover or lid that covers the entire motor. I guess I meant it wasn't leaking down by the foot or prop . Several inches to the right of the dipstick towards the front of the motor. It's almost directly across from the oil filter. It's inlaws boat I have been using but had only been in the water a few times I believe before I got it

[@RM-ey5ym]

@@fomocosolow Hmmm...Have you started the motor before you noticed the leak? If so, did it run okay? Check that all bolts are secure on that side of the engine. If you haven't started it yet, fill up the oil and try running it in water and see if you can spot exactly where the oil is leaking from and how fast the oil is leaking. If it is running rough, shut if off and take the motor in for service. Are you located where the winters are very cold or are you in a warmer climate?

[@tonywyant8957]

My 20hp Merc always starts fine at the dock, but after running my boat for about 1/2 hour to my fishing spot and shutting it off I find it very difficult to start it back up. I may only have been stopped for only 20 or 30 minutes but the motor does not want to start. Ant tips or ideas on what I need to do to fix this problem.

[@RM-ey5ym]

Hello Tony. A common cause for the issue you are having is the stator. Not saying that is necessarily your issue but it could very well be. If you end up having to replace the stator, Mercury Marine recommends that the switchbox be replaced as well. A bad stator can weaken or ruin a good switchbox. The old switchbox can fail shortly after a new stator has been installed. Unless you have a flywheel puller and can test the stator yourself before replacing it, it would be best to have a marine mechanic do this for you. If you want to take this on yourself, here is a decent video on how to test and replace your stator. kzbin.info/www/bejne/fqKuZYWnq5iLgpY&ab_channel=WildnWonderfulOutdoors Cheers!

[@tonywyant8957]

Does removing the "fuel demand valve" cause any problems or harm.

[@rossmay188]

Yes. Removing the Fuel Demand Valve can cause flooding of the engine and could result in engine failure. Removal can also cause excess gas to pollute the water. A new FDV isn't expensive to replace. Hope this helps. Cheers.

[@jelleroozeboom6024]

Hello mate, I have the same engine but it has trouble starting... especially when cold, every time it starts it also gives a 6 ish second beep and the warning light is on for 6 seconds. the oil level is fine and it has a new filter.... do you have any idea what it could be, I was thinking maybe the thermostat?

[@rossmay188]

Hello! No worries about the beeping and warning light. This is a normal startup process for the engine. If it keeps beeping and the warning light stays on, then you have an oil issue. Cheers!

[@jelleroozeboom6024]

@@rossmay188 but it stays beeping for longer then usual. My other friends mercury beeps for like 1 sec

[@jelleroozeboom6024]

@@rossmay188 And it starts bad

[@fishingmaster99]

How did you move the motor up? What button? I have a 2011

[@RM-ey5ym]

The motor in the video has a hydraulic power tilt. If your motor has that feature, the button is on the side of the motor near the cowling. Hope this helps.

[@ricardo____]

Hola, yo tengo un motor igual, podrías hacer un vídeo de cómo instalar comandos a distancia?

[@RM-ey5ym]

No puedo crear un video de la instalación del control remoto porque ya no soy dueño de este barco / motor ... lo siento.

[@ricardo____]

@@RM-ey5ym a bueno, gracias igual por responder

[@tonywyant8957]

is there a fuel filter or water/fuel Seperator on this motor??

[@RM-ey5ym]

Hello Tony...yes, there is a fuel filter on this motor. The manual will tell you how to replace it. Cheers!

[@tonywyant8957]

Thanks

[@bigblockcutlass123]

How do you like your fin?

[@RM-ey5ym]

The fin works very well for getting the boat up on plane quickly.