In the hope of helping others out here are some common things i know of, if anyone else is aware of other tips for specific outboards to avoid problems then please add them in....mods may even sticky it if we are super good!!!
Please note this is not intended as a brand bashing excersize as all engines will have issues if you look hard enough, but these ones potentially are easily avoidable by users that i've seen.
This obviously won't replace doing your own homework or a good dealer but it is clear not everyone has as much time to browse the web as me while at "work"
Every outboard these days will come with good instructions and if you have a warranty you better follow it to the letter, you can find the operating manuals for just about every engine on the makers website so worth looking at and versing yourself with those.
Some general guidelines which have served me well
Avoid supermarket fuels (yes i have had to replace every filter on my boat after 1 trip to a supermarket, perhaps i was unlucky but not taking another chance..YMMV)
Top your tank up when not in use or moisture can build up. Modern injected outboards will take no prisoners if you feed them water with injector and pump problems round the corner. Some fuel stabiliser from halfords will do no harm either if leaving it for a while.
Use good filters and replace them as per guidelines in your manual. (remember the fuel tank filter if you have one)
Make sure your battery is in good condition every season, keep them out the cold and in winter a trickle charge will do no harm if you can get them in the house. Failing that i try to start my engine every 2 weeks in winter for atleast 15 mins to keep things topped up. A DECENT solar panel will also do the job of helping if no other power drains and you are in decent light. Remember to secure and grease the connectors when refitting!
I do not winterise outboards anymore as i use them all year, if you are then your manual will have info on performing that. I've "lost" an engine in winter when i was winterising them with a cracked block. since then i've just looked at weather and ran my engine when i know temps are above 0 for a couple of days in a row. If there are prolonged periods of below zero then i run it up and put an outboard cover on it for a few days to keep temp up while block drains. i usually put outboard up and down a few times to make sure as much water as possible is out of it. i like to leave the engine in the down position to drain.
Your manual will have info on greasing/maintaining things, it is important to do that.
An overlooked part of the engine is the cables/steering/trim rams/prop, make sure these are cleaned and greased correctly.
For the outboard mount/saddle i like to use a corrison spray, i love this stuff as it leaves a coating on. one spray is good for a couple of months in my case-
Corrosion Technologies makers of world famous CorrosionX and RejeX
Suzuki df (25-300hp)
Every season the leg should be dropped and good quality grease applied to the drive shaft where it enters the powerhead, it is reasonably common these stick without doing this periodically and removing it involves taking a saw to the mid section or worse...£££££££. I've seen the odd mercury and yamaha with same thing but not as often, do no harm on any engine anyway to perform this.
175-300df
Butterfly flap screws in throttle body come off and the engine ingests them, usually you only notice this when you get the dreaded tapping noise of a piston smashing the screws into the head. it is easy to fix with some glue/loctite on the screws. I don't think the 200's have dual intake runners but i'll confirm when i check mine soon.
https://www.thehulltruth.com/boating...u-got-one.html
140df
Suzuki used a poor choice of material for the plug which results in needing a new powerhead WHEN corrosion gets the plug, there is an cheap part to fix it if you have one of these. Not sure of years impacted but worth a check (keep in mind you may break the engine trying to remove the old one if it has been in there a while, your choice)
https://www.thehulltruth.com/boating...osion-fix.html
https://www.amazon.com/Suzuki-Outboa.../dp/B008322370
Any suzuki with IAC valve
Seems common these fail with lots of idle work, usually will get an 3-1 error code or the outboard will not start or idle roughly or a combo of these. The suzuki part is very expensive but you can buy a mitsibushi part that will do the job for about 1/10th of the price. Some say they only get a few hundred hours out of them and they fail but i've seen people with 200 hours on genuine ones that fail. i believe it is related to a lot of idle time so if you don't idle too long then it maybe worth looking into iac options. some info here to get started-
https://www.thehulltruth.com/boating...r-strokes.html
Yamaha F150-250 (2004-2008 seem to be worst) mid section corrosion-
There are a lot of these outboards about which is perhaps why you see so many of these, i think you would need to be unlucky to get this as i've seen many others not have the problem. if you can it is imperative you flush the motor as often as possible (that applies to every motor really). I have read flushing will stop it and it is a fault with a coating or lack of on the part but flushing won't cause any harm and a decent chance would prevent it or atleast prolong.
MAR-EXHKT-04-00 EXH KIT F200-250 04
http://www.rib.net/forum/f36/yamaha-...els-60698.html
Yamaha 350 v8
Best google this if you own one of these, basically they need flywheel replacements every 80 hours when ran between 3500 and 4500rpm i think it was, currently yamaha are picking up the tab for this. best checking if they will honor doing it on a used engine (in writing!) if your lucky enough to buy a boat big enough for one (or more!) of these monsters to come on. Lots of these in USA and owners love the grunt and are happy to put up with the flywheel replacements now and then....with price of gas out there i'd be delighted to do the same
evinrude 60hp etec
few reports on this forum of saddles breaking, worth having a search on this forum. best advice is to make sure the saddle is supported. i.e on the transom or fit a spacer of some kind if engine raised up. Someone on forum had no joy with warranty replacement last time i seen thread so worth looking at as a transom support may save a lot of money.
etec EMM's
if i see any major etec issues it is normally relating to this. they are quite expensive i gather but some companies in USA have started doing a repair service. There are some things you can do though to help such as flush the motor often and let it get to operating temp to open the stats. you should also make sure you don't try using a dodgy battery as they don't seem to like it (no modern engines do to be fair). Best bet is checking it out on-
https://www.etecownersgroup.com/
Etec plugs
every etec owner probably knows this but this says all you need to know-
Spark Plug Indexing – How To | Evinrude Nation Community
that is all the ones i can remember, hopefully others can chime in with some tips for their own or if the above is complete BS as i'm happy to be corrected and edit the above if mods will allow