Mercury 40hp troubles????

[Bundy Bob]

Gidday all,

Just wondering whether anyone has any advice on whether to run your outboard fuel sysem dry after use by disconnecting fuel line. I have had differing opinions on this.

Also, has anyone had any trouble with 40hp Mercury (mine is 2yr old) 2 stroke tiller steer. Mine is fouling the bottom spark plug every 3-4 tanks of fuel and I am trying to ascertain if this is a common problem. A mate of mine has the same motor which does the same thing.

Regards

BB

[Jabba_]

This cant be true... Problems only ever arise on E-tec's.... Or so it would seem according to certain forums members...


It is best not to run the fuel system dry.. particulary if your motor is a DI....
Sorry I can't help with the second Question,

[stevej]

carby components are aluminium inc some fuel bowls


ally oxidises with contact with air offering the chance for crap to fowl the jets
so i say dont run it dry but then dont leave old fuel in the bowls for 6 months either

just start the thing once every week or two

[bluefin59]

I have had 6 outboards over the years all with carbies and i never run them dry its never been a problem for me just run it at least once a month ....matt

[DR]

a lesson learned...when i used my boat regularly i never ran it dry & never had an ounce of trouble... met a woman & did not use boat for a loooong time. while sitting fuel evaporated in the carbies, leaving a varnish deposit to clog the whole lot up. best way to fix properly was complete rebuild which was costly & uneccesary.

now when boat sits i still won't run it dry, it gets kicked regularly over in the flush bucket to keep carbies & inside of motor wet .
works for me

[bluefin59]

Some of the things women are responsible for ? Maybe get one like mine who wants to be out as often as me ,whoops did i think out loud again silly me::) ::) ::) ::) ...matt

[Clyde]

Had twin Johnson 30's on the back of the Clarke Abolone for 20 years and always ran them dry after cleaning them and storing the boat. Live in the bush so boat got used between 1 and 4 times a year. Always started easily with fresh fuel and have never had any problems.

Cheers,
Clyde

[Kleyny]

I have a 60 merc 05 mod.

I have found when i ran my dry the next time i tried to start it, it took a fare few cranks for it to fire. Now i leave the fuel in the carby and it starts after the first crank 90% of the time. this is useing it on average every month.

On the fouling problem i use only either merc or quicksilver oils and never had a drama. a mate has a 25 merc and he was using any oil he could get his hands on with the same result as you, fouling plugs. once he went back to quicksilver he doesnt have any fouling dramas.

neil

[Spaniard_King]

Bob,

Are you runing an accurate 50:1 ratio, Also do you have the correct plug? if you do talk to your mechanic about going up 1 heat range.. cause sounds like you troll alot eh?

[QuinnyDory]

Hey Bundy Bob,
Did a double take when I read your post.

I have a 2006 Merc 40hp 2str tiller (the tohatsu). Mostly good for 6 months - but did foul plugs during double oil period. I could rave on with frustration about how I was stranded 7 times on the water over the last 2 months, how Ive been back to the dealer serveral times to diagnose the issue. Bogging down out of the hole, plugs fouling (particularly the bottom plug) every 2 months at least. Staggering and hessitant acceleration, difficult starting when hot. To cut a long story short, the mechanic Im taking it to diagnosed the issue (full credit to him and I think he's a smart bloke) - they need a plug upgrade from a BR8 to a BR7. Since Ive had it out the last 2 runs its 100% - NO ISSUES. I have my new motor back :)

If you need more info Pm me and I'll try provide. Im no mechanic.

cheers.

[Bundy Bob]

Guys,

Thanks for the replies. I am meticulous with the 50:1 ratio. Always accurately measured. I have only ever used Quiksilver oil so oil quality shouldn't be a problem.

I do a little bit of trolling but mostly with electric motor because all my fishing is on freshwater dams.

QuinnyDory - I am most interested in your reply. Sounds exactly same as my trouble. I have noted your plug suggestion.

My most recent visit back to the dealer has resulted in me fitting non-resistor plugs. I only fitted yesterday and haven't had a chance to try yet. Fingers crossed.

BB