Mercury 9.9 mixture

[lockieboi]

Hi all, i have a mercury 9.9 2 stroke think its a 1995, no model no but i do have serial no.

Engine runs fine but every now and then it wont start as a result of it being flooded, i think.
When this happens i remove plugs, clean them up refit and it fires up first time.

I am running it 50:1 which is what the seller told me to use it on but i am now wondering if it should be 100:1 and if this would solve the flooding issue?

Any help on how to find out the mixture or what could be causing this?

Thanks

[doggypaddle]

I think 100-1 engines are as I understand it largely the same mechanically as 50-1 engines, but specified 100-1 to reduce emisssions. (I had a 100-1 yamaha and was told to run it on 50-1 for heavy wide throttle use and only 100-1 for pottering about).
50-1 on a 100-1 engine is unlikely to foul the plugs, and will probably reduce engine wear.
I would double check you have the right spark plugs, and use only a good low ash marine grade 2stroke oil.(quicksilver)
(may be teaching granny to suck eggs but some people do use car engine oil or bike aircooled 2ST oil)
I would also check the choke is fully returning to fully open.
other than that give it more beans
only other thing I can think of is we had a fleet of hire boats with 9.9s on and people used to flood them. we always used to thell them one pull with the choke out, then shove it in. more often than not they would give 3 or 4 pulls on full choke and flood the engine. it would then take 10-20 pulls with the choke in and throttle as open as possible in neutral to clear.
perhaps all merc 9.9s are really prone to flooding if slightly over enthusiastic on the choke?
Also try stopping the engine by disconnecting the fuel line, so when you pick it up to transport it you dont empty a carb full of fuel into the crank case

[lockieboi]

Thanks for your reply.

I am using TCW-3 oil which i think is quicksilver.

Would this be Low ash?

[actions]

Originally Posted by lockieboi

Thanks for your reply.

I am using TCW-3 oil which i think is quicksilver.

Would this be Low ash?

I use to have a 8hp Merc and a friend the 9.9. Both ran on 50:1 mix. Quicksilver TCW3 is perfect stuff, good quality.

[doggypaddle]

Originally Posted by lockieboi

Thanks for your reply.

I am using TCW-3 oil which i think is quicksilver.

Would this be Low ash?

thats the stuff i use that in the yam80aet at 500ml to 22.5l (coke bottle full to one Barrus tank) and never get any issues at all even idling for an hour or so. that works out at 45-1
do you run the engine out of fuel to stop it at the end of the day?

[lockieboi]

Yer I always run all the fuel out of it at the end of the day.
Just checked on the net and the plugs I'm using are for mercury 2 strokes.
Bit of a mystery then it would seem.

[doggypaddle]

always keep a plug spanner handy