spluttering 2 stroke!!

hoggibear

hello everyone,

iv got a quick question, im currently using an old Evinrude 30HP 2stroke outboard engine, this engine is more then 10 years old but has been looked after very well by the previous owner.up until a week ago it was running fine, now when the engine is in neutral or running at low revs its 'coughing' and 'belching',
i was told this could be water in one of the carbs but i thought some one here might no a bit more.
when she gets going its running fine, only problems arise at low revs, shes also become slow to start once the engine has cooled back down.. any help or advice is much appreciated

Pigeon Reaper

sounds like the carbs alright. Try draining them to see if water or something else comes out. It could also be one of the carb jets blocked by dirt. Make sure that the oil is also mixing correctly as too much oil could cause bad behaviour at lower revs.

sham08

What is the correct oil/ petrol mixture for a 2 stroke engine? I have heard so many different mixtures I'm a bit confussed as to the correct one. My engine also splutters a bit and cuts out at low revs but behaves perfectly at higher revs and it is a very new engine. Thanks

hoggibear

cheers pigeon

is there much involved in draining the carbs? i no there is a small valve/plug on the side of the engine with a rubber cap on it, near the fuel intake, do you open this valve to drain them? thanks..

Delphi91

sham08 wrote: »

What is the correct oil/ petrol mixture for a 2 stroke engine? I have heard so many different mixtures I'm a bit confussed as to the correct one...

I have a 3.3HP Mariner (just bought it new) and the mixture is 100:1 i.e. 10ml of oil to 1 litre of petrol.

Pigeon Reaper

The mixture on most modern engines is 100:1 but it's best to check the handbook. To drain the carbs there should be a small screw under the float bowl which opens a small drain. Make sure you have something to catch the petrol under the carb before you open it. The rubber cap is probably the vacum tube used for balancing and testing the valve.

scaldybelt

I have a 70hp 2 stroke - 50:1, a 2hp 2stroke - 100:1.
Recently had a 60hp and 4hp - both 50:1.

I suggest searching tinternet for the exact engine/age and see what the quoted ratio is. I wasn't sure for the 4hp, and found out that way.

Steve.N

Hi,

Had the same problem with my 55hp 2stoke. As you say it's propably water in the fuel. This is quite normal on boats (due to condensation in the fuel tank), the water usually sits in the bottom of the tank with any sludge. You can buy a petrol/water separator filter from any chandlers (got one in Marine Parts in Swords for €60). Best thing to do is loosen the drain screws on the carbs, let them run through till any water is out and then clean your fuel filter. Clean your fuel tank as best you can and then fit a new sperator filter.
This should sort it out and prevent it happening again.

Hope this helps.