Ms391 and water

[Aaron]

Well not been best of weeks but to top it of my 391 was dropped in a ditch, it was picked up ace hap and turned straight off. Stripped it down and there didn't seem to be any water in the intake and a dry filter. I did see you exhaust spluttering though. Cleaned it all up as seemed fine and started perfect, only to run for a few mins then stall, it won't start and there's a horrible rattle when you pull it over and I'm praying its not what I think it is!! Any help fellas?? Ta in advance.

 

Aaron

 

 

 

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[Stubby]

Mmmm. Bad luck mate . Did it go right under so as to suck water into the cylinder ? Maybe it should have been left running , revved up even to dispel water quick and keep some oil in there. What can happen , depending on your filter , is the filter gets wet and disintegrates / collapses making it seem like its on choke all he time but you have stripped it and looked so not that I would think . Spud will know what to do .....

[swinny]

Should have taken plug out and pulled over quick. Sounds like its hydro locked. Engone cant compress water.

 

Knackered piston or snapped crank. Conrod

[Rich2484]

I doubt water lock as it was running when taken out of ditch. Water lock would have stalled it there and then. And the big end would have snapped instantly. Not fired up after. But then I may be wrong.

 

Take the pull start and clutch cover off and see if there is anything a miss with those. Ensure all is tight and not broken, could just be a fin or pull start part rattling around the flywheel area when pulled over.

 

Easiest way is to take the exhaust off and look down the port while gently turning over. Will see the piston moving about inside.

[Stubby]

If it was hydraulic lock it would not be still running when you fished it out .

[swinny]

Ahhh didnt see the still running part... needs a good check over still. Good luck

[Aaron]

You lot are full of the joys of spring! ha. cheers for the input so far.

 

Aaron

[WorcsWuss]

Have you flushed the tank, fuel hose and replaced the fuel filter?

In the same way the engine draws air in through the tank breather to replace the fuel it uses, it could have drawn water in when submerged and contaminated the fuel....

Can't comment on the rattling....

[spudulike]

The fact it ran afterwards is good and sort of means that all is OK - it has probably run the fuel out of the carb, drawn in the water impregnated water in the tank and has now got water in the carb.

 

Don't leave it like this, either get it running or put it somewhere nice and warm to drive off the water.

 

Drain the oil and fuel tank, take the plug out, turn ot upside down and spin it over on the starter handle quickly to get the water out of the crankcase.

 

Turn it the right way round and get some WD40 down the plug hole and turn it over, do it again with it lying on the clutch side and again with it lying on the recoil side - make sure the WD40 gets in to the main crank bearings - don't want them rusting.

 

If it won't start with fresh fuel - even after warming the spark plug on the gas stove - the carb will need a strip, a clean out, dry and reassemble and try again - make sure the airfilter is dry.

 

This should get it going - hopefully the rattling is nothing - if the saw ran afterwards, I don't think there is an issue with the piston compressing against water and bending the rod!

[Aaron]

Cheers SPUD!! i will report back with any news, cheers for the help