makita 4300 (help)

[harvey b davison]

Hi, started up my trusty 4300 this morning for the first time in about 2 months (it did have old fuel in), it took a while to start up which is unusual, but it then ran ok for about 5 mins. After that it started to 'pip/pop' type of thing with revs dropping and fighting to keep going. I also noticed the spark arrester inside the exhaust was glowing fire red. I turned the saw off and let it cool a little. After 5 mins the saw started and ran ok, but then within minutes it was running crap, and then i was getting the odd spark flying out of the exhaust. So any ideas please. Please be aware that i am not technically mind so you will have answer in basic terms please.I have also took a few photos of the saw.

 

Thanks

Harvey.

[harvey b davison]

Can i also add, that i put fresh fuel in and changed the fuel filter, but neither did anything to correct owt. Also when i got it back to my garage, i messed about with it a bit and altered the 's' and 'l' screws, so now i'm not sure of the correct settings for these.

[harvey b davison]

Anybody any idea, spud, shavey, gardenkit ??

[spudulike]

It sounds like the old fuel caused the saw to overheat and was in the edge of seizure. It does look like the piston is OK though so it may be OK.

 

Get some fresh fuel in it and run it up and see what gives. Is there any scoring on that piston? It looks clean in the pic!

 

The sparks will have been caused by excessive heta burning up the carbon in the saw.

[harvey b davison]

Cheers spud, luckily the piston seems fine, no scoring at all. I got the sparks after i had run it on fresh fuel for about 10 mins on and off. The problem now is i tried altering the L screw and S screw and not too sure where they should now be set at.

[billpierce]

try to find out what the factory settings are for the saw? usually 1 turn out on L and H and the idle you should be able to tell what a decent tick over speed is without chain creep.

 

my dcs 4301 has a spark arrestor also which glows red. i think this is normal and probably intentional as some sort of emission reduction (might be wrong? but mine has always done this and runs fine and has done for hours of work.)

 

check you plug colour after a bit.

 

good luck

[spudulike]

As Bill says, most saws have the H and L screws set to 1 turn out, not sure what your "S" screw is or if your saws carb has limiters on it.

 

You could fire it up, get the screwdriver in the H screw, undo it around 1 turn and then rev it flat out and turn the screw in until the saw sounds a little thumpy but revs to what is normal without screaming.....if that makes sense!

 

Set the L screw to 1 turn and adjust the idle to suit and see how it picks up/idles

[shavey]

harvey i would start at 1 1/4 turns out first then at least it wont be to lean

[shavey]

try to find out what the factory settings are for the saw? usually 1 turn out on L and H and the idle you should be able to tell what a decent tick over speed is without chain creep.

 

my dcs 4301 has a spark arrestor also which glows red. i think this is normal and probably intentional as some sort of emission reduction (might be wrong? but mine has always done this and runs fine and has done for hours of work.)

 

check you plug colour after a bit.

 

good luck

 

hello bill having trouble finding a 401 piston did you get one a few months ago

thanks

[TurtleWoods72]

Just out of interest Harvey, how old was the fuel, and was it pre-mixed or mixed prior to filling.

 

I have the DCS4301 which sat with premixed 95 Ron Tesco petrol and Stihl HP oil mixed 33-1 and it ran fine after two tugs following a year without use.