268 still wont go

[spudulike]

saw will fire on choke when cold,then just floods up,checked and double checked diag and gasket sequence,not touched welch plug,tons of compression,tried starting with throttle wide open all to no avail

 

If it fires on choke then it will probably be the needle valve - on some carbs, the metal central nipple on the diaphragm actualy pushes on to the needle arm - it will be horse shoe shaped if it does - worth looking at!

[miker]

yeah its a tillotson carb, maybe i havent got the nipple in right,think ill check the needle valve for wear while its apart,will update you tomorrow,cheers

[spudulike]

yeah its a tillotson carb, maybe i havent got the nipple in right,think ill check the needle valve for wear while its apart,will update you tomorrow,cheers

 

I had this on a 535 Jonsered with a Walbro carb but believe yours may have the same type of diaphragm - best to push the diaphragm in the middle so it looks like one of Madonnas tities and hook it on the needle arm and then position the cover - easily missed as most modern carbs don't fit the diaphragm this way!

 

By the way - I always accept payment in beer if offered:001_tt2:.....ot firewood:thumbup:

[Maico490]

With the Tillotsons very similar carbs sometimes have the diaphragm that hooks over the metering lever and some have the more normal type that just presses on it. The bloke at Rowena Motors is a real mine of info for these sort of probs and seems to carry every carb kit made since the earth cooled.

[spudulike]

With the Tillotsons very similar carbs sometimes have the diaphragm that hooks over the metering lever and some have the more normal type that just presses on it. The bloke at Rowena Motors is a real mine of info for these sort of probs and seems to carry every carb kit made since the earth cooled.

 

Yup - thats what I said/meant, sometimes this fact is overlooked, the nipple then pushes continously on the arm and causes the engine to flood.

 

Hopefully Miker will sort it out with our diagnosis!

[Maico490]

Spud, I got called away to the phone just as I posted and didn't notice that I had pretty much repeated what you said. Hopefully it may solve the problem but then again there are also those million and one other little things that come along to try you. My favorite lately was pressing a front wheel bearing in the wrong way round and then having the ABS light come on. Sensor gets it's signal from a little magnetic strip on the bearing. First bearing was £42 from the interweb. Second one £78 because it was a Bank Holiday Sunday. Happy Days

[spudulike]

Yup - all been there, no worries from my side - just shows we both share the same idea as to what could be wrong - Hope Mike is succesful in getting it going!

[miker]

right tonights update, checked needle, seems ok, made sure diag nipple is in the lifter, now it wont even fire...4 pulls on choke and i have fuel running out of the muffler..aaarrrggghhh

[spudulike]

right tonights update, checked needle, seems ok, made sure diag nipple is in the lifter, now it wont even fire...4 pulls on choke and i have fuel running out of the muffler..aaarrrggghhh

 

Got to be a leaking needle valve then - that will allow fuel to run freely through the carb even with the throttle closed.

 

Have you set the needle metering lever at the correct height - the saw shouldn't be pissing out fuel after four pulls???

 

If the saw is flooding - remove the plug and turn it upside down and turn it over - if you are brave you can fire the fuel off with a blowlamp but be prepared to lose your eyebrows:thumbup:

 

That'll clear it out!

[miker]

set metering lever level with top of carb body ??