husky 254 fast idle.

[carlos]

my 254 was not starting from a hot start, so i took the carb apart to have a look ( not sure why as dont really know what im doing) and didnt see anything obvious , now it is idleling fast and erraticly  and stalling?

just wondering if there is anything easy i can check, without making anything worse?

probably end up taking it to a repair shop as i have always struggled with carbs tuning etc, but as its holidays i would like to try and get it going.

thanks carl

[Stubby]

2 minutes ago, carlos said:

my 254 was not starting from a hot start, so i took the carb apart to have a look ( not sure why as dont really know what im doing) and didnt see anything obvious , now it is idleling fast and erraticly  and stalling?

just wondering if there is anything easy i can check, without making anything worse?

probably end up taking it to a repair shop as i have always struggled with carbs tuning etc, but as its holidays i would like to try and get it going.

thanks carl

Send it to spud .

[adw]

254 old school now, however if you have had the carb apart and now its worse then dare i say you have re assembled it incorrectly, so starting with the pump side ( single screw ) here we should have the diaphragm against the carb body first followed by the gasket then the cover, this is very important as on the diaphragm  there are two flaps, non return valves, these work against the carb body and stops the fuel just moving back and forth, obviously while under here make sure the screen is clean, the pump diaphragm should lay nice and flat and not curl up, onto the metering side, here the gasket goes against the carb body followed by the diaphram and lastly the cover, this diaphragm should also lay flat with good convolution, the center disc should not be bent in any way, the centre where it contacts the metering lever should not have heavy wear marks, the metering lever should be level with the sides of the carb, use a straight to show this, if its too high bend it down, if it is way too high this is probably due to the needles rubber tip being worn, for further test you need a pressure tester, if the saw was racing before you touched the carb this could be the throttle flap sticking, or an air leak in the engine.

[MattyF]

Clutch springs ?

[woody paul]

If it was running OK I would have checked simple things first before dismantling carb, fuel filter fuel line air cleaner and plug.

[Sawchip]

2 hours ago, carlos said:

my 254 was not starting from a hot start, so i took the carb apart to have a look ( not sure why as dont really know what im doing) and didnt see anything obvious , now it is idleling fast and erraticly  and stalling?

just wondering if there is anything easy i can check, without making anything worse?

probably end up taking it to a repair shop as i have always struggled with carbs tuning etc, but as its holidays i would like to try and get it going.

thanks carl

On top of the run down ADW posted for you ....when taking the carb apart , did you remove the 2 jet needles ( H and L) . If so or even if you did not they have a "basic setting" of "form lightly seated clockwise" and then back open by 1 1/2 on the H and by 1 1/4 turns on the L. 

[carlos]

thanks for all the replies, thanks for the detailed info on the carb ADW ill undo it again and check all that,

i didnt go near the tuning screws apart from turning the idle down a bit.

i dont think its the clutch springs as the engine is erratic, but ill look to be sure.

thanks again for the replies, on new years eve too!

[spudulike]

The poor hot starting may be that the piston has had a light seize dropping the compression. The last episode, first thing to check is that the throttle linkage isn't holding the carb open so you need to start it up and push the throttle valve fully closed and see what happens. You can also turn down the idle speed and if it runs with the idle manually pushed shut and the idle taken down then it looks like you may have an air leak. I take it that the gasket was OK and refitted? These older machines can crack the plastic inlet manifold where the bolts go through - seen it enough times.

Other than that, you may have cocked up on the carb rebuild.

[outinthewood]

Don't forget the tank breather behind the small "plate" above the fuel cap , it's secured by a single screw. I 've found over the years everyone forgets about this on the 254 and 242 also since they were prone to leaking fuel out when being transported a lot of guys bunged them up with sponge which for a good while would cause no problems but would as poss in this case the saw not to start hot but if you undid the fuel cap it would often start and run ok. 

[spudulike]

Good call on the tank breather but on the 254, it unscrews from the tank on the clutch side and you need to remove the AV mount screws to get enough movement between the tank and engine to remove it.