Husky still won't start!

[Bosun]

I'm still having trouble starting my Husky 240. It won't even fire.

New plug (0.5mm), sparking OK, new fuel (although I've been using Aspen), sound electrical connections, new fuel filter, fuel primer OK, choke OK.

 

I've decided to look at the carb, unless there's anything else I should try first.

 

Are there any strip down guides out there? I don't want to take apart more than I have to.

 

Many thanks.

[spudulike]

I'm still having trouble starting my Husky 240. It won't even fire.

New plug (0.5mm), sparking OK, new fuel (although I've been using Aspen), sound electrical connections, new fuel filter, fuel primer OK, choke OK.

 

I've decided to look at the carb, unless there's anything else I should try first.

 

Are there any strip down guides out there? I don't want to take apart more than I have to.

 

Many thanks.

 

A working saw, in basic terms, needs compression, spark and fuel. Life is never quite that simple but it helps to check these things out.

 

If the saw has 150+ compression and the plug is sparking then the fuel system is probably at fault.

 

Is the plug wet with fuel after 10 - 15 pulls on the choke - it should be saturated!

 

It is possible that the metering arm is stuck open or the choke plate isn't sealing the carb properly plus there is a multitude of other things it could be such as split fuel lines and hardened diaphragms etc.

 

Is it time to give it to someone with experience?

[Stubby]

After you have pulled it over have you looked to see if the plug is wet ? If its not its fuel related ( not getting any ) If it is its ether no spark ( under compression ) or you have flooded it . I know you say it is sparking but it may not be under compression . If this is the case it could be the CDI unit . If you have flooded it maybe you are missing the initial " pop " when it fires ? Just a few thoughts .

[Bosun]

The plug is wet after a dozen or so pulls. Can't detect the initial "pop" as it fires.

 

What is the CDI unit?

 

Why might it not spark under compression, when it sparks with the plug out?

 

Sorry for the questions, but I'm trying to understand what's going on.

 

I'd like to fix it myself if I can, and hopefully improve my knowledge for the future. After all, give a man a fish and feed him for a day. Teach him to fish and feed him for life. Or words to that effect.

[peatff]

What is the CDI unit?

 

Why might it not spark under compression, when it sparks with the plug out?

 

Sorry for the questions, but I'm trying to understand what's going on.

 

The CDi is a capacitor discharge ignition (coil) on the other end of the HT lead bolted next to the flywheel under the starter cord side of the saw. If the spark is weak it may not be jumping the plug gap under pressure. Try warming the plug with a blow lamp and put a spoon of fuel straight down the plug hole and stick it together quick then pull it over no choke just to see if the spark is working, it should fire over a few times.

[adw]

These little saws did not really suffer with bad ignition units, if it has a spark at the plug it is probably ok. The starting procedure is very important, assuming everything has dried out, push the purge bulb as many times as it takes to 3/4 fill the bulb, pull out the choke, crank the engine only TWICE then push the choke back in, do not touch the trigger, crank the engine again, it should start within three pulls or there is something else wrong with it, they were quite prone to losing part of the bearing cage, this will nip the ring in down the transfer port side of the piston, this cannot be seen through the exhaust port, let us know how you get on, removing the carb needs to be done in the correct order, I can run through this if you wish.

[Bosun]

Thanks ADW,

 

After cranking the engine twice, should I push the choke in even if it hasn't fired? Also, when you say push the choke in, is that all the way in, or just to the intermediate position?

 

Presumably, losing part of the bearing cage will have caused some damage and affect compression? What compression pressure should I be seeing?

[Eddy_t]

Thanks ADW,

 

 

 

After cranking the engine twice, should I push the choke in even if it hasn't fired? Also, when you say push the choke in, is that all the way in, or just to the intermediate position?

 

 

 

Presumably, losing part of the bearing cage will have caused some damage and affect compression? What compression pressure should I be seeing?

 

 

There's no such thing as an intermediate position! Choke is on or off!

[spudulike]

Thanks ADW,

 

After cranking the engine twice, should I push the choke in even if it hasn't fired? Also, when you say push the choke in, is that all the way in, or just to the intermediate position?

 

Presumably, losing part of the bearing cage will have caused some damage and affect compression? What compression pressure should I be seeing?

 

The compression should be 145+, 150 is typical on a well used but healthy engine and 170psi is a very healthy reading on a run in engine.

 

Some saw types always read low and some high, a saw like this I would expect 150-170 on a decent engine and that is on a Gunson High Gauge, some gauges will only work corrctly on a car engine due to the type of valve in the gauge!

[Bosun]

There's no such thing as an intermediate position! Choke is on or off!

 

The 240 has a 1/2 choke position. Off-choke is set after starting when the trigger is activated.