Saw wont keep running

[mike68]

After setting the idle screws as per my previous request for help.

The saw , a homelite will start but fails to run.

When you prime it and start it it runs for what seems like the amount of fuel it has been primed with and then cuts out.

Squeezing the trigger does nothing.

I have pulled the fuel pipes from the carb and ,using a syringe sucked fuel through from the tank, so I don't think its a blocked fuel pipe.

I know the saw is worth nothing but I would like to get it running if I can for a sense of personal achievement.

Any thought or suggestions would be very much appreciated.

 

Cheers

[spudulike]

After setting the idle screws as per my previous request for help.

The saw , a homelite will start but fails to run.

When you prime it and start it it runs for what seems like the amount of fuel it has been primed with and then cuts out.

Squeezing the trigger does nothing.

I have pulled the fuel pipes from the carb and ,using a syringe sucked fuel through from the tank, so I don't think its a blocked fuel pipe.

I know the saw is worth nothing but I would like to get it running if I can for a sense of personal achievement.

Any thought or suggestions would be very much appreciated.

 

Cheers

 

The carb should have a cover on it usually held in place with a single big screw, take this cover off and check the gauze filter that is pushed in to the body of the carb.

 

It will look like a recessed hole about the diameter of a pencil and at the bottom of it, there is a gauze strainer that often gets clogged with small particles that wash through from the fuel tank.

 

If the saw has been left standing for a long while, it is possible a scum has formed and dried on this filter so it is worth removing using a small craft knife on the upturned edge of the gauze.

 

If it isn't this, it may well be the metering arm height in the carb under the other cover. Remove the cover, remove the diaphragm, lift the metering arm around 1mm and reassemble - the arm should generally be in line with the outer body of the carb or sometimes flush with the floor of the metering section of the carb - it will be pretty obvious when you get to lok at it!

[mike68]

THanks for that I will have a look tomorrow ( am in Oz)

 

I did take it apart today and give it a clean as it was full of Sh**e around the carb .

There are two fuel pipes on the right hand side of the carb as you look at it. the lowest one which is slightly lower and forward of the other is fed by the primer bulb.

the top one, I presume is fed from the fuel tank, i was unable to blow through ?

blockage?, as i said previously the actual pipe from the tank is clear.

Also when i push the primer after a few pumps it gets very hard to depress, should this be the case?

BTW the bar and chain have been removed .

[spudulike]

As the bulb fills with fuel, it will become more difficult to depress!

[adw]

Are you sure you have connected the pipes the right way round on the purge, they normally pull fuel from the carb, into the bulb and then back to tank, not done much with Homelite, but purg bulbs will normally have a short and a long connection, the longer one is normally the pressure side so this should be the return to tank ( not the hose with a filter on the end ) the short one is the suction side so this goes to the carb, the connection on the carb closest to the metering side diaphragm cover, if they are connected wrong it will try to push fuel into the carb.

[mike68]

As the bulb fills with fuel, it will become more difficult to depress!

 

Yes.... having reread my post I did appear to be a bit of a dipstick!

What I meant was it becomes impossible to depress , as though there is nowhere for the fuel to go , if that makes sense.

 

Also the fuel pipes into the carb are different sizes , so can't get mixed up.

Edited September 2, 2015 by mike68

[adw]

If you have connected the pressure side of the purge to the fuel inlet on the carb it will be impossible to push the bulb in as you are pushing against the inlet needle

[mike68]

Driving me nuts now!!

took carb apart (should have taken pics!)

There was a very small bullet shaped thing under a "see saw" with a spring on the opposite side . The cone shaped bit was dirty so ..cleaned it.

 

the fuel pipes are different sizes so surely I cant mix them up!

put the saw back together and it started first pull......then died.

 

it is a friends and he isn't too bothered if it gets running but I need to make the f'in thing run! its a matter of principle!

[spudulike]

Driving me nuts now!!

took carb apart (should have taken pics!)

There was a very small bullet shaped thing under a "see saw" with a spring on the opposite side . The cone shaped bit was dirty so ..cleaned it.

 

the fuel pipes are different sizes so surely I cant mix them up!

put the saw back together and it started first pull......then died.

 

it is a friends and he isn't too bothered if it gets running but I need to make the f'in thing run! its a matter of principle!

 

The see saw and bullet is the needle valve and metering arm, I hope the spring has been replaced correctly!

 

Have you just given the H&L screw a half turn counter clockwise? Sometimes this can get the saw going again!

[mike68]

So I took the saw to bits and cleaned it( wiped with an oily rag)

took the carb off and turned the fuel pipes around.

It now runs but only when the choke is out!!

Starts great but when i put the choke in it dies.

I think my next move will be to try a carb kit or it may well end up being an anchor for the canoe when we go fishing!!

Any further thoughts welcome???