Husqvarna chainsaw L65 get floaded won't start

[Jonny Vee]

I have had setting on my shed for long time an old Husqvarna L65 Chainsaw with tillston carburator.

Committed to get her running for some large tree, I cleaned up the carburator with new carburator kit RK23HS and started after few pulls. It then stopped and won't start anymore. The cylinder get floaded

I checked compression and still at 125 psi. Piston seems a thin score on muffler side and when cranking can see some fuel coming down from the top.

Is the engine gone or carburettor ?

Thanks

 

[Burnerman]

A good saw, this one and so long as you feel the compression as you crank it over it should be fine.
Lets start by getting the excess fuel out.
Take the plug out, invert the machine and crank it over - any excess fuel will spray out of the plug hole.
Try for a start after this, don't overdo the choke and if it does go, run it a while at various revs until it settles.
Just to remove the unlikely issue of a fuel tank ventilator being blocked, run the engine with the fuel cap slack for a while.
It's possible that the mixture adjustment screws aren't as they should be, so try this!
Set the tickover high, then turn the L screw in until the engine starts to speed up.......it will eventually stall so back it out again until the tickover speed starts to slow and then back in again a fraction.
For the H screw, the engine needs to be revving high....if it starts to 'four stroke' at high revs the mixture is too rich....too weak and the engine won't accelerate quickly. You'll only get the fine adjustment here when the machine is actually cutting of course.
Usually the screws are set at 3/4 of a turn out from fully in.
John

 

[Jonny Vee]

A good saw, this one and so long as you feel the compression as you crank it over it should be fine.
Lets start by getting the excess fuel out.
Take the plug out, invert the machine and crank it over - any excess fuel will spray out of the plug hole.
Try for a start after this, don't overdo the choke and if it does go, run it a while at various revs until it settles.
Just to remove the unlikely issue of a fuel tank ventilator being blocked, run the engine with the fuel cap slack for a while.
It's possible that the mixture adjustment screws aren't as they should be, so try this!
Set the tickover high, then turn the L screw in until the engine starts to speed up.......it will eventually stall so back it out again until the tickover speed starts to slow and then back in again a fraction.
For the H screw, the engine needs to be revving high....if it starts to 'four stroke' at high revs the mixture is too rich....too weak and the engine won't accelerate quickly. You'll only get the fine adjustment here when the machine is actually cutting of course.
Usually the screws are set at 3/4 of a turn out from fully in.
John

John,

I did try to remove the excess fuel inverting the machine and got load out of it. I plugged again no choke but after few crank it get floaded again and no sign of starting. I done this several time before giving up

What disappoint me is that it started at first time after carb clean up almost immediately and now not even a sing of start. Seems like it get flooded pretty quick

I remove carburettor again and checked if I have assembled correctly and can't see anything wrong with unless the metering diaphragm get stuck but can't check it while on the machine

Any idea?

 

[Burnerman]

If you are convinced that the carb is flooding, I can only suggest that the needle valve assembly is somehow incorrectly assembled.
However, controlling that is the metering diaphragm ( the one with the silver disc),
Do compare it with the original, especially the small central peg which must be the same length as the original.
John

 

[Jonny Vee]

John, back on this old saw only now due of lack of time. carb cleaned up again and needle valve seems to be okay.

What happen: I drain the fuel from putting chainsaw upside down and cranking several time. it then start and keep running even if not very well.

When it stops and you want start again, it won`t start and spark plug is always very wet.

I removed the muffler and can see the piston it is a bit scored. can this be the issued that get the saw flooding?

Can`t see any good replacement unless they cost a fortune and not really worth the gamble

 

[Burnerman]

For sure, any piston scoring is not a good thing - however, your saw does start so there is enough compression there.
Clearly, the saw is running much too rich - this accounts for a wet spark plug and raw fuel resting in the crankcase.
I don't know if you've tried this, but there are three adjustment screws on the Tillotson carb (as a rule).
One should be marked L for low speed running, one marked H for high speed running and finally a mechanical throttle stop screw (usually marked LA).
Try the L and H screws one turn out from fully in....if you've removed them at any time, please note they aren't interchangeable.
Failing this, I can only suggest a replacement carburettor, unfortunately - or a rebuild kit.
John

 

[Jonny Vee]

For sure, any piston scoring is not a good thing - however, your saw does start so there is enough compression there.
Clearly, the saw is running much too rich - this accounts for a wet spark plug and raw fuel resting in the crankcase.
I don't know if you've tried this, but there are three adjustment screws on the Tillotson carb (as a rule).
One should be marked L for low speed running, one marked H for high speed running and finally a mechanical throttle stop screw (usually marked LA).
Try the L and H screws one turn out from fully in....if you've removed them at any time, please note they aren't interchangeable.
Failing this, I can only suggest a replacement carburettor, unfortunately - or a rebuild kit.
John

John,

The carb has been cleaned up and rebuilt with new carb kit. Yes I removed the L and H screw and put those back one by one to avoid any mistake.

The currently both sitting at 1 1/4

Saw still got compression and start and run after it is drained. issue is when you stop and want start again that it look like flooded.

So you still believe this is a carb issue?

Thanks

 

[Burnerman]

Seriously, I can't think of anything else it could be.
Haver you tried running the thing with the petrol filler cap loose, in case there is some pressure there?
John

 

[lostinthelight]

It would be an idea to apply up to 7 psi into the carb fuel intake to see if it will hold pressure