Husky 50 smoking where is shouldn't

[Seamus]

I have a Husky 50 which I have had from new. Cut a few trees but mainly used on through & through timber from the mill, so quite light use.

 

It has always been a good starter until this year. I drained the fuel out (I have read here that that should be done). When refilled (normal lead free) it then ran ok, but not an easy start.

 

I had to cut up an old fallen oak from the storms and it was having to work quite (had a new chain on it). Then noticed that smoke was coming out of the vents around the starter housing. Left it to cool down and after would not start again unless one of us held the throttle full open. It worked but would not idle. Next day it would not start under any condition.

 

Put in a new spark plug as I could not see a spark when I spun it over. Then suspected the ignition module so have replaced that. Got a spark but no start. Putting my thumb over the plug hole I can feel compression.

 

So now I am wondering where I should go next. I would appreciate any advice anyone might have.

 

Thanks

[spudulike]

I have a Husky 50 which I have had from new. Cut a few trees but mainly used on through & through timber from the mill, so quite light use.

 

It has always been a good starter until this year. I drained the fuel out (I have read here that that should be done). When refilled (normal lead free) it then ran ok, but not an easy start.

 

I had to cut up an old fallen oak from the storms and it was having to work quite (had a new chain on it). Then noticed that smoke was coming out of the vents around the starter housing. Left it to cool down and after would not start again unless one of us held the throttle full open. It worked but would not idle. Next day it would not start under any condition.

 

Put in a new spark plug as I could not see a spark when I spun it over. Then suspected the ignition module so have replaced that. Got a spark but no start. Putting my thumb over the plug hole I can feel compression.

 

So now I am wondering where I should go next. I would appreciate any advice anyone might have.

 

Thanks

 

Remove the muffler and take a look at the piston through the exhaust port - if the piston looks like someone has taken a coarse file to it and left it with bad vertical scoring, the saw has seized, if it is OK then lets look at the issue again!

[Seamus]

Thanks will do that. Came across a U-Tube video on that last night.

[Seamus]

Remove the muffler and take a look at the piston through the exhaust port - if the piston looks like someone has taken a coarse file to it and left it with bad vertical scoring, the saw has seized, if it is OK then lets look at the issue again!

 

I managed to get the muffler off after soaking it with WD overnight and have attached some pictures of the piston though the port. There does seem to be some scoring but don't know how bad you judge that to be. It does not look to be acceptable to me.

 

I am very unfamiliar with 2 strokes. All my experience has been with car engines. When I turn it over with the starter, plug etc removed it seems to latch at TDC. Though just thinking about it maybe that is when the coil lines up with the coil?

 

Would appreciate your thoughts on this.

[bellringer]

I am no expert but I would say that is badly damaged piston but might be wrong

 

 

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[C.J]

I have a Husky 50 which I have had from new. Cut a few trees but mainly used on through & through timber from the mill, so quite light use.

 

It has always been a good starter until this year. I drained the fuel out (I have read here that that should be done). When refilled (normal lead free) it then ran ok, but not an easy start.

 

I had to cut up an old fallen oak from the storms and it was having to work quite (had a new chain on it). Then noticed that smoke was coming out of the vents around the starter housing. Left it to cool down and after would not start again unless one of us held the throttle full open. It worked but would not idle. Next day it would not start under any condition.

 

Put in a new spark plug as I could not see a spark when I spun it over. Then suspected the ignition module so have replaced that. Got a spark but no start. Putting my thumb over the plug hole I can feel compression.

 

So now I am wondering where I should go next. I would appreciate any advice anyone might have.

 

Thanks

 

Did you put any oil with your petrol ?

[spudulike]

I managed to get the muffler off after soaking it with WD overnight and have attached some pictures of the piston though the port. There does seem to be some scoring but don't know how bad you judge that to be. It does not look to be acceptable to me.

 

I am very unfamiliar with 2 strokes. All my experience has been with car engines. When I turn it over with the starter, plug etc removed it seems to latch at TDC. Though just thinking about it maybe that is when the coil lines up with the coil?

 

Would appreciate your thoughts on this.

 

Its toast bud:thumbdown: That has laid down a coating of Piston aluminium on the cylinder and will need the cylinder salvaged if possible and a new piston or a new cylinder and piston. DO NOT just replace the piston, the cylinder must be that smooth, you feel no ridges etc with the pad of your finger - if you can, it will take the piston ring out on the new piston!

 

The reason for failure also needs investigating - common causes are bad/old fuel, leaking crankcase seals, split impulse/inlet manifold and incorrect H screw carb setting.

[Seamus]

Its toast bud:thumbdown: That has laid down a coating of Piston aluminium on the cylinder and will need the cylinder salvaged if possible and a new piston or a new cylinder and piston. DO NOT just replace the piston, the cylinder must be that smooth, you feel no ridges etc with the pad of your finger - if you can, it will take the piston ring out on the new piston!

 

The reason for failure also needs investigating - common causes are bad/old fuel, leaking crankcase seals, split impulse/inlet manifold and incorrect H screw carb setting.

 

Thanks for all the replies.

 

It has always been run with 50:1.

 

Spud

 

Thanks for the feedback.

 

I can just get my the tip of my little finger nail in there and can feel the ridges on the piston.

 

So the pot has to come off and am sure the cylinder will be scored so let's right that bit off. What do I need to look for in the crankcase that might be causing problems?

 

Bearing in mind that I am now retired and the saw will only be used domestically, I have seen that there are some 3rd party piston and pot assemblies available for the 50. Are these up to scratch (unfortunate phrase) for the use I am going to put the saw to?

 

Thanks

 

David

[spudulike]

Thanks for all the replies.

 

It has always been run with 50:1.

 

Spud

 

Thanks for the feedback.

 

I can just get my the tip of my little finger nail in there and can feel the ridges on the piston.

 

So the pot has to come off and am sure the cylinder will be scored so let's right that bit off. What do I need to look for in the crankcase that might be causing problems?

 

Bearing in mind that I am now retired and the saw will only be used domestically, I have seen that there are some 3rd party piston and pot assemblies available for the 50. Are these up to scratch (unfortunate phrase) for the use I am going to put the saw to?

 

Thanks

 

David

 

The cylinder may be ok, I have a 95% success rate on them but it is a bit of a job and takes a bit of know how!

 

The aftermarket stuff is what you pay for,some OK and some awful. The Hyway stuff seems passable but I try to salvage the OEM part and fit a Meteor piston if possible.

[Seamus]

The cylinder may be ok, I have a 95% success rate on them but it is a bit of a job and takes a bit of know how!

 

The aftermarket stuff is what you pay for,some OK and some awful. The Hyway stuff seems passable but I try to salvage the OEM part and fit a Meteor piston if possible.

 

Thanks - I will look those up.

 

I have now stripped it down so see what you think about it please.

 

I cannot feel any vertical play in the piston, con rod, big end. There is very slight lateral play, not the slide side to side, just very slight if you sort of try to bend the rod.

 

There is no play in the crankshaft bearings.

 

The piston ring is seized on the exhaust side, though I expect that would be expected. Would this account for the blow by creating the smoke via the flywheel?

 

Here are the pics. Exhaust is at the bottom in case anyone is not familiar with it.