Husqvarna 450 Issues

[mash55]

Full disclosure... I do not have much experience with engines but I am learning as I go.

I have a Husqvarna 450 which served me well so far but (basically) over night started to deploy white smoke out of the exhaust and bogged down/died when throttling up.
- I replaced the fuel filter, spark plug, air filter, drained fuel and used fresh 50:1 mix, cleaned the spark arrester.
- no improvement when starting up
- removed the exhaust muffler/heat deflector and cleaned carbon residue from all the components... lots of oil dripped out
- tried to clean it out as good as possible but its hard to do since its just one solid unit.

So I am thinking it could be the crankshaft seal?

Also looked into the cylinder to see whether there is any damage before beating a potentially dead horse. I attached a few pics and hope somebody can advice me whether that is normal wear/tear or whether I have a bigger issue.

Thanks

 

[Bob Hedgecutter]

Best indicator of abnormal wear is of the piston as viewed through the exhaust port- rather than bore scope of the cylinder walls.
I will admit to not having a great deal of love for the Husqvarna 4## series- they are somewhat of a consumer grade saw- not meant for heavy use, nor cost effective repair.

White smoke? Usually associated with water in fuel. In other formats- you would suspect coolant entering the combustion area- like a blown head gasket. In a chainsaw, especially with corn based fuel- separation of stored fuel.
If you suspect an air leak, pressure and vacuum test would confirm- or the redneck "spray all the suspect areas" while the saw is running and see if it stumbles or dies.

Hard to say, lot of conflicting information- white smoke- unusual, excessive oil in muffler, carbon build up- but the top of the piston is clean as a whistle.

Could be as simple as bad fuel needing flushed out and run until system clears. Serious air leaks cannot be tuned out, saw will rev high and turning mixture screws tend not to alter that.
Internals of cylinder do look kind of dry and possibly has been heated- like working hard with a dull chain.

 

[mash55]

Thanks for your reply Bob,

> Internals of cylinder do look kind of dry and possibly has been heated- like working hard with a dull chain.

I am certainly guilty of that

> Could be as simple as bad fuel needing flushed out and run until system clears

I will start here and hope for the best... and then move on to 'redneck... spray all the suspect areas' option (unless one of my neighbors has a pressure gauge.

Will report back over the week-end.