550xp exhaust port

[Adamski]

Yep, if youve had it off and all is good then it should be fine. The nub on the end of the choke shaft that fits in the “v” of the master control lever was broken off. #12 is pointed right to the end that was broken off
View attachment 94925

All seems good to me

 

[Adamski]

Gonna tear it down tonight. Check for stupid anomalies like a sheared flywheel key etc etc... God knows why there would be on a 2016 saw.

 

[Moparmyway]

Did you plug the decomp ?

 

[Adamski]

Did you plug the decomp ?

No as I don’t have the correct pitch and thread size. But I removed it and it opens and closes like new. Can’t see any wear around the taper/valve either.

 

[Moparmyway]

I've had more than one or two fool me ...................

De plug is de mechanics best friend

 

[Adamski]

I've had more than one or two fool me ...................

De plug is de mechanics best friend

Agreed, But surely even with a slightly leaking decomp you would at least get the initial 'pufff'

 

[Onan18]

Agreed, But surely even with a slightly leaking decomp you would at least get the initial 'pufff'

Not always

 

[Adamski]

Not always

hmm. interesting.

Okies. I'll be going through it proper tonight. Plug the decomp, squirt down the port, pull it over and see from there. For a 2016 clean saw it must be something simple. (I hope)

 

[Adamski]

hmm. interesting.

Okies. I'll be going through it proper tonight. Plug the decomp, squirt down the port, pull it over and see from there. For a 2016 clean saw it must be something simple. (I hope)

and if I can't find a plug I am guessing my 2065 decomp will be the same thread.

 

[Onan18]

and if I can't find a plug I am guessing my 2065 decomp will be the same thread.

Yesp.

 

[Adamski]

Any bets on it being the decomp??? Lol

 

[Moparmyway]

Any bets on it being the decomp??? Lol

It pays to limit variables, and a decomp is allways a variable

 

[Mastermind]

View attachment 94929View attachment 94930View attachment 94931

All seems good to me

The choke pin is supposed to be above the spring.

 

[Adamski]

The choke pin is supposed to be above the spring.

10-4. That was probably me when I pulled it apart and then tried to take a picture holding them together with one hand. I initially thought the spring was to keep the pin in the hole, kinda like a trigger rod sitting on the throttle lever on 346's/357's etc..

Thanks Randy!

 

[Tor R]

The choke pin is supposed to be above the spring.

you got good eyes Randy
Dunno how many times I've knocked them together like this myself

 

[Tor R]

2016, your 550 has most of the updates the 550 has got over the years, included transfer covers, boot, top end, bearings, crank, etc.

Dont know if your done it yet, but p&v test is the first you should do, them 550's has several places they struggle, AT can compensate for alot, but its always nice to know where a leak is.
As Kevin has said, them decomp valves is also the first we remove when we has a troublemaker.

If this was mine (you already started to plan those steps already), I would simply pulled the top end, clean up the carbon, and you also get the chance to easily knock in an helicoil for the muffler bolt, and of course you get the chance to check if there is something going on inside on the same time.
It will only cost you a new head gasket, dont forget to use a tad sealant on the crankcase (front and back on the head flange), them Husky boys has not learned how to machine them 550 cases yet.

Most of the times I can build up one 550 from the bottom and it starts right up, a few times I has to get a carb reset.

 

[Adamski]

Something has been swallowed...

And the ring is stuck solid in the groove..

But the bore is clean.. can this cylinder be salvaged and get a new piston kit. Not sure what it has swallowed as the needle bearings are all sweet as.

 

[Onan18]

Something has been swallowed... View attachment 94959View attachment 94960

And the ring is stuck solid in the groove..

But the bore is clean.. can this cylinder be salvaged and get a new piston kit. Not sure what it has swallowed as the needle bearings are all sweet as.

I would run it.

 

[Adamski]

I would run it.

What flat the top down to remove the highs and do the same with and old piston for the squish band? At the least the groove needs a bit of work allow a new ring to move freely.

Surely compression would be lower?

Not sure what it has swallowed either?

 

[Moparmyway]

Dang if that dont look like a roller bearing

I'd cut the chamber to clean her up, then cut the base for 0.019 squish with the gasket. Slap in a new piston after carefully making sure the wrist pin bearing aint missing a roller