Would you inspect further? ?

[Crzybowhntr]

550xp.

 

[dall]

pressure and vac check ok ?

 

[T.Roller]

Yrs I would

 

[Crzybowhntr]

pressure and vac check ok ?

Don't know. I am assuming I need the block off plates to do the tests. I make them for my other saws but I'm not sure how a homemade version will work on these saws. They sure didn't work on my 576xp.

 

[paragonbuilder]

Looks like carbon scoring. That's auto tune right?

 

[Stump Shot]

I Always try and get to the why on a piston failure, and as already said pressure and vacuum test, after repairs made as well. It just saves future failures.

 

[jb-chainsaws]

In this instance I want to say no, however if it's a customers saw I'd do it as a matter of course.

Looks to be a poor tune and I agree with the carbon scoring comment above

 

[jmssaws]

Can you hang a finger nail in it or is it a rub

 

[Wilhelm]

That looks like the score mark I had on my PS-6400, carbon scoring in my case.

I replaced the piston kit and cleaned the cylinder @Mastermind style, put her back together and ran her hard ever since.

I did not do any vac/pressure test, I guess it is time to pull the muffler and inspect the piston.

 

[Crzybowhntr]

Yrs I would

Inside of cylinder. Nothing that even catches a fingernail.

 

[Crzybowhntr]

Looks like carbon scoring. That's auto tune right?

Absolutely.

 

[Crzybowhntr]

Can you hang a finger nail in it or is it a rub

Seems to be a rub. Wish it was a rub of Copenhagen in my lip but I quit 5.5 years ago.

 

[cus_deluxe]

Was it running right and you just happened to pull the muffler? Or low oncompression/running poorly?

 

[Crzybowhntr]

If I want to inspect the transfer gaskets, do I need to drill out the dimple in the heads to remove the bolts?

 

[Crzybowhntr]

Was it running right and you just happened to pull the muffler? Or low oncompression/running poorly?

I knew it had a score on piston upon purchase and happened to have time to remove for inspection.

 

[Crzybowhntr]

It would act as it was running lean from time to tim .

 

[cus_deluxe]

Should just be a "security" type torx bit right?

 

[T.Roller]

If I want to inspect the transfer gaskets, do I need to drill out the dimple in the heads to remove the bolts?

No they make special security bits for those. You should be able to find them at any tool store

 

[T.Roller]

Should just be a "security" type torx bit right?

Sorry missed this. Yes sir

 

[Crzybowhntr]

10-4 fellas. I'll most likely is the drill press and make my own security torx bit.