Not sure how to judge this cylinder and piston

[chopper88]

So I pulled apart the 562XPG I bought, knowing it probably had an air leak.
This is a running saw, with an idle problem. Unfortunately I have no means of testing compression, so pulled it apart after a failed vac/pressure test (clutch side seal is leaking).

I'm not really sure how to judge this. Knowing how nasty the saw was, crud was probably ingested through the intake, and it also seems there's blow by, possibly due to a worn piston ring?
Previous owner says saw has about 250 hours on it. All stock.

I was kind of put off by what looks like a little scoring and some marks in the cylinder, even though they can't be felt.
Apparently everything nasty was exactly out of sight when looking though intake and exhaust ports...

How would you proceed from here?
I want to clean piston and cylinder and put a new ring in at minimum but not sure whether that's enough, or that I need to sand piston and/or cylinder, or possibly even need to put a new piston in it? Not sure how 'worn' this would be considered since the grooves on the skirt seem mostly gone to me.

Exhaust side

Intake side

Some side views (Sorry about bolt being in the way, but I guess it's clear enough)


Intake side

Exhaust side

Intake side

Exhaust side

 

[blsnelling]

No way would I replace that. Clean it up and put oi back to work. Check the transfer port covers, case bolts, and crank seals for leaks.

 

[cuinrearview]

I'm not even sure you'll gain much with a new ring. The pics aren't the best but that assembly looks pretty good to me. Maybe a little wear on the intake side from ingesting some crud.

 

[chopper88]

No way would I replace that. Clean it up and put oi back to work. Check the transfer port covers, case bolts, and crank seals for leaks.

Thanks! That's reassuring.

This is my first 'saw rebuild' if you want to call it that.
I'm familiar with all sorts of 2 stroke engines, but they generally live in nicer conditions or were built from scratch with all new parts (string and hedge trimmers and a ton of tiny 70/80cc racing engines), so have a hard time making a judgement here on the 'lines' on the piston and cylinder. Also must confess, I've never actually worn out a piston.

I didn't check the case bolts for leaks, but that's a good one, I'll do that as well when it's back together again.
Rest seems OK except for clutch side seal, I already have a new one. Hoping to put everything back together in a week or two.

 

[chopper88]

I'm not even sure you'll gain much with a new ring. The pics aren't the best but that assembly looks pretty good to me. Maybe a little wear on the intake side from ingesting some crud.

Yeah sorry about the pics... turned out pretty dark while they looked clear enough on the phone.
If you want to see specific pics of something, let me know. I'll break out the DSLR.

Also thanks! And agree on the crud.
I didn't take thorough before and after pics, mostly took some quick pics for myself to have an overview of how things are put together without having to grab the manual every time I forgot something.
But this will probably give an idea on how dirty this saw was. Check out the crud in the corner of the air horn, the entire thing was filled with this.

 

[Mad Professor]

After looking at the first post, before I read the comments, I thought the saw had lived on a diet of dirt at some point. I see some others concur.

Any crud visible in carb intake?

 

[chopper88]

After looking at the first post, before I read the comments, I thought the saw had lived on a diet of dirt at some point. I see some others concur.

Any crud visible in carb intake?

No, not in the carb itself. But have taken it apart and cleaned it anyway.
Entire saw was generally full of junk though. So much that starting it wasn't even an option for me. The ratio of working on vs cleaning is about 1:10 until now I guess.
The before pic of this was AFTER I took an air gun to it.

 

[Deleted member 117362]

Just my two cents. Clean it up, replace ring (they are cheap), new base gasket, vacuum check and run. May want to take to a dealer and have updates done and they will be able to tell you how many hours on your saw, starts, idles, max rpm and fuel quality used. Just purchased a new 562 and Husqvarna is using a gray sealant on base gasket similar to Motoseal or Yamabond as seen in Tim's build. I just can not leave well enough alone, removed bolts one at a time and used blue locktite. They are also doing something different with fasteners and man are they installed tight. My plan, when it cools down and oak wilt spreading is at it's low point. Is to compare stock vs muffler mod vs ported 562 timed cuts with same bar, chain and log.

 

[chopper88]

Just my two cents. Clean it up, replace ring (they are cheap), new base gasket, vacuum check and run. May want to take to a dealer and have updates done and they will be able to tell you how many hours on your saw, starts, idles, max rpm and fuel quality used. Just purchased a new 562 and Husqvarna is using a gray sealant on base gasket similar to Motoseal or Yamabond as seen in Tim's build. I just can not leave well enough alone, removed bolts one at a time and used blue locktite. They are also doing something different with fasteners and man are they installed tight. My plan, when it cools down and oak wilt spreading is at it's low point. Is to compare stock vs muffler mod vs ported 562 timed cuts with same bar, chain and log.

OK, so 3 for 3 on just cleaning and not replacing/sanding piston.
I already have a new clutch side crank seal, piston ring and base gasket here and was planning exactly what you're suggesting. Now all that's left is cleaning cylinder and piston, pulling the seal and waiting for the seal install tools (on backorder for a few days). Then I can put everything back together.
I also noticed a tiny bit of sealant indeed, do you reckon it'll be necessary to re-apply it? I could barely see it, nothing like your picture. Have some Loctite 5926 here if needed, which will probably work as well.

Have been thinking about seeing a dealer to get it updated and get some stats, but on the other hand I'm thinking "If all is well, all is well".
Not sure yet, but guess I can always do that after all.

They keep updating this saw for some reason(s) indeed. Also noticed it now comes with a cutout in the top cylinder cover. I made sure to get at least a 2015 model, to have an EL48 and a 6 screw case as those seemed to have solved biggest problems so far. I wasn't planning on putting Loctite on case bolts, but might be a good idea to check torque settings now I'm at it anyways.
Enjoy your new (and old) 562(s)!
It's killing me to finally own a pro saw and never even having started it, can't wait to pull that rope for the first time!

 

[Deleted member 117362]

That cut out in cover is to remove heat from under it. Make sure to check for leaks as stated by Brad. Tree service friend traded in two T540's and two 562's and I just couldn't pass up a good deal on a 3rd 562 added to it.

 

[smokey7]

One thing to be sure of is the main bearing on the clutch side. Since you are having a leak there on a fairly new saw id be sure to inspect the bearing retainers and races not spinning in the case or on the crank. The only 2 562s ive worked on both had bad crank bearings at roughly 1 or 1.5 years young. Both had the plastic retainers/spacers broken apart and bearings all bunched up on side.

 

[chopper88]

One thing to be sure of is the main bearing on the clutch side. Since you are having a leak there on a fairly new saw id be sure to inspect the bearing retainers and races not spinning in the case or on the crank. The only 2 562s ive worked on both had bad crank bearings at roughly 1 or 1.5 years young. Both had the plastic retainers/spacers broken apart and bearings all bunched up on side.

Yeah I've seen that as well unfortunately, really hope it's not this that's happened... Read about it on another forum while doing some searches on the crank seals.
A package with the remainder of my order is on it's way here, I hope I'm able check out the bearing and replace the seal this evening.

On a side note, I F'ed up last night when removing carbon from the head...
Used a die grinder with a tiny brass brush attachment, and somehow the brush broke apart on the grinder side I suddenly heard a loud ping, and my stomach turned instantly. The 'stem' that holds the brush was bent and the brush was sitting at a 45 degree angle or something. Still don't have a clue how this is even possible, purposely ran in it on a low RPM setting to prevent me from screwing up something.

Now I have 3 'gouges' in the wall, very small, and well below the exhaust port but one seems through the plating. Ran a small piece of maroon Scotchbrite through it by hand (+- 15/20 sec) to remove any high spots.
Do you guys think this going to be a problem?


Bottom right gouge seems bad in first pic, but is actually looks best close up.


Highly magnified close up of first gouge.


And the culprit which caused this... (I cut the bent piece off, and used it further to clean up the exhaust port)

 

[jltrent]

Cleaning and new ring.

 

[chopper88]

Cleaning and new ring.

Ok, also after seeing last pics with the gouges?

Piston did clean up nicely:

 

[blsnelling]

Just make sure there are no raised areas around the gouges.

 

[chopper88]

Just make sure there are no raised areas around the gouges.

Thanks again sir! Happy to hear that coming from someone like you!

Do you have a preferred way to resolve and check something like this?
Like I mentioned, ran some maroon Scotchbrite through it by hand, it feels smooth when dragging my nail across but can't be 100% certain.
Was thinking about ringing the piston, lubing it up and carefully moving it up and down in the cylinder to hear and feel if it catches on something.

In the mean time rest of the parts/tools came in as well, hopefully I'll have some time to spend on it this evening.

 

[blsnelling]

Use a ring to see if it catches.

 

[chopper88]

And the saga continues...

Pulled the clutch seal, bearing looks good, but when turning the crankshaft I found this stuck to it, which seems to be part of the bearing cage:

Oddly enough, no damage/dirt anything can be seen from inside. Just this bit stuck to the crankshaft.
So I guess the case needs to be split to check and/or replace a bearing. This saw isn't bringing me any luck
I don't have the tools to do this, and don't want to invest in them as I'll probably only need them once.

Contemplating what to do now. Making some sort of tool, contacting dealer and seeing what the options are when I bring him the saw fully taken apart, searching for another case or another saw...

 

[chopper88]

It's now at the dealer, he'll split the case and inspect/replace bearings for max. 1.5hrs of labor + part costs.

 

[chopper88]

And the saga continues once again.

Dealer mangled a crank stuffer and had to order that as well, so it took a little longer.
One of the bearings was indeed broken, and the other was sort of corroded onto the crank, he showed it to me.
All in all I think it was a good call to have the bearings replaced.

But then...

So I got a call on Friday that it was done, I picked it up and installed the piston and cylinder right away.
Did a vacuum/pressure test which once again failed; a small leak under the base gasket where the case halves meet.
I applied some Loctite 574 with a toothpick under the base gasket and reinstalled the cylinder, waited 24 hours and did another test, which again failed.
The cylinder is now properly sealed all around, but it turns out there is a huge leak on the bottom side where the case halves meet as well.

Going back to the dealer tomorrow, since this is their work. This time I'm planning to leave the tank, piston and cylinder there as well, so they can vac/pressure test themselves.
Will probably lead to an interesting discussion on the cost of this work, I wasn't planning to pay again, as I've already paid for a leaking crankcase the first time...

This saw will run again, but I do not know when