The Cut Report - After the Bench

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Here's another, a 340 with 353 cylinder and HDA-198 carburetor mix and mashup that I did for fun.
Sad that this series of saws is no longer being supported by the manufacturer, they were fun while it lasted.

 

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As usual, it's been some time since something of interest has come across my workbench. Now, you wouldn't think this was anything new, as it's been out for some time now and I've already worked with this model, or so I would have thought. As it turns out, the Mark II 562XP's that first came out, had Mark I cylinders on them. Just like the last of the Mark I's had the new dished piston installed in them. So, having been a spell since the last new one I've done, this is the first "true" Mark II that I have come across as it turns out.
I'll start out by saying I really like what's been done to the saw and it runs and cuts quite well. There is very little that has not been changed and can be used between the first and second series other than the filtration system, which while still the same style and size has upgraded materials for better filtration, the Mark I's will benefit from this. The cylinder has all new timing numbers to it and a nice gap between the intake and the impulse channel, which will give more room for modification. the top has a handy dandy flat spot 90 degrees to the bore dead in the middle, which is super handy for doing machine work on the lathe. A thick base gasket is utilized pretty much ruling out a base gasket delete, without a new base gasket cut of a different material. Also, with the materials utilized it would be hard pressed to have a blowout being constructed of aluminum, rubber sealed and gasket layer, machining a tighter squish is best. While it has a beautiful looking band already, the band on this one was cut to help with "the numbers".
The lower transfers are the biggest design change being much more in line and bigger caps for better flow. The uppers look the same other than timed just a bit differently.
The muffler is also changed and once again, easier for the modder to do his/her thing.
The two most notable things that you will no longer get with the new version is a decompression valve and crank stuffers. Also, the piston is slightly dished as has been noted before.
As best I can ascertain, Husqvarna didn't hold back addressing the issues of the old version, so much so I think it could have stood to have a new model number designation even. As literally everything is new and different from the old from the cases, crankshaft, bearing and seals to an improved starter pully and all new plastics and handles.
Here's my iteration of the "true" Mark II 562XP...

 

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As long as I'm here I'd like to mention something about an old Mark I that might help someone else from getting snake bit like happened to me.
Received a Mark I with s bit of time on it for repair and porting. Saw shop tag said not running - fuel line. Upon inspection, it had low compression and a slight leak at the PTO side seal. Fuel system was checked and was fine. Saw had a stuck ring with damage to the piston and cylinder. There was no crank play so a new top end and seals, gaskets etc. were ordered. Upon installation of the seal I found out the retainer for the bearing was gone on the PTO side but the bearing balls were still spread out enough to keep the crank steady. Which, lets face it, puts this in a whole different light. I hatched a plan to change the bearing and ordered one, only to receive one from an earlier model, the others being unavailable. Decided to eat it and order a loaded crankcase and be done with it. Somehow this too got confused as I had gotten one for a 550mkII. This obviously wouldn't do. Finally got the right case and the ever so patient owner was kind enough to put up for the new case and all I had to put up was my time for my mistake when the right case set arrived.
Long story short, I will be removing leaking seals first from now on to assess the bearing situ.
For all the fun it gave me, I nicknamed this saw "the Joker".

 

[Tor R]

As long as I'm here I'd like to mention something about an old Mark I that might help someone else from getting snake bit like happened to me.
Received a Mark I with s bit of time on it for repair and porting. Saw shop tag said not running - fuel line. Upon inspection, it had low compression and a slight leak at the PTO side seal. Fuel system was checked and was fine. Saw had a stuck ring with damage to the piston and cylinder. There was no crank play so a new top end and seals, gaskets etc. were ordered. Upon installation of the seal I found out the retainer for the bearing was gone on the PTO side but the bearing balls were still spread out enough to keep the crank steady. Which, lets face it, puts this in a whole different light. I hatched a plan to change the bearing and ordered one, only to receive one from an earlier model, the others being unavailable. Decided to eat it and order a loaded crankcase and be done with it. Somehow this too got confused as I had gotten one for a 550mkII. This obviously wouldn't do. Finally got the right case and the ever so patient owner was kind enough to put up for the new case and all I had to put up was my time for my mistake when the right case set arrived.
Long story short, I will be removing leaking seals first from now on to assess the bearing situ.
For all the fun it gave me, I nicknamed this saw "the Joker".

When I have to go in depth on them, that is, unless the air leak is massive, when I'm going to pressure test I disassemble the tank, block in & ex pressure, and throw the powerhead in a bucket filled with water.
I've had 5-6 examples where the bearings weren't completely seated in the pocket and caused air leakage in the crankcase gasket. I'm not sure I would have found the problem without having the entire powerhead in water.
Cold pressing of bearings is a fantastic thing if you want unexpected problems....and short lifespan.

 

[Stump Shot]

When I have to go in depth on them, that is, unless the air leak is massive, when I'm going to pressure test I disassemble the tank, block in & ex pressure, and throw the powerhead in a bucket filled with water.
I've had 5-6 examples where the bearings weren't completely seated in the pocket and caused air leakage in the crankcase gasket. I'm not sure I would have found the problem without having the entire powerhead in water.
Cold pressing of bearings is a fantastic thing if you want unexpected problems....and short lifespan.

Finding the leak with a spray bottle of soapy water was no problem. Where I got in trouble was the bearing, usually when a bearing has the retainer missing the balls all fall to one side. That did not happen on this saw, so it kind of tricked me thinking the bearing was still okay. Not too long ago on a 3-series the flywheel side seal was leaking on the outside where it met the case. Must have been a cheap AM part or something as I put an OEM seal in and it cured the problem.
Heat is a wonderful tool at our disposal to use if we so choose to do so. Done properly it makes the job fast and easy with predicable results.

 

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A nice 353 conversion to 346xp NE for yours truly. Running here fat tuned for break-in @13,800rpm. @luckydad

It's a 90 degree July day here today and yet that video almost made my nose feel cold. Bonus points that it ain't shot vertical!!

 

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It's a 90 degree July day here today and yet that video almost made my nose feel cold. Bonus points that it ain't shot vertical!!

I suspect my nose was cold when I made that vid.