what are the do's and don't when rebuilding a 046

[whatwas]

I'm a bit of a lurker on this site but have always been impressed with the knowledge of FF members.
I have 3 034's and really like them. I cut  about 30-40 cords (face cord)of fire wood per year, 90% beech and use a saw around my bandsaw mill here and there.
 I was at a estate sale and the guy had a 034(no bar/chain) with "unknown issues" and said he wanted $20 for it. I jumped on it as a parts saw, than he said you may as well take  that one too  and it turned out to be 046 with a tag from a small engine shop hanging off it saying piston scored bad. When I pulled the muffler (bolts were still loose from the shop guys) the piston is shot. 
So here's the question....Knowing I really don't make a living with a saw, would you rebuild with OEM piston/cyl only or go aftermarket. 
I'll be pulling it apart this aft to have a look at crank etc.

[mike_belben]

You can wreck an oem cylinder just as fast as a chicom.  The oem will cut wood the same and drain your wallet faster.  

If your wallet is particularly full and/or you prefer supporting non-chinese workers, there are plenty of vendors in the US selling good aftermarket parts for a bit less than oem.


Be warned.. A $200 topend kit will live 20 minutes if its got a bad set of crank seals or intake leak or base leak.  The only way to be SURE..  Is to vacuum and pressure test.  And its a pain.

[Woodcutter_Mo]

 There are some fair quality aftermarket piston and cylinders. Meteor from what all I've read is a good fair priced aftermarket brand for the piston and cylinder. I used a meteor piston and rings kit in my 024 with oem cylinder. 

 Go with oem seals and hoses if they need replaced. 

[whatwas]

Thanks for the advice, as far as draining wallets, I've pretty much got that mastered.
From what I've read  you can  put a big bore kit in for the same money and have a saw equal to 066 (close anyway) ........ is the 046 bottom end up to it. 

[ZeroJunk]

Thanks for the advice, as far as draining wallets, I've pretty much got that mastered.
From what I've read  you can  put a big bore kit in for the same money and have a saw equal to 066 (close anyway) ........ is the 046 bottom end up to it.

People smarter than me say that the big bore without the increase in crankcase volume doesn't accomplish much.

It is unlikely that the cylinder cannot be cleaned to an acceptable level with some muratic acid and fine grit sand paper. Then you only have the cost of a piston.

[ButchC]

For every answer that says do it one way another person will say they do different and it works fine. That's not a knock on other opinions but saying there is more than one way to skin a cat.  I have used after market kits with zero problems. Some say that power is down with them but if so I cannot tell it on the handles. As said most of the time the cylinder is fine, clean the aluminum off with acid and reuse it.  Unless it is next to new the saw comes all the way down if I do the work. I install new crank seals, check the main bearings, put a kit in the carb, hoses etc, check the boot carefully. Such things are cheap as compared to doing the job 2-3 times and dont take that long to do nor require a big wallet.
  A saw like an 046 is worth putting some time and effort into  and for the part time user will last a very long time if kept tuned correctly.

[mike_belben]

I only buy saws in pieces and do full overhauls, never buy oem parts, port everything and they always rip.  

[joe_indi]

A 046 is worth rebuilding if your purse strings are not too tight.
More than just replacing the piston or top end, it is important to find and rectify the cause of the current seized piston.

A photo of the piston and the cylinder would help in that.
And while you do that fill the crank case to the top with a not-too-volatile liquid, kerosene, diesel or paint thinner. Look for any drop in level and corresponding stains on the outside.
Wriggle the crankshaft with the clutch drum removed, to check for bearing or bearing seat issues.
Check the current carb setting of the H and L screws, they should not have been turned out less than half turn from stop.
Also check the pickup body in the fuel tank. Is it blocked.
Examine the seating areas on the cylinder and crankcase. If there was a leak it will be indicated by a clean shiny appearance.

[whatwas]

one pic is the intake side of piston and cyl and the ugly side is exhaust, spark plug has good colour. I removed clutch and flywheel to get a-feel for the bottom end and it feels good but since the gasket kit includes bearings and seals, why not replace them.

 

 

[mike_belben]

Too lean leading to too hot is about the only thing that kills a jug.  Overhaul it, presssure and vacuum test it, reassemble and tune it.  Then dont beat the bag out if.  If youre bucking 30" rounds, let it idle a second between cuts while you do something else.  And dont run full throttle for three mins then shut it right off.  I see that all the time.  

 if the fan aint runnin the jug aint coolin. 

[joe_indi]

one pic is the intake side of piston and cyl and the ugly side is exhaust, spark plug has good colour. I removed clutch and flywheel to get a-feel for the bottom end and it feels good but since the gasket kit includes bearings and seals, why not replace them.

  

 

The cylinder will survive, The piston would need replacement,
.
What is puzzling is the clean deposit free cylinder top. That usually happens when the clutch side starts to draw in air (and chain oil) either from a leaking oil seal or a crankshaft shake, or a combination of both. This would cause the idle rpm to climb and usually the carb settings are used to compensate, often in correctly by closing down the L and H screws.

[welderskelter]

If you still need a cylinder for that 046 I made a mistake when I bought a big bore for my 066. I ordered the wrong one and didnt realize it until I had paid for it. No turning back with the Chinese. I still have cylinder, rings. piston and wrist pin. I could let it go cheap.