adw

The ser no. tag will , if still there, be under the top handle, where it screws to the bottom of the fuel tank, remove the screws and carefully pull the handle away from the tank to expose it.

What are you actually after?

If the saw had an auto deco valve and has been converted to manual, then check the rubber boot has not come off or split on the connection at the cylinder base, r/h side.

02 is the auto deco valve cylinder, this will sub to the 04 cylinder

Mucculloch consumer brand is handled by Husqvarna, in Newton Aycliffe, bolts breaking and blades coming off are the things of horror films, I would contact them and relay what is going on here before somebody gets hurt, don't go fitting non genuine parts as this will muddy the waters.

Slightly worrying that a blade comes off, so insuffiently tightened, blade bent or unbalance, bent crank causing in balance. Blade bolt in the book says 70nm.

The amount of drive links should not stop it running smoothly asuming there was enough adjustment left due to the extra length, is the sprocket worn? I guess it is a spur spur sprocket so should be changed when fitting a new chain.

I am sure I have some XP embossed decals Stubby if you want her to look the dogs.

But what about the compensator carb?

Have you not read this thread sir? You are not going to get it!

I have seen this before, the oil hose was shortened to stop the pick up filter rattling against the gasket from the inside, this in turn causes the gasket to leak.

An old trick is also to feed the pick up pipe through an o ring, this will hold the pipe further from the crankcase and increase the joint between the pipe and the pump.

Do not run the saw with the clutch cover, bar and chain not fitted, the clutch will spin off on the over run, be aware!

That is correct.

The 254 bar pad never changed, it is just the same on the 550 and 560 today, it must be a alignment issue with the Oregon bar.