Before we go any further this is a build of love. Certainly I will be out of pocket financially but hell I cant take it with me or more likely the missus will spend it...
Firstly a quicky about the saw differences between the 394 and 395.
The 395 is dual/quad ported whereas the 394 is single/dual ported.
The 395 use a different inlet manifold system, using the most recent clamp/rubber inlet boot system with external impulse. The 394 uses the plastic manifold that screws on and has an internal impulse.
Carbs are similar but are different! The 394 is non epa whereas the 395 is epa and also has a tail for the required impulse line. Both can be interchanged with minor work.
The carb undertray is different between both saws but can be interchanged with some mild modification as the fuel line hole and throttle cable are about 3mm different. Also the 395 has rubber carb mountings and the 394 is solid.
The crank is heavier on the 394 over the 395. The other difference is the 394 has a keyway for a woodruff key whereas the 395 has a slot and "inbuilt" key into its flywheel. Therefore you should use a matched crank/flywheel if you want a straight forward swap.
Crankcases,fuel tanks,clutch,oil pump,drive gear etc are the same or interchangeable.
So where do we start...
So a set of old crankcases help...
Talk nicely to a powder coater and flash cash and they end up like this...
So we now know that the oil tank breather doesn't like the powder coating and melts. The new one just presses in and a tap with a soft hammer on an internal steel sleeve once its in the desired position just swells the plastic to lock it in position.
So first things first cranks and bearings. I find it easy just to tap them on the crank using a hammer and socket method.
Now time for the heat and warm there bearing area of the crankcase quite well for a minute or so with the blowlamp. The bearing and that end of the crank just pushes in with hardly any pressure. As it cools the crankcase will close up and tighten on the bearing. I normally spin it once in a while as it cools (else you can get some tension build up and find the bearing will be hard to spin until it gets destressed using a few taps with a hammer)
Now time to fit the gasket. I normally hold it in place with the thinnest smear of gasket sealant, just enough to make it stick. Next repeat the heat with the opposite crankcase having the crankcase bolts handy. Once warm enough the crankcase goes on and screws put in and tightened up fairly smartish. Then hopefully it should resemble a bottom end....
Fit the oil pump feed tube and filter, just pushes in the hole!
Next a simple job of just tapping in and locating the crank seals. I find that on the 394/395 the nitrile ones fit better than the metal cased seals for some reason (never had this issue on any other saw tho)
The 394 crank has the woodruff key slot as you can see here.
So crank together, seals in. Next the woodruff key gets fitted, flywheel on, washer then the nut gets screwed on handtight.
Now half the 394/395 weak spark issues are caused by bad grounding of the ignition coil. I tend to clean up around the 2 mounting screws to help combat it. Not pretty but it works!
Then fit the coil. I use the card of rizzlas as ive always got plenty of them around handy
Then on with the new meteor piston....
Next spin the saw around and time for the new oil pump to be fitted. Also got a new bung to go in (doesn't really do sod all tho..
Next a washer goes on the crank
Then the worm gear get fitted
So the completed oil pump...
Starting to look a bit like a saw now. That's enough for one post me thinks...