I picked up a wla engine (42wlaxxx on the side case but 44 markings on the bottom of both cases, soo, I'm assuming a 44 motor???)
Motor is locked up . don't know why. took off the front head and jug no problem. Rear head off but the jug won't move so the piston looks like it's stuck. Pulled out all the cams
Trying to figure out how to unstick so I can get the cases apart and start repairs. Thinking about some kind of steal ring that can be held in place by head bolts and then using a pully puller to push the piston down. (Piston is about at top dead center)
Hopefully I can break it free and push it out before I have to get rough with a hammer or something. I don't know how "Welded" the piston is but I tried wd 40 soaking for a couple days to no avail. Any thoughts on how to unstick that I might not have thought of?
I know I'm gonna need new pistons and a bore/hone job so I'm not worried about taking a screwdriver/chisel/hammer to the piston if needed but I'd prefer being as gentle as possible.
Also both pistons have a small " x " stamped on the top. Does this indicate 10 over pistons from a previous bore job??? (or standard piston???)
My last scooter was a 39 Indian scout so harley 45 is a somewhat new language for me. Help please.

 

WD-40 isn't enough for stuck pistons. Marvel Mystery Oil, ATF, and Kroil are all much better. Finally, heat the piston with a torch making circles from the center outwards over and over. The piston will expand against the cylinder and unstick the rings. I actually heard three 'tinks' when they freed up on my HD Sprint motor. Heating the cylinder isn't effective in freeing stuck rings, they just expand with the cylinder.

 

Thanks, I've got it soaking with Marvel now. I'll keep giving it a dip every so often to see if it's sinking in. pick up a butane torch tomorrow and give another try..

 

Great! Butane may work, but I used oxy-acetylene. Try MAPP gas if you are picking one up.

 

My recollection is that all war time WLA's carry a VIN# starting with 42, they never used 43, 44 or 45 except for WLC's I believe you see 43. So the belly numbers if matching but starting with 44 is OK. Left case around the crank will be two cast numbers, one is the same on all bikes, the other will give you year and month they were cast. Pics would help, good luck.

 

After more soaking and heat, I`d use my longest breaker bar on the sprocket nut
( Back and forth a bit at a time)

 

Drill some 1/2 inch holes in the top of the pistons then heat the piston it will move more

 

Well, I didn't think it would work but... butane, marvel, and tapping with a ball peen while constant pressure on the sprocket nut did it.

 

Dern I didn't think you could hurt an old flathead 45. The 1941 wla I had many many years ago you couldn't kill it, I road it hard and lent to several other people including my dad and nobody was harder on a motorcycle than he was. Sold to some Canuck in to early 80s and it was still running like a top.