is honda cast aluminum hit and miss?

well i decided to start to work on the fl250 cylinder that i want to water jacked
and it welds easy so easy i was surprised and all i did was hit it with a grinder to get the paint off other than that no prepping
but i have had other honda cast aluminum that wont weld worth a crap

tried to fix a cracked fin on other honda cylinders and they wont weld even with lots of prep work and preheating

My guess is yes their is a lot of difference in their casting quality you can see a huge difference between the Pilot cylinders that were cast with the 89 date on them and all the cylinders that were cast with a later than 89 date the aluminum even stains differently on the newer castings, same with the Pilot crank cases the lower the serial number the easier it is to clean the castings, its like the pores in the aluminum is tighter on the older stuff.

There's a big difference between quality from a case and a cylinder
Every case I have seen or welded welded fine

Its the cylinders that are more hit and miss

I know that honda changed the casting company between 89 and 90 that's why they are different....89 cylinders,heads and case are better quality than any of the 90 or later castings.....

That's good to know

Cylinders are poured cast, cases are injection molded not sure if they use a differ blend of aluminum for the cases that are injection?