cylinder gunk ??

[75starter]

im tearin apart my 4 bolt main 350 out of my 75 jimmy and when i took the heads off all the cylinders were just caked with gunk and rusty stuff around the top of every piston this is my first engine rebuild my question too you guys is what would be the best way to clean the gunk out without scratchin the cylinders
the motor has been sittin for around 2 years its all crusty not soft enough just to wipe out

 

[MaxPF]

You're gonna rebuild it, right? Let the machine shop hot tank it and you won't have to worry about it

 

[4X4HIGH]

If you're going to rebuild the engine then the machine shop is going to boil the block clean and inspect for any cracks then bore the block oversize.

 

[Mountain_man]

Stop using Pennzoil

But yeah have them hot tank the block for best results

 

[75starter]

i gotta take it down to just the block right i have to take the pistons out and all this nasty gunk im afraid is gonna scratch the cylinder walls when im slidin the piston out the top plus it doesnt even look like theyll budge till i clear the way a little bit just lookin for a good trick to get the pistons out easy there quite a bit of build up on some when u rebuild do you have to bore it oversize ???if so can i just go for it and slide them out with a little persuasion and not worry about dammage to some extent

 

[4X4HIGH]

When rebuilding the cylinders get bored oversize, when overhauling the cylinders usually just got deglazed (honed). Just slam them out and don't worry about the cylinders, they'll be fine for the overbore.