Yeah, make damned sure that you get all of the beads out of them when you're done. Main and rod bearings don't like them very much.
My neighbour owns a cylinder head shop and glass beads heads all day long,and I did a set of mine there, so guessing it's fine.
You just want to make sure they have been dip tanked first. You throw them in there with oil and grease on them your buddy will never let you come back. After you get done blasting them blow them out good with air while they are dry. Then before assembling the haeds I wash them out good with solvent and hot water, flipping them a few times. Then blow them out good again with air, flipping them a few more times.
Yep,good advice.People wonder why sometimes it takes me a little longer or think the price is higher than it should be.It's mostly because they don't clean the parts beforehand.Then you gotta do it.Can't put greasy stuff in the cabinet.Dyce is correct,your buddy will be P.O.'ed. I've done heads,just have to anally clean and then clean again.Sometimes that stuff appears like magic.
Yes, but just make sure the gaskets are scraped good. I didn't mention cleaning the bolt holes. Make sure the bolt holes are dry before you start blasting, or the beads will collect in the holes and stick. And be carefull when you blow the holes out. The beads can hurt, and you don't want them coming back in your face.
Glass beads don't affect cast iron much,if at all.Just dust the gasket surface if there is residue but if you tanked them that shouldn't need much.If it is being done bass ackwards as in a fresh cut seats,throw in an old set of valves.If it makes you feel better you can back off air pressure or increase distance.I really have not had any problems.
Basically, any critical machined surface(seats, guides, and gasket sealing surface) that is not masked will need to be recut. Blasted guides need to be honed. Tapped holes should not be blasted because the resulting finish promotes galling when a fastener in that hole is tightened As was already said, ALL media must be removed. Be especially careful about blind holes, oil passages, and bolt holes. I use a small tipped air nozzle. I blow out each hole with the tip inserted all the way to the bottom of the hole. You would be surprised how much contamination can be trapped there. Like a damaged thread surface, grit in bolt hole causes fasteners to gall in place. Be careful about your eyes, especially when blowing out the holes as described.
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