Block cleaning...Vat or Blast?

[miller]

Any opinions on that?

It's been a dozen years since my last rebuild. Now some of the machine shops use steel shot to blast the block clean. One even cooks it first, to powder up the paint, and junk.

Yeah, it looks good. Anyone have a block blasted, what are your thoughts on it?

Thanks!

 

[Seax440Dodge]

eh, I've always had mine hot tanked

 

[snakeoil24]

I can say being in the Chemical Induistry, EPA basically banned Hot tanking in many areas. The Shot peen and Blasting actually does a better job than a Caustic Wash, if they properly cook block first, Then blast. Finaly a Shot peen tightens the IRon block.

 

[Cranky]

Some shops here have a 'dish washer' machine that heats and cleans with with high pressure soap and water. They come out pretty nice looking. Had one shop owner tell me that an engine will never see a dirtier place than a caustic vat. He had one because that's what was available in the late late 50's when he bought his. He later replaced it with a 'dish washer' machine.

 

[Meep-Meep]

The pressure washers (dish washer) does a good job but no matter what method is used I recommend a follow up cleaning at home with oil galley brushes, laundry soap and hot water. The Zep industrial purple from Home Depot is good stuff also. Have a can of WD40 on stand by to wipe the flash rust off the machined surfaces. The hot tank was the best because the block was submerged in a hot caustic solution but still needed a follow up cleaning prior to assembly. Also, don't use the red rags during assembly. That rag lint gets everywhere and can cause issues if you're not careful. I actually use polyester lint free wipes during assembly of all critical components.

 

[69Bee]

First I wash the block in the JetWash. It will only get it so clean because the solution is safe for aluminum. A caustic solution will attack aluminum, whereas the Citrus Spray (brand I use) will not. I follow up the cleaning with a trip thru the glass bead cabinet. As long as you have ALL of the plugs out, and completely blow it out, it will be fine.

Some shops bake it in an oven for 4 or 5 hours, then put it into the Airless Wheel Abrader where it slings steel shot onto the block to clean it. The only thing with this is that you usually need to broach the lifter bores, line hone the mains, and deck the block in order to make sure those surfaces are proper. The steel shot impacting the surface has the ability to reduce the size of a hole because of the crater from the shot. Think of it as an impact crater with the outer ring being raised up. This type of cleaning works well, but requires more work to be done.

Dave
Precision Machine Servive

 

[miller]

eh, I've always had mine hot tanked

Me, too!
Great answers, guys. Really helped me make up my mind. Going with the vat job.

The blasting bit looks pretty and all that, but I'm familar with shot-peening, and know what it does to the steel surface. Not particularly wanted on machined surfaces, with close clearances. Also had one machinist tell me, if blasted with steel shot there could be a prob getting it all out, because of magnetism. Said best to use stainless shot...no magnetism.

Any rate, mine's going to the hot tank. Good old hard way. And plenty of scrubbing, brushes, soap and water. Maybe my old trick of 10% muratic acid (for any rust), and a coat of WD-40. Heh, my aching back.

EPA? No good for ****.