PCB350Z

I cleaned it with acetone and scraper then took 2k grit wet sandpaper to it and that didnt really do much. I cant catch a finger nail on any of it but i dont want to have to do this job a second time.

coletrickle74

iTrader: (1)

I've put together ones that weren't clean up that good. Should be good if you can't feel anything on it

dcains

iTrader: (15)

I'd get back to scrubbing, but use a scotch brite pad, and you should be able to get it perfectly clean. When I was a kid, late 1970's, I worked a Summer job in the race engine shop for Bob Sharp Datsun. My only job was to scrub the engine block cylinder walls with white towels and hot soapy water, until the towels didn't get even the slightest bit dirty. This was done to get the machining grit out of the honing marks. Ever since then, when putting engine parts together, I believe in getting them as clean as humanly possible, and if you can't feel it, but you can still see it, I'm still not done.

PCB350Z

Never ever take scotch brite pads to a critical surface. Aluminum oxide thats in the pads will destroy your bearings over time and cause low spots.

dcains

iTrader: (15)

I was talking about those plastic scrub pads, is there aluminum oxide in those? If so, you're 100% correct.

PCB350Z

Yes sir they do the call it ALOX which is aluminum oxide in a crappy brand name. its the reason why you cant use em on glass

thatv35guy

iTrader: (1)

I've always had the machine shop prep the surface while they hone the block, etc., why not just have the machine do it?

PCB350Z

Well originally i asked them too. Im using my GF's dads shop to rebuild everything and he has a race car that he needs to work on to make some race hes been signed up for a year now. The machine shop (NAPA Panama city,Fl) said it would only take a couple days. They took there sweet time and it ended up being 3 weeks and when i got my rods and block back they never measured the journals because the old bearings were still in the rods and the main cap bolts were finger tight instead of torqued down. At that point i needed the block back to get GF's dad off of our back since her suv had already overstayed its welcome.

Looking back i should have headed the warnings and took it to mullins machine shop in Panama City. Overall though i got the block surface pretty clean with 2k grit wet sanding and a straight edge and feeler gauge to maintain straightness.