Cleaning coolant passages?

[thriller]

So I have had my block stripped down and in the shed for a little while now, wondering the best way to clear the gunky cruddy semi-rust stuff out of the coolant passages? I've knocked out all the freeze plugs and spammed the garden hose to get the loose crud out, but there's still a bit of crap caked on. Is there a chemical solution or something I can do at home, or is it best to get the block (acid?) dipped? What would that roughly cost?

 

Also, 5 of the 6 cylinders still show the cross hatch honing marks. I can post up a photo of the one that doesn't if it helps. Would that mean I can give them a quick hit with a drill-hone-thingy attachment, double check the roundness+measurements, and start building it back up? Will be a stock build, might go a slightly bigger cam but I'm not trying to get this thing to boot hard.

 

Thanks for any help

[1600dave]

Soak it in molasses. Google it.

 

My grandfather used to use it to clean up old rusty tools that he'd buy at auctions and clearing sales.

[thriller]

Sister is into horses, she spilt the stuff in the back seat of mums 08 VW Passat. That went well.

 

Thanks for the tip! I'll look into it. Won't be fun to clean I guess

[KatoKid]

or take it to an engine shop and have them hot tank it. Proly $100.

[dat2kman]

Send it off for hot tank cleaning, then nutralising bath to stop acids eating metal, then thourogh cleaning.

If bores are fresh honed to suit the ring set you are using, then get it home, buy a set of rifle cleaning brushes a 5 litee bottle of kero, and of prepsol, some medical lint free wipes, and then clean it properly, even though you just had it "cleaned"

Wipes the bores with lint free, see how dirty they still are?

Thats the cutting solution from the honing process, ,, clean??, yeah ,, sure!!

 

Once assembled and fitted fill with water ONLY, fit a hole free sock into the top hose, ie as a particle trap, over thermo housing outlet, or top rad inlet, fit hoses etc, run engine, a few times, pull hose, ,,,, gee look at all the crud, flakes, silicone, and muddy gunk,,,, from a "cleaned" engine!

And we wonder why our radiators dont seem to cool as well!

Drain water, refill, do it again, drain refill, but this time use a mix of either Redline Water Wetter, or Penrite Din Coolant, i like to go about double strength on the mixture, follw directions on bottle.

 

I reckon your water passages will be pretty damn goid by now!