So, today was time to clean the holes out... The manifold bolt holes (I have only 2 studs and the rest are 10mm bolts) then the head bolt holes. I have a bolt with a hacksawed slot down it that acts as a tap without actually cutting any metal, so when I could screw that fully in and out by hand I knew the threads were clean. There can be a lot of tarry shit and dirt down a hole that you just never see, but it can stop the bolt tensioning up on the head or manifold. It takes a few tries to get the slotted bolt in and out without filling the slots up with rubbish.

 

I measured a headbolt height in the block and the head depth just to make sure that the bolt would pull the head down without bottoming, you just never know... 3mm of extra space after skimming half a mm off the head.

 

Then I tipped the block upside down on two bits of wood and banged it up and down a few times. Unfortunately I vacuumed up the rusty mess that came out, then I started in the coolant holes with a small torch and a screwdriver. Just scraping that around in all directions in each hole produced the extra pile of rust and stuff pictured. Most of it was on the bottom of the waterway at the rear cylinders, but quite a lot had bridged between cylinders or between a cylinder and the block. That all acts as an insulator that keeps the heat in and slows down the flow.

 

I don't know how the car was treated for the last 25years, but at least I'm sure it will be better in the future!

jesus! looks like the previous owner didnt know what coolant was :dance:

2 words - HOT DIP.

 

Man the time spent doing that you could have paid 40 bucks for a hot dip at your local engine builders! All sorted!

surely when you get a head skimmed they pressure test it to make sure its usable, and also hot dip it? i know my head came back as clean as a whistle :dance:

Usually, yeah, but that's hix block not his head.

ah, miss read :D

 

either way, i think id rather strip block and send that and head in to get cleaned properly.