Chapter 7 Concrete Thinking

  With oiling issues partially addressed, I turn my attentions to the block's water jacket.  Studebaker blocks were cast in Studebaker's foundry located at their base of operations in South Bend, Indiana.  Anyone who has peered into the water jackets can attest to the wide variety of foreign objects that occupy that space.  Casting sand, wire used to reinforce and position cores, dirt, rust, a little bit of anything and everything.  This block was no different.

  The hot tanking at Precision Engines II had done a pretty good job of rinsing most of the water jacket clean, but there was still a fair amount of rust and corrosion.  One bank at a time, I filled the water passages with muriatic acid.  If you do this, be prepared for some pretty nasty fumes which will rust any ferrous metals in the vacinity.  After allowing 10 minutes or so of foaming and bubbling, I rinsed the block with fresh water.  Then repeat on side 2.

  The sonic wall testing had shown a few thin spots down low in the cylinders.  This wouldn't be exposed to combustion pressures as the piston rings were well above that point, but any flex would be potential problems for the rocking of the piston at bottom dead center.

 

  Moroso and several other companies offer a block filler which is close to the expansion properties of cast iron.  I just wanted to reinforce the block at the bottom which is called a partial fill.  I positioned the block level front to back and rotated so that the self leveling filler would be over the main oil galley tapering out to the bottom of the core plugs.  Mixing enough filler for one side, it was simple to pour the mixture through a funnel into several of the block deck water ports.  After tamping and helping the mix level with a long paint mix stick, it was topped off to fill up to the desired point.  The next day was a repeat of the process on side two.

  I need to go back a little and pick up a modification made before the block was filled.  In my trips to Bonneville and reading the adventures of other Studebaker guys I noticed several runs had to be aborted due to core plugs coming out and dumping the block coolant during runs.  Definately not what you want when you're backing up a record run and something like this forces you to shut down.  Explanations abound but center on block distortion loosening the plug in its seat and coolant pressure doing the rest. 

  Pretty simple fix really.  Stealing one of Jeff's ideas he stole from someone else, I'd just thread the block to accept iron pipe plugs.  This takes some cleaning up of the existing casting core opening.  BTW, core plugs, or what some call freeze plugs are not to keep your block from cracking when the coolant inside freezes.  Core plugs exist as an artifact of the casting process.  Foundries have to have a way to get the sand out of the block after the casting and cooling process.  Back to the story.  The major thing to remember when threading for a threaded core plug.  That tap is going to get very close to the water side of the cylinder wall.  Forcing the tap to the point it contacts the cylinder wall and pushes on it may result in cracking the cylinder.

  On to the next project in block prep...