[Healeys] Block porosity

[Ian Hey]

When I rebuilt an engine which had been standing without water for forty
years, there was a huge amount of brown dust (rust) in the waterways.  I
therefore removed the core (freeze) plugs and all brass components (main oil
gallery plugs) and had the block dipped in I know not what, but it came back
looking like new.  Removed brass components since the fluid used destroys
brass.  It also destroys shell bearings, so new cam bearings required.

 

I knew about the Healey porosity problem but did not know if my block
suffered, so I had it vacuum impregnated with resin.  This process gets
resin into all surface defects, and eighteen months later when I had to
change a core plug, the inside of the block waterways were still like new -
no corrosion at all.  I believe that this was the best thing I did to my
block.

 

The vacuum impregnation process puts the clean block into a chamber which is
evacuated.  Resin is then allowed to enter, and is then drained out.  The
block is then placed in a 90 degree centigrade (194 F) water bath, which
cures the resin (resin cure temperature 60 degrees centigrade (140 F))  This
process was done twice, just to make sure.  This is a standard process for
castings in the UK to cure casting porosity or other defects such as
corrosion.

 

A possible alternative to a replacement block?

 

Ian Hey

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