> I've just rebuilt a Daimler 2.5 V8 - iron block, ally heads - and the
> passages had to be welded up they were so bad. The Daimler expert who did
> it, (Russ Carpenter, if any of you remember drag racing in the '60s) said
> it was imperative when refitting the heads to use Hylomar jointing
> compound around the water passage ports.
I rebuilt a 2.5 Dart engine for a client about 15 years ago and it's still
probably my most enjoyable engine rebuild. Lovely castings, hollow crank
pins with sludge traps and a beautiful elegant design.
The heads corrode badly because they have a very high magnesium content in
the aluminium and this one was no exception. However it was a simple job to
mill out the corrosion, get it TIG welded with an appropriate grade of wire
and then remachine the waterways back to their original shape. I also
blueprinted and balanced the whole engine including equalising the deck
heights of the block on both sides relative to the crank centreline. It was
way out as standard with some slope from front to back on both sides and one
side a lot higher than the other. I made a special jig to swing it on the
mill through 90 degrees about the main journal housings which took longer
than the actual machining but I felt it was worth the effort. If I recall
correctly the CR was about half a point higher on one side as stock which is
a big difference.
The scary bit was repacking the crank rope seal as I'd never done one
before, or since for that matter, but apparently it didn't leak a drop once
back in the car so phew!
--
Dave Baker