I will submit my experience with "bad sound" in our '60 BT7. At the Open Roads
meet at Lake Tahoe a couple years back and while on the event rallye, we
experienced a marked decrease in power while ascending the hill to Virginia
City. A ticking sound could be heard from the timing chain area, though only
at idle. In resignation & humiliation, we had to ride a tow truck back to the
Lake because the Healey could not climb the mountain. After returning home, I
decided to pull the engine and found on teardown that the crankshaft timing
gear had "worked" itself on the crank snout to the point where it was no
longer tight, causing extreme wear on the woodruff keys, the gear & crank key
slots. I estimate another 25 to 50 miles would have sheared the key
completely. This movement caused wide variances in timing of valves & ignition
with subsequent losses in power.
In this case it necessitated a weld & resizing of the crank snout & keyways,
new gears & etc., to put it back to normal. Of course I just kept going and
renewed the entire engine. Just got it running a couple weeks ago following
the rebuild and rewire of the car in "spare" time.
Rich Young
1960 BT7
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