Last time we spoke with our hapless hero he was licking the wounds inflicted
by the evil TR6, which refused to idle properly, and which continued to give
him problems despite large sums of cash and time being lavished upon it.
So Saturday night I'm at my old man's house....having a beer with the person
responsible for this macabre fascination with things British. As an owner of
two Jaguars (52 XK120 FHC, and 67 420 sedan) and retired airline mechanic he's
got some mechanical mantra built up. So we're discussing the symptoms over
beers,
and he's shaking his head and laughing with me.....and I"m going over things
step
by step when I am struck by inspiration. It was one of those moments that
people
who work for weeks or months on math problems must know well.
I figured out that the vacuum retard portion of the distributor was screwed in
to
tightly, thereby putting undo tension on the advance plate, thereby retarding
the
spark too far, and furthermore, not allowing the vacuum ADVANCE to work
properly.
See....when I disconnected the vacuum retard line there was no "500 RPM
increase"
as there should be.
Ecstatic I lept from my chair and told dad I was going home (by MGB of course!)
to
fix the TR. "I think I figured it out", I said! Ever the pesimist he said, "I
doubt it..."
Raced home and lifted the bonnet, pulled the vacuum retard line and unscrewed
the
retard unit a few turns. Started the car and it settled in to a very nice
burbling
idle. Boy was I happy. I unscrewed it some more....things got better. A nice,
even idle. I'll be she's even running richer. Need to check that.
Now, here is the lesson, it seems very important to me.....
If your vacuum retard is not in its "standard" position (I don't know if there
is
an index for this sort of thing or not...there is no discernible "detent" to the
thing) then setting the spark static (set car to #1 cyl 12 BTDC and turn
distributor
till points break) will not be the right setting. As an aside...there was a
band
around the vacuum unit, I wonder if it was to prevent the thing from being
rotated
or not. Would seem not as there is an A and a R with arrows indicating which
way
to rotate the thing in order to advance or rotate it, stamped ON the
distributor body.
The Bentley manual calls for 4 degrees AFTER TDC for the car at idle (one would
presume
this is with the vacuum retard line CONNECTED as that is pretty far retarded)
and I
set it for that. The car is much happier now. And so am I.
It's not perfect yet....but it's much better....and might even make it through
smog.
On another note, it is interesting, but even with the hi-compression head, even
on the
lousy gas that we get these days, and here in CA, the car will not ping under
heavy
load. In fourth gear at 1200 RPM step on the pedal and it just goes! I guess
the
Triumph engineers knew what they were doing heh? Or am I still too far
retarded? I
suspect that's the vacuum retard helping things out? Or does it only work at
idle?
So many questions, so many questions.
Regards,
a happier,
teej
--
TJ Noto Palo Alto CA USA
http://www.rahul.net/tjn
Owned by: 95 Ducati 900ss 65 MGB 87 BMW 325is 70 Triumph TR6
"Once again Yankee ingenuity Triumphs over British craftsmenship"
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