Simon,
I've used the Clik-Adjust with success for years now; with a little
practice, it's a great tool.
Firstly, in my opinion, you can't use the thread count of the adjusting
nut to set the valve clearance. Why? Because the gap is set at the top
of the valve stem, while the adjusting nut is on the opposite side of
the rocker shaft. This would be fine if the two (valve stem and
adjusting nut) were equidistant from the centreline of the shaft, but
they are not; the adjusting nut is closer. So, if you move the adjusting
nut 0.012", the gap at the valve stem will be larger than that.
Conversely, to get the proper 0.012" clearance, you would have to move
the adjusting nut _less than_ 0.012".
To calculate:
The parts manual specifies the locking nut (for the 6-cyl) as FNN 206,
which, according to Anderson/Moment p. 186, is a 3/8" shank diameter UNF
thread, which has 24 threads per inch. The locking nut and adjusting nut
are on the same shaft, so the adjusting nut also has 24tpi.
The Clik-Adjust clicks every 1/30 of a revolution (30 clicks per
revolution, or 30 clicks per thread), so to move the adjusting nut
0.012", you would need:
24threads/inch x 30clicks/thread x 0.012inches = 8.64 clicks
However, using feeler gauges, I came up with 7 clicks to set the gap at
0.012", less than the 8.64 clicks calculated. So, I use 7 clicks.
Here is my procedure:
Set valve clearance to .012! (cold) using Gunson Clik-Adjust.
Use 47 clicks! to get proper gap.
On each valve:
1) Loosen locking nut with 9/16" crescent wrench;
2) Finger tighten adjusting screw, ensuring locking nut is still loose;
3) Finger tighten locking nut;
4) Seat Clik-Adjust tool onto adjusting screw and locking nut assembly;
5) Turn Clik-Adjust screw driver back and forth to make sure Clik-Adjust
screw driver is engaged and turning adjusting screw;
6) Tighten Clik-Adjust screw driver until loud click is heard;
7) Back off Clik-Adjust screw driver 7 clicks;
8) Tighten locking nut while keeping Clik-Adjust screw driver as still
as possible."
Hope this helps,
John P. New
London, Ontario, Canada
'67 BJ8
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-----------------------------------------
On Sun, 2006-07-02 at 21:43 +0100, Simon Lachlan wrote:
> I have just bought a Clickadjust tappet thingie on eBay. It seems like a
> useful piece of kit though I wonder if it will prove to be indispensable.
> Anyhow, Im a sucker for useful gadgets and it was cheap enough so.
> Per the instructions, to use CLIKADJUST the user needs to identify the type
> of thread used on the tappet adjusting screw. To do this, one screw (Ball
> Pin) should be removed, and the pitch of the thread measured (see figure
> below), or the number of threads-per-inch (T.P.I.) measured. The charts
> can then be used directly. Anybody been there and done that and got the
> info?
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