[TR] A Type OD

[Randall]

> Next, the OD would work for about 20 minutes, then drop out.  A few times
> I could actually feel it chatter as it rapidly kicked in and out before
> dropping out altogether.  That made me think it was likely electrical.  I
> swapped out the solenoid, relay and the OD switch.  No improvement as
> intermittency remained.

Connect an (incandescent) test light from the output of the relay to ground.
If you can see the light dim or flash when the OD acts up, you know the
problem is electrical (and with the relay or the circuits leading to it).

If the light remains steady, then the problem has to be farther downstream.
Could still be electrical (solenoid or the wire to it), but possibly also
hydraulic/mechanical.

> But here's the thing:  when I've tested with all the circuits connected--
> that is, the relay and switch, the snap isn't pronounced, but the solenoid
> does kick in as it should.

That does seem suspicious.  Having pressure in the OD does muffle it
somewhat, though.

> I did this per the book, using the 3/16 drill bit, which assumes that
> operating oil pressure is sufficient then.

It also assumes there is no wear in the cam & spindle, which is not always
the case.  See the Buckeye Triumphs articles for an alternate method of
checking how far the valve ball actually moves.  FWIW, I believe the motion
of the ball should be a minimum of 1/32" (.030").  I doubt that adjustment
is your problem, but it's a good check to make at least once, IMO.  Once
you've established that the cam & spindle are not worn, you can go back to
using the 2/16" rod.

> 2) When I test the OD on blocks, do I need to increase engine speed beyond
> idle to get a proper test.

It may take slightly longer to build pressure in the first place, but the OD
should work normally once the pressure comes up.

> 3) If the thing still tests sketchy, where can I get an oil pressure gauge
> that will screw into the operating valve so I can really know what's going
> on?

I believe Jay Holekamp still sells them http://www.geocities.ws/jholekamp/

Or it's not too hard to build your own, starting with a replacement plug
(506117 @ TRF).  Drill the end, braze a length of tubing into it, make a
(liquid filled) pressure gauge to the tube.

> 4) Do I remember correctly that after turning off the OD with the car
> stationary, it takes longer than when it's actually on the road?

Should be pretty much the same.  Maybe just slightly longer because the oil
will be cool and thicker; which in turn depends on what oil you are using.

-- Randall