I found the problem with the #4 CHT display on the Grand Rapids EIS: Had 2 
loose wires for the same thermocouple.  The wire connection terminal block 
is a European style barrier strip and is forward of the instrument panel and 
under the forward deck where it is dark and scary and the main spar really, 
really resents your head and shoulders even being there.  Fear not, gentle 
souls, I removed a few screws with my trusty cordless screw driver to open 
the inspection panel on the forward deck.  This panel provides wide open 
access from the firewall to the instrument panel and from one fuselage side 
to the other.  I re-attached the 2 wires and all is well.
The reason for the European style barrier strip is: I could not keep the 
crimp pins for the Sub-D connector attached to the Iron and Constantan wires 
on the thermocouples.  These wires are too hard for the brass pins.  The 
European style strips have screw clamping action and a Nylon grip on the 
screw similar to stop nuts.  I got the smallest strips that Radio Shack had, 
but the wires were too small.  So, you have to be very careful to get the 
wire directly under the screw.  From the barrier strip I ran copper wire to 
the Sub-D connector.
In retrospect I could have stripped the thermocouple wires longer and 
doubled the end back on each wire to double the size for better clamping.
We can also discuss extending thermocouple wires, but that will be another 
topic.

Put another 0.3 hours on the Hobbs practicing taxi and warming up the VW to 
check CHT readings.

Sid Wood
Tri-gear KR-2 N6242
Mechanicsville, MD, USA

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Keep  posting. I Am folowing  your story.
Stef




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