These spark plug testers are suppose to be
able to check the spark under pressure
as was one function of these early cleaner/
testers.
However – tester # 1 spark isn’t being
generated buy a spark plug.
Tester #2 can test a spark plug however
I don’t believe either could generate
enough pressure to be of any real use.
I have a collection of devices to check
spark. Some manufactured, others home
made. I use # 1 a lot as (after some
modification) the clips make it easy to
use, I can adjust the gap by turning the
studs the wires are attached to, and
the spark is relatively visible compared
to other testers I have tried. The pump
and gauge have no value other than
something to hold on to in IMO.
Tubs
A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.