Well, just hooking the meter to the receiver doesn't tell the whole story.
If you can hook the volt meter to the coax, both at the receiver and at the LNB WHILE the LNB is connected, then you have even more to go on.
Possible problems include bad connectors anywhere along the path
Bad coax
LNB pulling too much power
flakey voltage regulator in the receiver
etc.
So for instance, if the coax has a lot of voltage drop (either due to physical damage or bad connectors), you might find 13/18 volts at the receiver end, but a lot less at the LNB
But the test must be done with the LNB loading down the voltage on the cable.
Given enough data, we can point a finger at the failing component.
And besides, I thought you were a big Traxis-supporter.
What are you doing without one?

Can you borrow a receiver to duplicate the tests with?