34 heater shut off valve

Posted by Terry Cantelo On 2010/7/27 2:16:20

Hi Guys,
We have had an unusual run of hot weather here in the U.K. and I have been a bit cautious when taking the old girl out after my spell of overheating, but she has performed very well and has not reached any critical temperatures thus far, so there has indeed been an improvement.
Last sunday it must have been in the 80's and becoming rather warm in the cab even with all the vents open and my wife complained that her feet were boiling. On checking I found the heater was throwing out tons of heat and I decided to shut off the valve on the rear of the cylinder head. This promptly stopped the heat in the cab but I noticed that the temperature gauge had also stopped working. On turning the valve on again the gauge started to function once more. But of course the heat was back.
The question is :- Is the valve the feed to the gauge or is this suggesting a blockage in the waterways in the head at the take off point for the water temp. gauge?
I am assuming that there are waterways in the head not being that familiar with this type of engine. If so any easy fix cures please.
Thanks in anticipation
Terry