I've had my CHT in both locations. I prefer locating it under the #3 cylinder head nut sandwiched between a couple of washers. It is too prone to break if placed under the #3 spark plug as it was intended. I didn't notice a very large error in the temperature reading when located on top of the stud washer. You shouldn't have to re torque all of the head bolts. I changed my thermocouple location on a cold engine. You should use only one new or a freshly annealed copper spark plug washer for that #3 plug.
-Joe Scappoose Ore. > I have heard several pros and cons about where to place cylinder head > temperature (CHT) probes. One placement is at the sparkplug gasket > (substituting for the sparkplug washer?). The other location > is under a > head bolt (exact head bolt varies). The sparkplug location would tend > to have higher temperature readings than under a head bolt. > Then there > is the wear and tear from checking and changing sparkplugs. Does the > sparkplug washer provide a better seal than the thermocouple > washer? Is > there any concern for how far the sparkplug goes into the > cylinder using > different washers? If I put the CHT probes under head bolts, > would the > entire set of head bolts need to be re-torqued or just the > one bolt with > the probe? > Does it matter which brand of engine for the above considerations? > > Sid Wood > Tri-gear KR-2 N6242 > Mechanicsville, MD, USA > sidney.w...@l-3com.com > > > Mark Langford wrote... > ... I'd had the sparkplugs out and when I put them back in one of the > CHT probes (which I noticed wasn't looking that good) got a little > twisted and frayed. That allowed one of the sparkplug thermocouple > probe wires to short, which makes the EIS a little crazy... > >
