EGT probe installation

[Steve Von Gruben]

Hello, all, I am getting ready to install EGT probes on all the cylinders on my Twin Comanche. There is a limited space available in the exhaust stack area and I am looking for advice on "best way" to do this.

Steve

[Steve Von Gruben]

Would anyone like to share a picture of their installation?

Steve

[jeffrey aryan]

Steve,

FYI,

EGT probes are exhaust gas temperature probes that are usually installed on the exhaust pipes or system. The way I would start is, make a preliminary mark with a grease pencil, sharpie or pencil on your exhaust pipes with your lower cowlings on. This is to see your clearance between the cowlings, spark plugs and wires. Then take a 30 minute break. Come back to see if your marks will clear everything and show no interference of the above mentioned items and anything else. Then go ahead and remove the lower cowlings and begin the installation process. Remember marks can be erased but drilled holes need to be repaired. I'm no mechanic but that is how I would start. FWIW

Jeff Aryan

[Charles Schefer]

I would NOT mark with pencil. Use the grease pencil or sharpie. Many A&Ps have warned me that pencil marks promote corrosion that will lead to premature pipe failure. The exhaust shop I used (Aerospace Welding - http://awi-ami.com/ confirmed this and said NEVER mark an exhaust pipe with a pencil.

Now... interestingly they all referred to "pencil lead" and I I can see how lead and stainless steel might set up a galvanic reaction of some type and I asked about that and commented that pencil "lead" is now really graphite so does it really matter? The exhaust shop and A&P/IAs I spoke too couldn't remark on that point but once again emphasized that the pipes should never be marked with a pencil and so I have refrained from doing so. We used a sharpie.

Just my 2-cents.

- Charles