Engine monitors

[md11flyer]

[N3322G]

[Jay]

[N3322G]

[Ben Ayalon]

[commanchepilot]

I'd be interested to know everyone's thoughts on where the probe should be.. I have the tanis system already in the cylinders. Since reading cylinder temperatures would be a relative temp anyway, would it really matter if the sensors were under the spark plugs?

[Ben Ayalon]

I don't know the Tanis but CHT is not relative reading, it is actual reading and what you want is actual. If the sensors are under the spark plugs your reading is ~25F lower then true. Only the EGT are relative readings.

Ben

[Chuck Lee]

I have an Insight GEM 602 and a Tanis system. I bought the GEM unit when they first came out over twenty years ago. I have had to change a few EGT probes over the years, other wise it has worked well. The other engine instruments I have are from E.I. (volt/amp, oil temp/pres, fuel flow) and they all great. I like that the instruments are independent of each other so that if a problem does occur I am not totally out of business.

Chuck Lee

[Chuck Lee]

Bill;

I could not remember the exact numbers on the difference of the under the spark plug vs in the cylinder probes last night at the office. I kept a copy of "Light Plane Maintenance" the February 2006 issue that gave a "primer" on engine monitors. They say the "spark plug thermocouples consistently tend to read 50 to 75 degrees higher than their cylinder head-well counterparts."

If you would like a copy I would be happy to email it to you.

What ever system you use they are well worth it.

Chuck Lee

[Chris Kuyoth]

[Andreas Riedel]