EDM-830 and oil temp

[pbarge]

Hello gurus,

 

I am new to the forum and this is my first post.  I recently acquired a 1966 M20E and have really been enjoying its speed and efficiency.   I recently had an EDM-830 installed and there is a small glitch.  The 830's oil temp will climb up to 260 degrees by the time I reach cruise altitude.  The factory gauge indicates around 190.  The cylinder head temps range from a low of 285 to 323 degrees.  Finally, the oil looks normal and is not black, thin, or have any burnt odor (I use AeroShell 15-50).  JPI says there sill be some difference between the factory and 830 temp but not 70 degrees.  We have tried different sending units, and tested the 830 with a thermostatically controlled water heater up to 200 degrees and it has been spot on.  The factory guage is a little off, but I still don't see how the oil temp could be as high as the EDM indicates due to the other readings.  Has anyone seen this before?

 

Thanks in advance!

Pat

[carusoam]

Pat,

Welcome aboard!

i assume that you have two different sensors, the JPI and the ship's gauge.  It would be interesting to know where the JPI is actually reading the high temperature.

See if you can share a couple of photos of the sensor locations...

Keep in mind, I am a PP, not a mechanic.

Best regards,

-a-

[TWinter]

That seems high on the JPI. On my E the temps would creep around 210 +/- in hot TN summer at lower altitudes just cruising around, but never saw 260. When you try to cool by cracking cowl flaps open do you see a substantial drop on the JPI (when I say substantial I mean 15-20) ?

 

-Tom

[ArtVandelay]

Does the oil temperature read ambient temperature when engine is cold?

[Guest]

The usual location for a JPI temp probe is in the front right oil gallery with very little difference in temperature.

Clarence

[N601RX]

Check to make sure the engine monitor is grounded directly to the engine and not behind the panel.  If the oil temp is really 260 there will be a very noticeable drop in oil pressure. 

[ArtVandelay]

Check to make sure the engine monitor is grounded directly to the engine and not behind the panel.  If the oil temp is really 260 there will be a very noticeable drop in oil pressure. 

Wouldn't a ground problem be seen in other erroneous sensor indications?

[pbarge]

Thanks for all the replies!

JPI has the oil galleys in the front of the engine as the place for the sensor and that's where mine is.  The EDM does read ambient temperature when turned on and as I said it is spot on when testing with a water heater.  The oil pressure has been in the 65-70 psi range.  I will talk to the mechanic about grounding.  I called Don Maxwell in Longview, TX (I used to be his internet provider) and he suggested moving the EDM probe to the factory oil temp position and see what it reads from there.  He also suggested an inspection of the vernatherm to make sure that it is functioning properly.  Any other ideas from you guys is much appreciated!

[cnoe]

Just another data point here: my JPI 830's oil temp probe is installed in the forward right galley port too and tracks very closely to the primary gauge. In the latest Savvy Analysis Report for my J covering 35 flights the average cruise oil temp was right at 200 degrees in this hot south-Texas summer climate with a max of 213 F. Keep us informed how it all works out. There may be something to be learned here for us all.



Sent from my iPad using Tapatalk

[pbarge]

Hey will do and thanks for the info on your bird!

[pbarge]

Well the mystery has been solved!  Turns out that the EDM was telling the truth.  As suggested by Don Maxwell the mechanics checked the Vernatherm and it was not functioning at all!  I'm darn glad that I bought that EDM for I would have never known there was a heat problem as the factory guage is obviously bad.  I just hope that this has not been going on for very long.

[cnoe]

Glad to hear you caught it before bigger problems emerged!

 

[carusoam]

There may be some reading you can do regarding vernatherm and oil cooler maintenance.

These items come up every forty or so years.

How to remove and test, and how to flush the oil radiator.

put some key words in the search function, see what shows up...

Best regards,

-a-

[pbarge]

Hey a good idea and will do....

[Guest]

Check Lycoming SB 518D.

Clarence