Engine/Transmission (1998.5 - 2002) EGT thermocouple test procedure?

[Gary - K7GLD]

In another thread, a question was raised concerning the lower than expected EGT temps many of us are seeing when in high-demand situations such as towing in the hills, and especially when using power enhancements such as the Edge Comp.



There was an article in TDR #34 outlining a test procedure for testing - I think a standard propane torch was involved - but I can't find my #34 to verify the test procedure - can anyone help with the procedure and the temperature the test SHOULD display?



It might also be helpful to hear how many other owners with EGT guages in frequent heavy pulling situations and power boxes like the Comp are normally seeing temps of 1300 degrees or less, pre-turbo...

 

[jlccc]

My #34 is at the office, but Robin at TDR will xerox that one article and fax it to you if you ask nicely...



Or, if you want to send me a PM I'll call you Monday and we can discuss.

 

[Gary - K7GLD]

Thanks - lets wait a bit and see if anyone pipes up with the info here - all I really need is something like:



"remove the thermocouple from the manifold, and while still connected to the guage, hold it up to the tip of the torch set at medium flame - guage reading should be approximately 1400 degrees... "



Wish my memory (and storage habits!)was better - I remember glancing thru the article, but have now misplaced that issue AND my memory...

 

[Cummins Cowboy]

gary, i just pulled out my mag and read the article basically to test you need to pull the probe put a propane torch so that the probe is in the center of the flame. It should reach a temp of 1700 degrees in 35-50 seconds.

 

[Gary - K7GLD]

THANK YA KINDLY!



I'll give it a whirl later today, and post results...

 

[Gary - K7GLD]

HOOoooKAaaay... .



Test done - results in:



With thermocouple in the torch flame, within 30 seconds, guage temp climbed rapidly, smoothly and steadily up to its max of 1500 degrees, at which point, I had my wife pull it outta the flame...



That should lay to rest any concerns - mine or other folks - as to the reliability of my operational EGT readings, I appreciate the concern and help of all who contributed...

 

[Roger Ledbetter]

So how about accuracy?

I have often wondered about the accuracy, if you only got 1500 degree and it should go up to 1700 does that mean it is off by 200? I replaced my probe once thinking it was off, the new one gave the same reading though. Have not tried the torch test yet.



BTW Gary, look for me on 40 meters, would love to work CTD to CTD mobile

'73 Roger K7EZ

 

[Gary - K7GLD]

READ it again roger - I said I *stopped* at 1500 degrees, cuz that's as high as my guage goes - no need or reason to go any higher...



The temp was still rising, but no purpose to heat the T'couple higher than I could monitor...

 

[Roger Ledbetter]

Sorry Gary

I mis understood. I did not get the *stopped* part on your post.

My gauge ends at 1500 also. Guess the only way to test how accurate the probe would to be measure its voltage with a millivolt meter. Then put a known voltage vs temp and check the meter part of the circuit.

What kind of antenna do you run on HF? I use a Atas 100 on a home brew mount where the third brakelight used to be most of the time but have a DK screwdriver on bumper for serious work.

'73 ROGER K7EZ

 

[Gary - K7GLD]

Seeing how my probe and guage reacted, I pretty confident all is well - without an accurate test standard of some sort, you can't really be 100% accurate, but I'm convinced my own test puts me safely inside the ballpark...



On my mobile in the new truck, I'm using a homebrew 40 meter monobander - and have a 20 meter Hamstick on an identical mount on the other side of my tool/fuel box. I've found that I can run my coax to a "T" connector on the first antenna, then continue the coax over to the second antenna - and lo and behold, instant bandswitching between them with NO apparent loss of efficiency or SWR on EITHER band!



I hope to have my 600 watt Ameritron amp installed soon, then I can make a little more noise from the mobile than I can now with the 100 watt Icom 706... I'm retired - and 40 meters is usually good for me into S. Cal - let me know what will work for you day and timewise, and maybe we can hook up...



Here's a pic of my install...



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