CHT & EGT replacement sending units

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DoubleOught
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CHT & EGT replacement sending units

Post by DoubleOught »

I'm trying to restore the EGT & CHT the wiring coming out of the back of both receiving units are black & white. A/C Spruce only list sending units with red/yellow or yellow/brown. Any advise or help greatly appreciated. OOW
There are old pilots & There are bold pilots, But there are no old bold pilots !!!
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1953 Cessna 170-B N3401C
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Bruce Fenstermacher
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Re: CHT & EGT replacement sending units

Post by Bruce Fenstermacher »

My advice is to get the leads that match your gauges. These are calibrated leads. Just any, regardless of color, won't work.
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DoubleOught
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Re: CHT & EGT replacement sending units

Post by DoubleOught »

That's what I was trying to figure out the gauges have no brand name of numbers on them , so I was going by what A/C Spruce has in their catalog , and it's called out in color of leads.
There are old pilots & There are bold pilots, But there are no old bold pilots !!!
2010 Team Tandem Airbike N700XX
1953 Cessna 170-B N3401C
First plane Cessna 175A N7000E
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edbooth
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Re: CHT & EGT replacement sending units

Post by edbooth »

Typically most thermocouples used are type "J" iron/constantan with red/white leads (red being -) and type "K" chromel/alumel with yellow/red leads (red being -) . There are temp indicators out there that do not have this same color coding on the indicator inputs and you need that particular instruments instruction sheet or schematic to determine which thermocouple goes where. The type "J" are normally for lower temps, CHT and the type "K" for EGT.
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170C
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Re: CHT & EGT replacement sending units

Post by 170C »

I took the lazy man approach :roll: My EGT & CYL temp gauges are tough to get to as my radios are below them so access is a bugger. My CYL temp still works while my EGT doesn't. I don't lean by EGT anyway (I lean with my digital tach). I put a label on the EGT as being inoperative. Now when my CYL temp dies, I will have to fix both I suppose.
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blueldr
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Re: CHT & EGT replacement sending units

Post by blueldr »

Frank,
I must admit that CHT and EgT are nice to have, but only "Oil Temp." is required.
BL
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mongo2
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Re: CHT & EGT replacement sending units

Post by mongo2 »

If it helps any, I have a Westach 2DA1 Combo CHT\EGT, with new thermocouples that both have black and white leads. When I return home later, I can tell you what pin numbers they are each on. Not sure of your gauge though.

mongo2
Rick Champagne
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mongo2
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Re: CHT & EGT replacement sending units

Post by mongo2 »

Ok,I checked the gauge,and on the Westach\Westberg 2DA1, CHT white is to pin 1, black is to pin 8, For the EGT, white is pin 4, and black is pin 5..
I believe the senders were from Spruce, and maybe type J.

RC
Rick Champagne
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DoubleOught
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Re: CHT & EGT replacement sending units

Post by DoubleOught »

10/4 on nice to have, I have the receiving units in my panel , if I can make them work I don't have to remove them. Thanks for all the information. OOW
There are old pilots & There are bold pilots, But there are no old bold pilots !!!
2010 Team Tandem Airbike N700XX
1953 Cessna 170-B N3401C
First plane Cessna 175A N7000E
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