pmolitor Posted November 22, 2013 Share Posted November 22, 2013 who makes good pyro gauges? my factory mack gauge is reading hotter than it really is. Ive seen lots of gauges from $80 up to $300. just want a good reliable gauge. Quote Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/ Share on other sites More sharing options...
rsb502 Posted November 22, 2013 Share Posted November 22, 2013 Why not just get a new Mack thermocouple and or gauge, I've replaced thermocouples on most of the trucks I've had and never actually had a bad gauge. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-217940 Share on other sites More sharing options...
farmer52 Posted November 22, 2013 Share Posted November 22, 2013 Just like a fuel gauge, typically the sender is the issue. I also suggest replacing the thermocouple (TC). The TC for my EM7 was about $65 and easy to replace. There should be a plug-in connector near the TC. Quote Ken PRR Country and Charter member of the "Mack Pack" Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-217966 Share on other sites More sharing options...
rsb502 Posted November 22, 2013 Share Posted November 22, 2013 The older thermocouples like on my RW's have two ring terminals that you screw together. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218013 Share on other sites More sharing options...
e9500v8 Posted November 23, 2013 Share Posted November 23, 2013 Hewitt industries make the best pyro !! I love there 3" radial gauge ! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218035 Share on other sites More sharing options...
pmolitor Posted November 23, 2013 Author Share Posted November 23, 2013 my thermocoupler is new. wiring is bad. maybe gauge? don't know how to isolate and diagnose. Quote Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218036 Share on other sites More sharing options...
farmer52 Posted November 23, 2013 Share Posted November 23, 2013 my thermocoupler is new. wiring is bad. maybe gauge? don't know how to isolate and diagnose.Likely one of the wires is broken. That was the problem with mine (after I broke the TC trying to remove it and replace with a new TC). Use a continuity light to check your wires. Mine are solid core and one was broken at a sharp bend near the engine. Quote Ken PRR Country and Charter member of the "Mack Pack" Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218056 Share on other sites More sharing options...
rsb502 Posted November 24, 2013 Share Posted November 24, 2013 Yeah thermocouple s measure resistance and the wire leads are part of the equation, you can't cut em or shorten them up it throws it off. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218182 Share on other sites More sharing options...
pmolitor Posted November 24, 2013 Author Share Posted November 24, 2013 how do you determine the length of the wires? I did trim them to hook up the new thermocoupler. they were in pretty bad shape so I took a 8 inches out. Quote Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218194 Share on other sites More sharing options...
Dirtymilkman Posted November 25, 2013 Share Posted November 25, 2013 You can cut your thermocouple shorter. It changes nothing. Resistance has nothing to do with it. Quote Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218293 Share on other sites More sharing options...
rsb502 Posted November 27, 2013 Share Posted November 27, 2013 ok Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218596 Share on other sites More sharing options...
pmolitor Posted November 27, 2013 Author Share Posted November 27, 2013 just did a search on calibration of pyros. found a interesting read on another forum. (don't know how to post a link) interesting as in I don't understand a word of it. seems you can calibrate with changing the leads from the gauge to the tc. I have to reread to understand it. Quote Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218620 Share on other sites More sharing options...
pmolitor Posted November 27, 2013 Author Share Posted November 27, 2013 basically, my wires are to short and don't have enough resistance and it means my gauge is reading way high. so I need to find out how long the wire need to be to provide the correct readings. Quote Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218626 Share on other sites More sharing options...
rsb502 Posted November 27, 2013 Share Posted November 27, 2013 Hmmm, well I'll be damned. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218627 Share on other sites More sharing options...
Dirtymilkman Posted November 27, 2013 Share Posted November 27, 2013 From "The Sensor Connection" a place that deals with thermocouples and sensors. Question:Can I shorten the EGT probe's cable or will that mess up the accuracy because the ohms of the wire won't be the same? Reducing the length of the EGT probe's wire by a few feet typically will not affect the operation or accuracy of the probe. Quote Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218650 Share on other sites More sharing options...
pmolitor Posted November 27, 2013 Author Share Posted November 27, 2013 found a better page. it depends on manufacturer on whether you can shorten the wires. only one would allow slight adjustments. I'll do some more reading over Turkey day and report back. Quote Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218669 Share on other sites More sharing options...
rsb502 Posted November 27, 2013 Share Posted November 27, 2013 Im going on what I was told by the guys at Mack about a Mack thermocouple, I just bundle up the spare wire and zip tie it there under the hood. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218723 Share on other sites More sharing options...
fullfuel01 Posted November 27, 2013 Share Posted November 27, 2013 You cant cut pyro wire. That will lead you to a bad reading. There is no positive or ground on the gauge because the probe makes is own current with the heat.I think about one volt. If you cut the wire you change the resistance and modify the reading! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218739 Share on other sites More sharing options...
pmolitor Posted November 28, 2013 Author Share Posted November 28, 2013 do you know the lenght of the wire for the mack gauge? that would be the cheapest part to experiment with. Quote Link to comment https://www.bigmacktrucks.com/topic/33602-pyro/#findComment-218777 Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.