pyrometer sender unit

[DanMac]

I've read about and talked to several people now that have installed pyrometers on their trucks and it seems to be the common thing to drill and tap the manfold ahead of the turbo for the sender unit. I've been a truck driver for some 27+ years now and have never seen this on a commercial truck and even asked some of our mechanics and was told (and shown) that the sender unit is always mounted in the exhaust just PAST the turbo. Is there a reason for the different location on a deuce I'm missing here? I did a quick search here and didn't really find any answers to this.

 

[gimpyrobb]

Most feel it would be better to know the temp going into the turbo so they don't melt the fins.

 

[rattlecan6104]

Most feel it would be better to know the temp going into the turbo so they don't melt the fins.

There is a couple "reasons" that I know of why people put the pyro probe after the turbo:

#1 The thought that a pyro probe will break and get sucked into the turbo causing catastrophic turbo failure.

#2 Laziness of not wanting to pull the turbo to prevent drill shavings getting into the turbo from installing the pyro probe.

I have talked to guys that race turbo charged vehicles, both gas and diesel, as well as diesel mechanics around here, all of which install the pyro before the turbo for exactly what gimpy said. Its just more accurate.

 

[gungearz]

I agree with you all... It does matter to people where they want theirs. There are ups and downs to either way you install a pyro meter but all in all, its better to have one if your going to be messing with the fuel outside factory settings then to not have one. When I do mine, I will put it after the turbo because my truck runs strong and healthy the way it is. 56mph @ 2600rpm's. If I wanted to go any faster. I wouldn't drive the deuce. I'm only doing the install to advance my engine monitoring. One day, I would like to fab up a dash plate and install fully digital gauges to get the most accurate reading at any moment I need it. Won't have to guess anymore... Good luck in which ever way you decide to install yours...

 

[rattlecan6104]

I agree with you all... It does matter to people where they want theirs. There are ups and downs to either way you install a pyro meter but all in all, its better to have one if your going to be messing with the fuel outside factory settings then to not have one. When I do mine, I will put it after the turbo because my truck runs strong and healthy the way it is. 56mph @ 2600rpm's. If I wanted to go any faster. I wouldn't drive the deuce. I'm only doing the install to advance my engine monitoring. One day, I would like to fab up a dash plate and install fully digital gauges to get the most accurate reading at any moment I need it. Won't have to guess anymore... Good luck in which ever way you decide to install yours...

Here is the web address for the digital pyro I used...
Digital EGT Gauge with TC-KEGT Probe [Combo-EGT] - $85.00 : auberins.com, Temperature control solutions for home and industry

 

[jwaller]

normally you will see 200-300 deg cooler temps when the probe is after the turbo. For the most accurate readings you will want it before the turbo.

You get the most accurate number so you can adjust your fueling so that you don't burn a valve, melt a piston, burn a headgasket, or turbine wheel in the turbocharger.

 

[donnerwetter58]

Here is the web address for the digital pyro I used...
Digital EGT Gauge with TC-KEGT Probe [Combo-EGT] - $85.00 : auberins.com, Temperature control solutions for home and industry

How has this EGT system worked for you? Any troubles or down sides to this set up? If it is a reliable system I need to get one of these.
Thanks for your help.

Dave

 

[Speddmon]

That's the same system I put in my deuce (although I think I had a different probe). Works good. Bright enough to see during the daylight and if you set the temp warnings correctly, the little blue warning light will get your attention if you are getting on it too much. You can also use an auxiliary relay and have it set off your air buzzer if you need more warning of a high temp condition than just the blue light will provide.

 

[donnerwetter58]

That's the same system I put in my deuce (although I think I had a different probe). Works good. Bright enough to see during the daylight and if you set the temp warnings correctly, the little blue warning light will get your attention if you are getting on it too much. You can also use an auxiliary relay and have it set off your air buzzer if you need more warning of a high temp condition than just the blue light will provide.

Thanks for the feedback. I have one of these on the way.

 

[m-35tom]

i had mine after the turbo, then installed it before the turbo. so in theory it should have read 200- 300 deg higher. it did not, it read almost exactly the same. i never could agree that this very hot exhaust gas, traveling as fast as it moves, could cool down that much in such a short distance.

 

[rattlecan6104]

How has this EGT system worked for you? Any troubles or down sides to this set up? If it is a reliable system I need to get one of these.
Thanks for your help.

Dave

I got this setup as well as their boost gauge setup... The pyro was a walk in the park, I was replacing my turbo and having the exhaust manifold mating surfaces machined at the time so installing pre turbo was a snap. if I remember for basic setup, only 3 wires and you are good to go. The boost setup however... that is a whole other can of worms... took about an hour to get the gauge setup to properly read and display boost levels, the two side by side look pretty cool though. I opted for the green readout, just wanted something a little different, insanely bright at night. I would have posted pictures for you, however I am having site difficulties in uploading pictures at the moment.

 

[DanMac]

i had mine after the turbo, then installed it before the turbo. so in theory it should have read 200- 300 deg higher. it did not, it read almost exactly the same. i never could agree that this very hot exhaust gas, traveling as fast as it moves, could cool down that much in such a short distance.

This is kind of what I have suspected. It seems to me that if the difference was noticable, the major diesel engine manufacturers would also place it before the turbo and not after like they all do. It's a comfort to hear it from someone who has tried it both ways though before I go ahead and install mine after the turbo as i had planned.

 

[PsycoBob]

From what I've read elsewhere, pre/post-turbo temp drops are cause by the turbo extracting useful energy from the exhaust stream. Diesels running 45psi of boost will show a lot more temperature drop than ours will.

Please remember that our turbos are more than enough to melt the innards of our high-compression engines, but they're not high performance by any sense of the term.

Mine hits 16psi @ 2500rpm & 1150 pre-turbo egts. I have a fully-shrouded aircraft-grade probe installed in the manifold from the rear (supposedly hotter) cylinders, just to give me worst-case numbers. The shroud slows down readings, but makes the probe a bit more robust.

 

[MidnightDuramax]

You can drill and tap the hole with everything fully assembled before the turbo. No need to take the turbo off. There are 2 ways to do it. 1 is to coat the drill bit and tap with a heavy grease to catch the shavings. 2 is to do the drilling and tapping with the engine running so the exhaust pressure will push the shavings out of the hole as you drill and tap.

 

[donnerwetter58]

You can drill and tap the hole with everything fully assembled before the turbo. No need to take the turbo off. There are 2 ways to do it. 1 is to coat the drill bit and tap with a heavy grease to catch the shavings. 2 is to do the drilling and tapping with the engine running so the exhaust pressure will push the shavings out of the hole as you drill and tap.

Those were the options I was looking at also. I ended up magnetizing the drill and tap. Worked very well. I just took my time and constantly removed the material attracted to the tools. I did both manifolds while I was there.

 

[maxspeed3]

Thanks for the link, I was looking for something like this for my deuce. My only question is on there webpage on the drop down menu for "selecting mounting type" which one should I pick? There are 8 choices... I know I'd have to drill and tap on the turbo, I just want to make sure I pick the "right" hardware.

Thanks!

Here is the web address for the digital pyro I used...
Digital EGT Gauge with TC-KEGT Probe [Combo-EGT] - $85.00 : auberins.com, Temperature control solutions for home and industry

 

[Tornadogt]

1/8 NPT is 1/8th tapered pipe thread.. would be the best in my opinion. That tap should be an just about any tap and die set if not they are cheep at the local auto parts store or NAPA...

Just ordered mine.. Thanks for info guys... I am going to tap and install a port both before and after my turbo just to be able to move the probe from one to the other under the same driving conditions to see what the difference is on my truck M931A2 Cummins 8.3 .. I will relay the information...

I'm not sure if it matters on a Pyro probe but with O2 Sensors it is best NOT TO install them in the lower part of a pipe (6 O-Clock Position) it may get moisture on it an give incorrect readings.. just a FYI...


Maxspeed3. I would not tap the turbo itself. Tap the exhaust manifold just before the turbo or the Exhaust pipe just after the turbo..

 

[maxspeed3]

1/8 NPT is 1/8th tapered pipe thread.. would be the best in my opinion. That tap should be an just about any tap and die set if not they are cheep at the local auto parts store or NAPA...

Just ordered mine.. Thanks for info guys... I am going to tap and install a port both before and after my turbo just to be able to move the probe from one to the other under the same driving conditions to see what the difference is on my truck M931A2 Cummins 8.3 .. I will relay the information...

Thank you sir for the info! I was planning on taping on the exhaust manifold, because the idea of small metal shavings going into the turbo scares me...... I'm still not sure if I want to do 2 taps like your doing (one on each side of the turbo) or just stick with one. If I do end up doing 2 I might end up buying 2 kits, so both temps can be displayed at the same time (or a switch to go back and forth from the front to the rear)... The more info I can get from the motor while its running the better off it is!

I'm not sure if it matters on a Pyro probe but with O2 Sensors it is best NOT TO install them in the lower part of a pipe (6 O-Clock Position) it may get moisture on it an give incorrect readings.. just a FYI...


Maxspeed3. I would not tap the turbo itself. Tap the exhaust manifold just before the turbo or the Exhaust pipe just after the turbo..

Thank you sir for the info! I was planning on taping on the exhaust manifold, because the idea of small metal shavings going into the turbo scares me...... I'm still not sure if I want to do 2 taps like your doing (one on each side of the turbo) or just stick with one. If I do end up doing 2 I might end up buying 2 kits, so both temps can be displayed at the same time (or a switch to go back and forth from the front to the rear)... The more info I can get from the motor while its running the better off it is!

 

[anthonyamato4]

is this gauge a 12 or 24 volt setup?

 

[Heath_h49008]

Either.