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H. Miller · 07-31-2013, 02:35 PM

ISC 8.3L engine.. Where does the engine computer get EGT info if no EGT guage is installed? It limits temp to 1200 deg. so must get info from somewhere!
The problem arises when replacing exh. manifold and there is a guage previously installed. It seems that a hole drilled in the new exh. manifold (for the sensor) will nullify the manifold warranty !!! Even with Cummins doing the work...
Thinking of mounting the sensor AFTER the turbo???

spike45 · 07-31-2013, 07:21 PM

Quote:

Originally Posted by H. Miller

ISC 8.3L engine.. Where does the engine computer get EGT info if no EGT guage is installed? It limits temp to 1200 deg. so must get info from somewhere!
The problem arises when replacing exh. manifold and there is a guage previously installed. It seems that a hole drilled in the new exh. manifold (for the sensor) will nullify the manifold warranty !!! Even with Cummins doing the work...
Thinking of mounting the sensor AFTER the turbo???

Mr. Miller,

While it seems like a good idea, the problem will be that the temperature after the exhaust turbine housing will be lower leading you to flog it harder until that temp hits the 1200 degree range while the before temp will be perhaps 200 degrees higher.

Are you replacing your exhaust manifold due to cracking of a one-piece design with the updated 2 piece design?

road dogs · 07-31-2013, 07:30 PM

I have never heard of an exhaust manifold failing unless it cracked due to inept TC drilling & tapping, although it sounds like yours must have failed for some reason. When I installed my EGT gauge I drilled & tapped both a 1/8" NPT and 1/4" NPT and plugged the one I didn't use. Exhaust manifold is the only place you will get a true real-time EGT measurement, I wouldn't monitor it any other place or you will always be wondering if it's too high or not.

H. Miller · 08-01-2013, 06:13 AM

Replacement of our TWO piece exh. manifold is due to an obvious leak and a "run out" measurement at twice that allowed by Cummins. Yes the old manifold can be ground flat but Austin Cummins say they are not allowed to have that done and further, they can drill the manifold for the sensor but will void the manifold warranty. (engine warranty is long gone)
The engine is computerized and engine exhaust is maxed at 1200 degrees (it won't go any higher). The leak caused the temp to hover around the 1200 deg. mark much more than previous. I figured the new sensor location might change the sensor temp but that will become my new max temp.
REAL QUESTION is where does the engine computer get it's temp reading to be able hold the temp at 1200 deg. as the EGT guage is an entirely different (not connected) system added by me last year.
As a point of interest, neither the Silverleaf nor the Scan Guage D offer the EGT (pyrometer) reading as an option...

Triker56 · 08-01-2013, 07:10 AM

Quote:

I have never heard of an exhaust manifold failing unless it cracked due to inept TC drilling & tapping, although it sounds like yours must have failed for some reason.

Having a cracked manifold happens a lot with the Cummins engines. A lot of them don't even have the drilling done on them.

Do a research on replacement manifolds for them and you will find a lot of after market ones. They wouldn't be available if they wasn't a demand for them.

My 2 piece one has been replaced once.

hillboy · 08-01-2013, 02:39 PM

My 2cents.... I had a 5.9 Cummins and installed the EGT after the turbo. I used 900* as my top number. Watch the turbo cool at idle is a handy thing, and I am about to install an EGT in my 350 ISC.

Not sure what limits the exhaust manifold to 1200* in an ISC as stated in a earlier post. Is that Cummins info?

Coma · 08-02-2013, 04:59 AM

Quote:

Originally Posted by H. Miller

ISC 8.3L engine.. Where does the engine computer get EGT info if no EGT guage is installed? It limits temp to 1200 deg. so must get info from somewhere!

I don't believe that it is limited. In other words, in stock configuration, under extreme conditions you will see EGT excursions above 1200. That is the way the Duramax operates. The other option is that Cummins testing show that under all normal operating condition EGT never exceeds XXXX, which is something the motor lives with. Small, Short duration excursions in EGT don't generally have ill effect.

After turbo temp is not what the pistons see and you can't simply add x degrees because you don't know how much work the turbo is extracting. Work extraction from the exhaust is what causes the temperature drop across the turbo.

Dr4Film · 08-02-2013, 08:04 AM

I just had a Banks Power Pack installed on my ISC 350HP Cummins yesterday.

I have two new gauges that came with the kit, an EGT and Boost gauge. The EGT sensor was installed into the exhaust manifold. The information that is fed to the gauges comes from the Power Pack Ottomind module.

The Ottomind maxes out the EGT at 1300F. That's when the module will back off and reduce the fuel supply regardless of your pedal position.

The Boost is now about 32 lb's whereas the Boost gauge from the Cummins VIM and SilverLeaf read a maximum of 24.4 lb's.

Dr4Film ----- Richard

jlfbatonrg · 08-02-2013, 07:15 PM

I also added an EGT gauge and placed the sensor after the Turbo on the advice of Cummins. As has been stated, I monitor the temps closely in the mountains and don't let the EGT temps get over 900 degrees. Has worked fine for me for three years now.

Robar · 08-02-2013, 08:38 PM

Could someone provide a little more information about the EGT gauge for the Cummins 8.3 ISC. Does the pyrometer probe mount with a weld-in bung, a pipe tapped hole, or a drilled hole and hose clamp. Is it difficult to install? Do you have to buy the special MH kits with the 55 foot thermocouple? How and where do you hook in the boost gauge if you buy the combo unit?

Thanks

Dr4Film · 08-02-2013, 08:48 PM

The Banks EGT thermo sensor was installed into the exhaust manifold with a drilled and tapped hole.

it then went to a fuel control module and another cable to the front of the coach that went into the gauge.

If installing a separate one, I would say the sensor installation would be the same and you would just have to make sure that you can extend the wire leads long enough to reach the dash area or wherever you are going to install the gauge.

Dr4Film ----- Richard

H. Miller · 08-03-2013, 04:57 AM

Quote:

Originally Posted by Robar

Could someone provide a little more information about the EGT gauge for the Cummins 8.3 ISC. Does the pyrometer probe mount with a weld-in bung, a pipe tapped hole, or a drilled hole and hose clamp. Is it difficult to install? Do you have to buy the special MH kits with the 55 foot thermocouple? How and where do you hook in the boost gauge if you buy the combo unit?

Thanks

The pyrometer probe when mounted in the exhaust manifold is in a drilled and tapped hole. You'll basically need to remove the turbo to MAKE SURE no small pieces enter the turbo. To mount after the turbo required welding a fitting into that exhaust piece. BEWARE it's stainless and not welded by your average "shade tree".
Got ours back yesterday and one excursion to 900 deg with normal max at 800 deg was all we saw in 20 miles of city traffic with 100F OAT... So it appears that 900 is what I'll be looking for as my new max.

jlfbatonrg · 08-03-2013, 09:15 AM

I purchased my EGT kit off the internet for a Dodge Cummins ISB engine. Before installing I checked with the gauge manufactuer to determine if I could extend the sensor leads. They said yes, to use a 14 gauge wire. I then contacted Cummins to determine the correct location for the sensor. They said 2-3 inches after the turbo. I drilled a 1/8 inch hole in that location, then fabrcated a curved piece of 1/4 inch thick by 3 inches by 1.5 inches stainless stock and tapped it to fit the threads of the sensor.. I cleaned the area on the exhaust pipe, carefully matched the curvature of the pipe, then mated the 2 pieces and secured them with 2 hose clamps. I threaded the sensor into the tapped hole which was directly over the hole in the pipe. After installation, I checked for leakage by using liquid soap and starting the engine. I have been using this set up now for 3 years without problems.

jlfbatonrg · 08-03-2013, 09:17 AM

Robar,

You may already have a boost gauge sensor on your engine if it is computer controlled. Our 03 did. I purchased a ScanGauge D monitor and it picked up the boost pressure from the engine diagnostic plug.