2nd Gen Non-Engine/Transmission Isspro Pyro Install

[keimmmo]

I am in the process of installing gauges on the 01. 5. Today I drilled and tapped the hole in the exhaust manifold for the pyro... no problem. I am used to fixing the unrepairable and making things that do not exist down here!



I went to install the pyro and discovered a problem! From the top of my manifold to the floor inside is 2 inches. The pyro was 3 inches long. Now, that AIN'T going to work!!! I had all kinds of thoughts going through my mind! I bought the gauges in Illinois and here I am in Mexico! What am I going to do???



I have never read about this problem in the forums! I was about to write and ask for help. I picked up the box the pryo came in to have the part number. That is when I noticed it is an ADJUSTABLE thermocouple!!! I played with it for a second and realized that the length IS adjustable! I installed it so the tip is about 1/16 from the floor of the manifold.



Again, with all the reading I have done getting ready for this install, I had never read anything about this situation. Hopefully this will help someone else with their install.



Steve

 

[dieselshu]

Isspro pyro thermocouple

K, you hit the nail on the head, it is adjustable initially, but once you tighten down on the ferrule nut. . it stays at that height, because the ferrule gets clamped down onto the thermocouple.

Enjoy your gauge!



DavidOo.

 

[Boondocker]

thermocouple tightness

I have the same thing. My tap job was a tiny bit to big, it seals tight, just afraid to torque it too much. So now I'm in the habit of checking it with an adjustable wrench at every fuel up. I feel the need to open the hood and gaze upon the Cummins anyway.



For the record, the thermocouple loosened and popped out once before I got in the habit of checking it regularly. I was on a towing trip up and down hills and the egts were fluctuating 1000 degrees depending on grade and load. Big chuffing air leak when it popped off, just put it back on - no problem.



Neil

 

[keimmmo]

The tapped hole in the manifold is not a problem. I was aware of the problem of tapping a pipe thread too big long before I became a member of TDR. I still have a couple of threads sticking out of the top of the manifold. I had measured the thickness of the manifold and the bottom of the fitting is just about flush with the inside of the manifold. If it doesn't go in far enough and is holding by only a thread or two, it is weak and prone to leak. If it goes in too far, it might not tighten well and creates an extra bump that will slightly affect exhaust flow. That probe is bad enough! I hate anything that hurts the flow! However, in this case, I would rather have the information the probe gives me than the flow I would gain without it!



My original problem was that I didn't realize the length of the probe was adjustable and was trying to figure out how to put a 3 inch long probe in a hole that was only 2 inches deep! I now have it installed and tightened and have run the motor. All seems fine. However, I will be checking all new connections for all the new gauges until I am sure that everything is leak free!!!



Steve