Help ...Screw Up Installing EGT on 2008 6.7L

[hwebster]

What a Bleeping Weekend!



Spent it doing some work that I've been wanting to do for some time. .



Major screw up tapping the manifold for the EGT. Had what appeared to be a good location and spent several hours carefully drilling out and tapping the casting for the EGT. I go to insert the probe and it stops 1/2 inch short!!!



So I tried to plug the hole with a 1/8 NPT plug and ended up screwing up the threads!



Truck is NS with an unplugged hole in the manifold.



Action plan at this time is -



1 - Purchase new 1/8NPT plug and try to block the unusable hole and relocate.



2 - If hole can't be plugged because the threads are stripped, I plan to re-bore it out and install a 1/4" npt cross over, add a short 1/8 nipple and try the probe with the additional gap from what ever I am hitting.



3 - If that fails. . Plug the new hole and relocate...



Any other suggestions??? I hope I haven't really screwed up!!!



ArrggggHHH!!!!



:{ #@$%!

 

[InfernoB]

Sounds like you've got it figured out on fixing it. Use Antiseize on the threads.

 

[LRutigliano]

What brand EGT probe are you trying to install?



Dipricol makes 2 different lengths... I had the same problem and installed the shorter length probe.



Please see my pics in my photos section of the TDR. Page 3.



p/n D 192 116 is for manifolds 1" to 2" in diameter (short probe)



p/n D 192 100 is for manifolds 3" and above in diameter (medium probe)



All DiPricol kits ship with the medium length probe...



Try cleaning up the 1/8NPT threads with the tap one more time before you go to the trouble of re-drilling larger. You may just have a bunged up thread. Use tap oil. 1/2 turn in, 1/4 turn out at a time. Use a magnet to get out the crud in the manifold.



Good luck...

 

[Coalsmoke]

Sorry to hear of the troubles.

Using the right thermocouple probe setup is definitely important as you unfortunately found out. If it were me, I would drill the hole 1/8" over what you have now, and tig weld on a new 1/8" NPT (27TPI if I remember correctly this is the thermocouple probe size) boss. You can buy these bosses, but you may have to just make your own. If welding is not an option for you, I'd make a plug and keep an eye out for a used, ebay'd or cheap stock exhaust manifold. You can get 1/4"NPT to 1/8"NPT OD to ID reducer, but I would be concerned about removing that much parent material from the exhaust manifold to stick the 1/4"NPT in there. The 1/8NPT tap size, if I remember correctly, uses a Q bit, which is 0. 3320" in diameter. So, instead of trying to put a pipe plug in there of the next size up, I'd probably stick a 7/16" SAE plug in, or standard thread if you prefer that terminology. This will at least buy you some time and get you back on the road. To bad you are not local to me, I'd be happy to help you out. Hopefully this will at least give you a couple more options. Keep on trucking

 

[CBari]

Been there done exactly what you did. I drilled it out and tapped it out to 1/4 then used 1/4 to 1/8 reducer. Worked fine and has lasted around 90k so far.



Could be worse when I retaped mine I thought I had a reducer with me and didn't, but it did have 1/4 plug so I screwed it in only to realize that I had grabbed a 1/8 plug and screwed in till it fell all the way in and down in the turbo.



Needless to say I had to pull turbo off to get the plug out. The one benefit was that I was able to get a little piece of mind that I didn't have any fillings that had gotten into the turbo.



Just remember that tomorrow is another day.

 

[HLewallen]

Does anyone make a cool new aftermarket exhaust manifold for 6. 7s? Might be a good excuse to upgrade . . .

 

[hwebster]

Problem Solved - Right Tool Right Job

Well it definitely took the right tool! Had to scramble to find a 7/16" bit with a 3/8" chuck to get the right angle drill to fit in there. Added a 1/4" - 1/8" reducer, the NPT/NC connector and the thermocouple. Got her done!!!:-laf

 

[Coalsmoke]

Glad to hear you got it licked

 

[HLewallen]

Nice job. Nothing like hard earned victory!

 

[hwebster]

Lessons Learned

The EGT was only one of the things installed this weekend. I also tossed on a cat 5 hitch and brake control. As per syllabus - there were problems and a few revelations. I always wondered how you got the bolt into the hole in the frame, almost 2 feet from the end of the frame member.



Who knew a little piece of spring steel with a coil on the end to attach the bolt was so cool!



Of course the right tool for the right job always helps. Given things were so muddy I hosed the truck of in the dark... Now it looks like it was hosed off in the dark!!



Thanks Folks!!!