Well what way to end a day…I was just finishing the installation of my EGT gauge and just started to remove the factory installed plug from the Jacobs/Dodge engine brake system located on a small curved cast iron pipe post turbo. While attempting to remove the threaded plug it appears to be stuck, galled, cross threaded ??????

I first used a box end wrench to remove the plug and it just started to move. Due to limited access I attacked the plug from below with a socket, extension and flex handle wrench.
The plug would not move. So I decided to use my air driven impact wrench, I did use the correct rotation and correct size socket to remove the plug.

Well the plug would not move at all but the socket rounded off the plug. It appears the plug was cross threaded at the factory, galled its self into the exhaust pipe or who knows what.

Does anyone have any suggestions for removing this STUCK plug?

And I thought this was going to be so easy especially purchasing the Dodge/Jacobs system when I purchased the truck. I thought having the pre drilled EGT sensor hole already drilled was such a good thing. I have not called the dealer yet, I’m sure they will take no responsibility AT ALL. Any suggestions???
Thanks in advance.

I used the factory single gauge A pillar Dodge factory mount for the gauge, looks great...

Now I am frustrated......

 

they have a high temp locktite put on them that you have to put some serious torch heat to get loose i found this out after i did they same thing as you thats why my probe ended up in the manifold

 

Well if vise grips don't work what about drilling a new hole and tapping it to fit the sensor? You could always drill it out and re-tap to a larger size and bush the sensor too. Removing it would probably be a much better and easier way to work on it.

 

Hi,

I also had great difficulty in removing the plug. It appears to be partially cast in place. When I finally removed the plug the end of it was torn metal, but the threads were intact and I was able to install the bushing and sensor probe for the Quad Commander. I put a small amount of Never Seize on the bushing and sensor probe before installation. No leaks were seen, as evidenced by the lack of carbon traces around the hole.

It will come out, just *very* hard.

 

Walt... Sounds like you are doing exactly what I'm gonna do to my truck. E-Brake, single pod guage with egt and boost combo guage...
On pipe threads, the best luck I ever have with them is to "warm it up" first. That doesn't have to be a torch, just take a 2-3 pound hammer and hit it SQUARELY on the head several times. It tends to shock the threads and cause them to loosen up slightly. Then, used a 6 point socket and a ratchet and don't be scared to "put out" on it. If the plug is in a location thats hard to reach directly with a hammer, you might have to use a 3/8 drive extension or a good heavy punch to hit it with.
If the plug has already started rounding off, get a 6 point metric socket and drive it onto the plug. I've removed 1 inch exhaust plugs that have been in manifolds for 10 years using this method. Impacts tend to round off the head if the plug doesn't start turning prety quick, so try using a ratchet if at all possible. I actually use a 1/2 inch drive extended handle ratchet with an adapter to 3/8 for little plugs like that. Just be patient and it will come out.

 

carharttfarmer is correct. It has high strength loctite on it and will require heat to remove without damage. I wish I had known that when it was sitting on the bench.

 

Thanks for this info, I'll give it a try. I will need to find a metric socket that I can force fit onto the rounded plug. What a mess... I don't unserstand why the plug is so tight....

 

walt

why not just drill the exhaust manifold? it will give you a more accruate temp reading. i thought about having an post-turbo pyro in conjunction with my pre-turbo,but after reading this im going to reconsider

brett

 

prabable thought the same thing i did ill roll under there take the plug out and be done in ten minutes
dealer put mine in the manifold for 40 bucks

 

Well I followed the directions posted, used a 14 mm socket and worked it out. Like others are reporting many threads followed on the plug. Looks like a POOR design. Does anyone have an idea what the proper pitch and diameter of the hole is so I can clean out the threads with a tap.

I can't thank all of you enough for your asistance with this frustrating issue. I really think Jacobs/Cummins has a design problem with this plug.

 

Probably just a 1/4 inch national pipe thread.

 

Well used a 1/4" 18pitch NTP tap and cleaned up the hole. the thermocouple screwed on just fine and there appears to be no leaks. I used some anti seize compound on the threads and all is good.

Thanks for all the assistance

.

 

One thing I forgot to mention..... When tightening a pipe thread connection into the exhaust system(or cooling system) don't get too agressive with the wrench. Run it in finger tight, then give it about a 1/2 to 3/4 turn and leave it. A little tighter on cooling system, but not much. The threads want to "grow together" in the heat, and even if it isn't completely sealed at first, the exhaust soot will finish sealing it up. (I do this on natural gas engines that run thermocouples on every exhaust port, pre turbox2, post turbo...etc..) It makes life alot simpler when/if you ever have to remove it.
I'd like to know how you like your E-Brake....Pros-Cons... are you running it on a 48RE or manual? How does warranty feel about the E-Brake?.. Thanks

 

warranty fine with the jacobs i like mine alot the only con for me is the hissing sound it makes when your outside the truck

 

I contacted Jacobs Customer Support regarding the plug issue. They said no problem with warranty if I take the truck into the delaership. It looks like I resolved it myself but it's nice to know that Jacobs will stand behind their product.