I am installing new obx stainless shorty headers on my 01 5.4 4x4, and I am having some problems. I went to mount the egr valve back up to the bunion on the header, and the threads on the fitting connected to the egr valve will not screw into the header. I took a 3/4" nipple and it threaded in there perfectly, so the threads on the bunion are different than the fitting of the egr valve.... Any suggestions?

 

Considering that you "just got these"....you maybe wise to contact OBX directly...& start asking questions there. It maybe that they got a bad bunion?? Or, welded the wrong one on for your application, say, maybe they welded a 18mm on instead the standard 3/4"?

If that be the case, they should send/exchange you for the correct one.

 

the sad thing is, is they are already on. i just emailed obx, and hopefully i get a response soon... I have been thinking about plugging it, and just deleting the egr completely.. should i or no?

 

contacting the manufacture is good...they should take care of you, part of customer service.

Pretty sure you could delete it....but if you have any kind of vehicle inspections...that probably won't fly. & you would have to most likely reprogram the ECM.

maybe a good muffler shop can offer up a flexible EGR tube/ adapter

 

The correct adapter will NOT leak. ANYTHING else will.


http://www.oreillyauto.com/site/c/de...rd=egr+fitting
This will fit 97-03.

 

Oh the bung isn't right ? Sorry, yea the 5.4L's use a 3/4" (.75)/19mm bung for the EGR.

A 4.6L bung is quite a bit smaller. 15 or 17 mm I can't remember which, but it is smaller and some have a different type connector vs others.

Ford uses 3/4" NPT pipe thread type. The difference in sizes is very obvious. Meaning there's nothing in between or a little this way or the other. It'll be 1/4" (.25) either way. So yea, the wrong size should be obvious.

NPT works like this, 2-3 turns/revolutions by hand before jam, 1-2 turns for seal.

You may have to take a small file to the start thread. Sometimes they get buggered. If OBX has it wrong, it would be off by a mile and not just a little. Unless they used a fine thread which is very doubtful. You post above that the 3/4" threads in fine, so that only leaves the adapter threads being a little messed up. I'm not sure what else could be wrong ?

I do know that removing/exchanging headers would be a PITA. Tuning out the EGR (EGR delete) has NO advantage other than cleaning up the engine compartment. You may loose a bit of economy without that valve. However if you do indeed choose this route, make sure you get the correct "bung plugs" as they are made with a cap washer incorporated and will not leak.

Maybe you just need to give it another shot.

 

The nipple on the headers is a 3/4 JIC (witch is jic-1&1/6-12), the threads on the stock egr tube is M22x1.5 . My solution was , order an M22x1.5 to 3/4 npt adapter , then a 3/4 npt to 3/4 JIC adapter. Bang issue solved