Removing EGR Tube -- Hints?

[Lem Forder]

I'm trying to get my '87 MM 2.6L 4X4 back on the road after sitting for many years. I am trying to be diligent about flushing and replacing fluids and cleaning out the crap from nearly 30 years of deferred maintenance. I'm trying to get the EGR tube off so I can clean that out as Camoit recommends, but can't get the lower connector to budge. I don't have a 32 mm wrench, go tried a crescent wrench with a long breaker, but still no movement. I soaked it for two days with liquid wrench and tried heating with a heat gun. Nothing. I'm afraid I'm going to round off the nut and never be able to get it off. Any tips or tricks I'm missing?

[royster]

I'm simply going to be a voice of support, Lem, because I know nothing about the 2.6. It sounds like the EGR tube is going to get destroyed in order to procede, meaning you'll need to locate another one. I've heard of people just eliminating the EGR altogether.

We'll just wait for the Voice Of Experience to show up. Meanwhile, have another donut, I'll brew some coffee and we can discuss the virtues of '94 Sport models! :)

[Lem Forder]

Thanks Roy. I decided I'm going to head to Sears and pick-up a 32 mm wrench. Then try to find my propane torch and have at it. Wish me luck.

I'm waiting to hear back on the Sport. Hope to go see it this weekend.

[royster]

Metric wrenches are sort of fickle. I bought some from Lowe's, and the range jumps from 19mm to 24. I've had to fill in the missing pieces by hook or by crook. The good news is you only have to buy them once (in theory).

Hope all goes well with the sport: if you DO get it, be sure to post the link and some photos: a lot of people here will be quite envious of that little treasure.

And hope all goes well removing the pipe. I have used my Dremil tool with a small wire wheel to try and get rust off the ends of the bolts that have been rusted on. (Anyone looking to remove their windsheild wiper pivots are in for some real cussing, as it is a rivit with a bolt head. Barely enough room for pliers inside the firewall cavern. I was trying to take mine off just for maintenance and never DID get the driver's side off).

[Lem Forder]

Damn! The 32 mm is too big. I'm going back for a 30 mm. I have 1 1/8" that is too small, so I figured 32 mm would be right -- nope. 30 mm is equivalent to 1 3/16", let's hope that's it.

[crvtec90]

Good luck with the liquid wrench. I swear by PB Blaster. I don't think a heat gun will get it hot enough so good move on the propane torch. Do you have to pass smog? If not You might think about just deleting egr.

[Lem Forder]

ARRRGH! Well, got the 30mm and it is the right size. Unfortunately, it looks like I rounded off the shoulders on the head too much and it won't grab. So, it looks like the pipe wrench is going to have to be it. Thanks crvtech, I'll try some PB Blaster and marinate it over night, then hit it with the torch in the AM. But, I'm thinking about going the delete route anyhow. I opened up my valve and found that it's non-functional. The rubber diaphragm is toast. From what I can see, it can't be repaired. It looks like a new replacement will run $125 to $200. I read in the Chilton's manual that an inoperative egr valve can cause detonation at highway speeds when carrying a lot of weight. Anyone experienced that?

[ratesheet]

Yep...IMHO, some very good advise previously mentioned here....let me throw in my 2 cents....for over 30 years I have been a service plumber and currently a heavy equipment mechanic working on military vehicles....my first suggestion is PATIENCE!!...if the truck sat for a few years a few more days or a week won't hurt...I also swear by PBlaster...let it do it's work and you'll be amazed...also, once you've soaked the area with PBlaster occasionally tap the nut and surrounding area with a hammer, the impact will create microscopic fractures in the corrosion and allow PBlaster to further penetrate...remember heat will expand metal and in some cases make it harder to remove the part...currently at work I have 2 1" metal dowels encased in 4" rubber that were supporting a 10 ton dump truck, they (the dowels) are encased in rust...I'm letting them soak over the weekend to make the removal of the dowels easier, that is standard procedure among mechanics in the disassembly of gov't vehicles...if by chance the nut is rounded off too far at that point I'd drill a hole in the center of the nut and get a high quality easy out and let that work, it'd be similar to a hex bolt...again just my 2 cents...good luck.

[Lem Forder]

Thanks Rate -- Patience is a virtue that is in short supply right now. But, I know you're right. I did let it go for the day today and you've convinced me to leave alone tomorrow too. I'll keep up the PB basting and tapping for a day and try it again on Monday. I might try heating it and just letting it cool a couple of times. Seems like that should help open things up a bit to let the PB penetrate. That make sense? I don't know the right terminology, but what I'm working on is like a large fuel line -- a flared 1/2" steel pipe with a threaded brass collar that connects it to the exhaust. A giant flare nut wrench would have been the perfect tool, but that apparently doesn't exist, at least at a price I would consider. So, I think a pipe wrench is my only remaining option. The real bummer is that I figured this was one of those that sounded like a good thing, but not necessary. Oh well, I'm sure I'll feel better when it's all said and done. Thanks for the input.

[Law Dog]

I used a pipe wrench and an extension pipe to get mine off the exhaust manifold the top one is the one that sticks and the EGR breaks taking it apart.

I have a couple new tubes if you need one.

[crvtec90]

You can get it pretty hot before its hurt ( its in the exhaust after all) but I wouldn't recommend trying to loosen it while its hot since it expands. The heating will make it expand and contract when cool. I would heat the area around it more than the nut itself.

Propane in the blue bottle is okay. Ive been using the map gas in the yellow bottle ( from home depot or lowes) which gets hotter.

If I remember correctly the egr valve has spring tension and uses exhaust back pressure to open it. The vacuum just helps it out. If your spring is worn out it will open prematurely regardless of the vacuum diaphragm.

My egr is deleted and Ive had no troubles to speak of. And since your diaphragm is shot the egr system wont be functioning properly anyhow. I bought a fancy egr block off plate from ebay but you could make your own. If you can get the egr valve off the intake manifold you can make a block off plate from a thin sheet of aluminum like a cut up soda can or gutter. Just use the egr valve gasket as a template, cut the aluminum so that it blocks aff the passages and then bolt the egr valve back on over it.

[Law Dog]

Looked in the shed and found a tube and EGR valve still on a manifold I put a Weber on mine so I removed it from mine.

[Rymar Garage]

I just cut it off and welded a plate over the hole, like 10 min ago. lucky for you the 2.6l have an aftermarket header available and the 2.0 does not. i have ordered and returned 2 sets of pacesetters and both way off and they said that was the only thing they had. Im in the process of right now deleting all that mess that goes along with the egr

[camoit]

The large tube on the exhaust manifold is a cold air injection tube. Not the EGR. The EGR is on the intake under the carb. To pull off the air tube it's best to heat the manifold with an oxy acetylene torch around the nut. It will take a bunch of heat to make it break loose.
If you get it out you can use a plug to fill the hole.

[Lem Forder]

Thanks for all the replies. I'll store all that on my brain's hard drive. I screwed up and as Camoit deduced, I was working on the wrong thing. DOH! When I get to the EGR, you'll probably be hearing from me again. So, my question now is what the hell am I working on? I looked in both the Chiltons and Haynes manuals and can't find any reference to it. What does it do? Camoit calls it a cold air injection system. It sends cool air to the manifold? What for? I think there's a vacuum actuated valve that seems to be non-functional on my engine. The diaphragm looks like it's shot. Should I worry about it or just put it back together? Thanks

[pennyman1]

it injects o2 into the exhaust to dilute the gases and to make the cat work better. the big valve on the other end of the pipe is a reed valve that pulls the air into the manifold on each exhaust pulse, then closes. If the carb is working, you don't need it, unless you have visual emissions inspections. Geronimo's has been gone since 1983, when I put the first header on him.

[Lem Forder]

Thanks Pennyman. So, the reed valve is a one-way valve? Lets the cold air in when there's a draw, right? What does the vacuum valve do? Sounds like it really doesn't matter, just curious.

[pennyman1]

Yes the reed valve is one way - like the reed valves on a 2 cycle lawn boy mower. The vacuum valve controls other emissions pieces - depending on which one, it will not apply vacuum until the motor is up to operating temp.