Jeep Enthusiast Forums banner

What's easier, remove y-pipe from exhaust manifold or separate y-pipe from cat?

2K views 5 replies 4 participants last post by  TheBoogieman 
#1 ·
Please excuse me if I use the wrong terminology, I'm new to this. I've been researching and can't find what I need, and when I do find something the third party pics are no longer available for viewing.

I'm want to add an AutoRust ART-131 Safe T Cap to repair my 2000 TJ's rusted frame.



The Safe T Cap instructions suggest disconnecting the exhaust system from the catalytic converter back. It looks like a tough job to separate the exhaust at that point, so I'm curious would it be easier to remove the entire exhaust by dropping it at the exhaust (not remove, but just allow me to drop it low enough to weld above it)?

For either option, could you guys offer some beginner advise for the process?

I asked in another thread how to remove the cat at the point in the photo below. Member mrblaine suggested "Cut the nut side almost flush, grind flush, punch out the bolt and replace with all new"

There is very little room, so how do I do this? Is this done with a grinder or dremel, or what do you suggest? And once out, do I replace with any nuts and bolts that fit the hole, or replace with OEM stock parts?

Sensitive content, not recommended for those under 18
Show Content


If I take it off at this point I'll still have about six inches of exhaust blocking the area I need to access. So, is there any play in y-pipe once it's separated at the above point?

Also, I'm planning to get a plasma cutter for this project. The plasma has gouging capability and with some practice I may be able to cut the nuts off with that.

Below is my view of the y-pipe to manifold. Any advise on this? I can shoot some PB up there, but I DEFINITELY don't want to damage anything. What's the procedure for this?



Thanks - Rick
 
See less See more
3
#2 ·
The picture where the Y pipe is connected to the 3rd cat, those nuts and bolts are definitely toast, take blaine's advice on that one, cut them off. I have a 90 degree 1/4" pneumatic die grinder with a cut off wheel that I really like for projects like what you're facing. I don't think I could get OEM replacements for my exhaust as the tail pipe side were threaded studs rather than true bolts.

The exhaust back from that joint should only be held on by some (2 maybe?) rubber hangers, they're kind of a pita but shouldn't be terrible. you may have to drop the transfer case skid and have the jeep on jack stands or ramps. You'll probably also have to do some twisting and turning to get it out.

If you're going to pull the Y pipe and the manifold just bare in mind that it's pretty likely that you're going to break at least 1 if not all of those bolts and their associate speed nut or u nut or whatever they are. I can't remember the exact name of them right now.
 
#3 ·
JeepnBlake, Thanks.

I spent most my day cutting the nuts, bolt heads, and threaded bolts out. What a PITA!!!!!

I drilled out one of my three holes, but my bits dulled and I had to stop. Going to sharpen and get the other two holes and then run some bolts through and tighten it down.

Now that I've separated the Y pipe from the third cat, I can see I definitely need to disconnect the Y Pipe from the manifold to get the room I need to weld the Safe T Cap in place.

If you're going to pull the Y pipe and the manifold just bare in mind that it's pretty likely that you're going to break at least 1 if not all of those bolts and their associate speed nut or u nut or whatever they are. I can't remember the exact name of them right now.
I've been soaking in Kroil and PB Blast for a couple days. I'm waiting for a set of swivel sockets to arrive and I'm going to try to drop the Y pipe. Can you tell me what to expect? How are the bolts attached? It looks like the heads are down with nuts at the top (manifold side). If so, is that nut going to cause me a problem when I try to reinstall? It looks like it's going to be tough to reach. Also, if (or when) I break those bolts, what will I need to do then? Will this mean I'll have to remove the manifold or drill them out? Also, is there a gasket between the manifold and the y pipe? I assume that will have to be replaced too.

Thanks.
 
#4 ·
I dropped the y-pipe on my WK and after all was said and done I wished I had ordered the OEM equivalent flange bolts and nuts prior to doing the job to have them ready when I put it all back together. I got access through the wheel wells on the WK. Looking at my TJ parts breakdown I see a splash guard you might be able to remove without wrecking it. Those flange nuts enable you remove and re-install the y-pipe with one wrench from below. The trick is to get the bolt started in the flange nut.

I kept losing the flange nuts trying to get the bolt started from below without a helper. Nothing like the sound of falling hardware going places you can't ever access. If I ever do work of the kind you are getting into I would have all new OEM or equivalent hardware with extras on hand before I start.

I was lucky I was able to find a set of flange nuts for a Dodge at Auto Zone that worked with my wife holding her finger on the nut so I could get the bolt started from below. Getting my skeptical wife to sit on a stool inside the wheel well of the WK and put her manicured finger on the flange bolt took some doing but she turned the tide in my favor.
 
  • Like
Reactions: RickDel73
#5 ·
I got the y pipe separated from the manifold. After two days of Kroil I was able to remove two bolts and I cut the other two off. Tight fit, but not that hard. The bolt and the nut easily separated after being cut. The replacement hardware I bought was a little too long, so I'm waiting for some 1 3/4" bolts to arrive from McMaster Carr before reinstalling.

I did try to remove the downstream CO2 sensors, but I gave up trying. I'm hoping I can get enough slack to get the room I need with them still connected. If not, I guess I'll try heat; although, there's a lot of oil, transmission fluid, and fuel lines near by, so I'm nervous to use an open flame by any of that.

My next step is trying to disconnect fuel lines and brake lines. I think I can do the job with the fuel tank still installed, but I'll open a new post for questions to these issues.

Thanks
 
#6 ·
I did try to remove the downstream CO2 sensors, but I gave up trying. I'm hoping I can get enough slack to get the room I need with them still connected. If not, I guess I'll try heat; although, there's a lot of oil, transmission fluid, and fuel lines near by, so I'm nervous to use an open flame by any of that.
I let the engine run to heat up the exhaust to remove my CO2 sensors.:D
 
  • Like
Reactions: RickDel73
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top