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Discussion Starter #1
OK, first off thanks to everyone who helped out with pointers, insight and info. Miesk, Abandoned, and many others. Thank You.

OK, I've known I needed a new exhaust system for a little while after crawling under and seeing black sooty residue along the exhaust.

So I asked a ton of questions, started a few threads, searched here and FTE, asked even more questions, Shopped online, found good deals, planned, planned, planned. Finally figured out what I needed and ordered the parts as money and time allowed. Along the line, there were different specials and discounts on the items I needed so I bought when the buying was good.

Started off getting the Dynomax Cat Back Exhaust Part # 17410. It's a 2 1/2 exhaust which is up from the factory 2 1/4. I decided to go ahead and install it as is and get the rest of the system later as money allowed.

Problem #1 I discovered that the Cat Back system is about 5 inched too long between the hanger locations and the factory Catalytic Converters. There was some other sales going on with Catalytic converters and other items I needed so I went ahead and bought them also. I bought the Walker Catalytic Converter #15042 and the Walker YPipe #45166. I also got a new Bosch O2 Sensor while I was doing this.

Now Problem #2: The YPipe. Built by Walker, the quality isn't that great, but, it's not a $2-300 Mandrel bent pipe either. Around $50 with a discount from Advance Auto and it was shipped from the main warehouse in Tennessee. Once it arrives I see this on the rear exhaust tube.

Looks like they knocked a hole in it and then welded the pipe over the hole. A few minutes with a Drill, some oil and a 1 3/4" Hole say and it now looks like this.


I don't have it installed yet. That will come on my next weekend off. I will take more photos and walk through the install as I go. I'm using Band Clamps for the install instead of welding. So far after a rough test fit, everything is lap joint fitted except for the connection between the Muffler and Catalytic Converter. That'll be a Butt Joint. Here's the components so far on my messy table in the Garage.


More to come. Here's the current parts list.
DynoMax 17410 Cat Back Exhaust system
Walker 15042 Catalytic Converter
Walker 45166 Y Pipe
Bosch O2 Sensor 15718
Preformed 2 ½ Strap Band Clamp SS BK7333220
Flat 2 ½ Strap Band Clamp SS BK7333958
 

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def. interested! was begining to think my 4.9 FSB was an extinct or quickly dying breed!? any other modifications fromt he past? or plans for the future?
 

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Discussion Starter #3
Not really. I Plan to keep it fairly stock. This new system will only have a single converter whereas the OEM had 2 inline. It's 1/4" larger so in theory it should flow better. From everything I've read here and FordSix.com, and FordTruckEnthusiast.com, you really don't want to go to large on the exhaust or else you loose low end torque which is the main thing about these engines. I may cut the flattened, box shaped end off the tailpipe and replace it with a larger round one. Nothing major. The key is that when I'm done, I'll have a total and completely new exhaust system from the manifolds back.
 

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Heya John,
Glad things are coming together! Looking good.
That hole in the Walker pipe is, unfortunately, one of those things I wish I'd known about BEFORE I installed mine. Mine still has that poor quality obstruction in it.

The 2.5" exhaust really seems just about right for these engines. Granted, 2.5" was a huge upgrade from the 1 7/8" they had on the carb'd motors. :smilie_slap

You did things the smart way. Research, plan, research plan, plan, plan. It's how I've done my projects, and I've never been sorry. Costs a lot less money in the end! :thumbup
 

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Discussion Starter #5
Here's the install and alignment instructions from the 96 Workshop manual. Thanks again to Miesk for getting them for me. I read these in a previous post a year or so ago but could not find them again until he resent them to me.

from 96 Workshop Manual
Inspect exhaust inlet pipes (5246) and mufflers (5230) for cracked joints, broken welds and corrosion damage that would result in a leaking exhaust system. Inspect the muffler pipe brackets (5277) and exhaust outlet pipe frame brackets (5260) for cracks and stripped or badly corroded bolt threads. When muffler pipe brackets are loosened and/or removed to replace a heat shield, exhaust inlet pipe or muffler, replace the muffler pipe brackets if there is reasonable doubt that their service life is limited.

NOTE: Mufflers are designed with drain holes. However, it is normal for a certain amount of moisture and staining to be present around the seams of the muffler. The presence of soot, surface rust, or moisture does not indicate a damaged muffler and should not constitute the basis for replacement.
Muffler clamps can be broken due to overtightening. When attempting to eliminate exhaust leaks at joints, tighten muffler clamp to specification. Do not overtighten bolts or nuts to correct a leak. If this does not eliminate the leak, the clamp should be loosened, rotated approximately one-quarter turn, and then retightened to specification.
The exhaust system, including heat shields, must be free of leaks, binding, grounding and excessive vibrations.
These conditions are usually caused by loose, broken or misaligned muffler pipe brackets, shields, exhaust outlet pipe frame brackets or other exhaust components. If any of these conditions exist, check the exhaust system components and their alignment. Align or replace as necessary.

Exhaust System Alignment
Perform the following procedures to align the complete exhaust system:
Loosen the pipe connection clamps and the muffler pipe bracket clamps. Loosen the flange-to-exhaust manifold nuts.
Work from the front and progressively align the exhaust system components and exhaust outlet pipe frame brackets (5260) to eliminate any interferences. Make sure that aligning tabs (if used) are fully engaged in their mating slots.
Then, working from the rear forward, retighten clamps to specifications. Finally, tighten the flange-to-exhaust manifold nuts alternately and equally to specifications so that the pressure on the ball flange will be uniform.

Noise, Loose Catalytic Converter or Muffler Heat ShieldsNOTE: While idling or during normal driving conditions, a buzz or rattle may be detected, which can be traced to the exhaust system. The heat shield attachment to the muffler (5230) or catalytic converter may come free. The loose heat shield will vibrate off the muffler or catalytic converter and cause the buzz or rattle.
Diagnosis and Repair
NOTE: The catalytic converter may have two cans. If shields on both cans are loose, four clamps (two for each) will be required.
Attach two band clamps (Part No. 383735-S) to the catalytic converter or muffler as shown. Tighten to 7 Nm (60 lb-in).
Align the clamp to secure the heat shield to the muffler or catalytic converter. Tighten the clamp to no more than 7 Nm (60 lb-in).
Trim excess "ear" to approximately 25mm (1 inch).
Securing Heat Shields, Typical

Catalytic Converter, Gasoline EnginesRemoval; CAUTION: When servicing the exhaust system or removing exhaust components, disconnect all heated exhaust oxygen sensors at the wiring connectors to prevent damage to the sensors and wiring harness.
Raise and support the vehicle.
Remove the muffler (5230) and muffler inlet pipe (5A212) (if applicable).
Disconnect, if applicable, the air inlet tube from the catalytic converter.
Remove the exhaust manifold-to-catalytic converter nuts on all but 5.8L manual transmission (7003) and C-6 automatic transmission Chassis Cab.
Remove the inlet pipe-to-converter nuts on 5.8L manual transmission and C-6 automatic transmission Chassis Cab.
Remove the catalytic converter from the vehicle.
To install, reverse the removal procedure. Tighten the exhaust manifold-to-catalytic converter or exhaust manifold-to-inlet pipe nuts to 34-46 Nm (25-34 lb-ft).

Exhaust Inlet Pipe
Remove the muffler (5230),muffler inlet pipe (5A212) and catalytic converter.
Remove exhaust manifold-to-exhaust inlet pipe nuts.
Remove the exhaust inlet pipe (5246) from the vehicle.
To install, perform the removal procedure in reverse order. Tighten the RH exhaust manifold-to-exhaust inlet pipe nut halfway, tighten the LH nut to 34-46 Nm (25-34 lb-ft) and tighten the RH nut to 34-46 Nm (25-34 lb-ft).


Muffler Inlet Pipe
Remove the muffler (5230). Refer to Muffler in the Removal and Installation portion of this section.
Remove the U-bolt clamp at the muffler inlet pipe-to-catalytic converter connection.
NOTE: It may be necessary to heat the muffler inlet pipe-to-catalytic converter joint to break it free.
Remove the muffler inlet pipe (5A212) from the vehicle.
To install, reverse the removal procedure. Tighten the U-bolt clamp to 54-71 Nm (40-52 lb-ft).

Muffler
The exhaust system components are removed, disassembled, assembled and installed using standard tools and procedures. Only remove components to the extent necessary to replace worn or damaged components.
Always refer to the Master Parts Catalog for parts usage and interchangeability before replacing a component part of the exhaust system.
Removal
Remove U-bolt clamp at the muffler input. On Bronco, disconnect flat flange.
Remove the muffler (5230) from the rubber supports at crossmember and frame (5005).
Remove muffler. It may be necessary to heat the muffler/converter joint in order to separate the muffler from the catalytic converter.
Installation
Place muffler in vehicle by sliding it over axle housing.
Position muffler by inserting over the end of the catalytic converter and aligning slot to tab on catalytic converter.
Apply a soap solution to metal support rods on muffler and catalytic converter. Avoid use of oils or silicone since they do not dry and may allow the insulator to slip back off once it is installed.
Force metal support rods through rubber insulators.
Install the U-bolt clamp (U/8500 GVW F-Series/Bronco) and tighten to 54-71 Nm (40-52 lb-ft). On Bronco, install flat flange bolts and tighten to 34-46 Nm (26-34 lb-ft). Tighten nuts sequentially in a criss-cross fashion. Tighten first nut to half torque, then second nut to half torque, then third nut to half-torque, then tighten all nuts to specification.
 

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Discussion Starter #6
Two things Noticed so far with differences between OEM and this hew system.

The old Muffler Heat shield will not fit the new muffler. I'm looking at it now to see how I might retrofit it.

Also, for some reason, the bolt that comes with the muffler in the 17410 Cat Back kit, which is the Dynomax 17785 muffler, isn't long enough to use on the hanger for the muffler.


OK, I think, with the use of a pop riveter and a bend strap I can make this work.

You can see the rear bracket used in the F150 hanger setup doesn't allow for either of the bolt holes on the Shield to be used. I think I should be able to cut a large hose clamp and connect it to the other side just like the OEM clamp it should hold it well enough and not cause any rattle.
 

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I've never used a heat shield on mine (and my stock one didn't have one). I also had a shop go through my system to "tighten it up" and they never mentioned anything about a heat shield either. For what it's worth.
 

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Discussion Starter #8
Yeah, I really wasn't working too hard on it when I first took it off and realized it wouldn't bolt right up. But, over the last few days, I've been thinking about some of the fishing holes and places I would be driving on the rare occasion and there's usually pretty tall, dry grasses. After looking at it again, I figured it shouldn't be difficult at all to make the old one work.
 

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Discussion Starter #9
OK, this morning, I went out and started removing the remainder of the exhaust system. I'd been spraying PB Blaster on the nuts/bolts on the Y-Pope/Manifold for the past week or so in preparation for removal. I HIGHLY RECOMMEND THIS!!!! It will definitely save you a lot of heartache and discontent from having to get out the broken bolts. For the Record, these are 5/8" standard nuts. I used a deep well socket on a breaker bar to begin loosening and then finished with a ratchet, then by hand. Easy, clean and simple. Penetrent and Lube is your friend here.

Special note for those who've worked on older Ford Manifolds/Exhaust systems. There is no need for a secondary O ring spacer gasket. This is a machined type fit metal to metal. I remember helping my Dad fix the exhaust on our 74 Comet and having the wiggle my 10 year old hands down to fit that asbestos, or whatever it was made of, spacers into the downpipe since I was the only one small enough to get into that tight space. No worries here.

If you raise the front of the vehicle to better access the system, please make sure you chock the rear wheels. Here's my special 8900lb Wheel Chocks.
. Also, something I highly recommend is one of these wheel steps. This one's made by HitchMate and holds my 300lbs pretty well.



Make sure you disconnect the O2 Sensor before you disconnect the downpipe. There are no other hangers other than the Air pump hose holding the exhaust up from this area so, if you're going to reuse your original O2 Sensor, you don't want to risk pulling the wires.


After that I went to remove the Air hose for the Thermactor(air pump). This nearly became the bane of my existence.

The angles were to tight to get a screw driver into it and I went through every size of socket I had. Everything was too small or too big. Then, for kicks, I went Metric. FTR: 8mm for the hose clamp and then you can work it off with a screwdriver and some heavy pulling.

Finally, with everything disconnected, you can pull the exhaust out. Or can you? Thank Craftsman for my Sawzall. Nothing would move between the frame and the body. I had to section it out and remove it piece by piece.


Save the Converters and search for a recycler in your area. They pay better than regular scrap for these. It may not be a huge amount but it's better than nothing and it helps offset your purchase of the new system. Mine were still pretty clean considering they're 20 years old.


It'll be a week or two before I will have time again to actually put the new system in. I'll post that up as I go.
 

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Discussion Starter #10
Just for the heck of it. Here's my Exhaust clip. I call it Manifolds Only. It really makes the 300 sound like a whole new Beast.

http://youtu.be/4hGJ2wsQI-Q




I don't know why it's not showing like other YT vids. This is my first vid and first attempt at really putting one up. Anyway, click the link and it'll come up.
 

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It seems to be coming along nicely..... You said that you had a 300 inline 6 in it at one point? Listening to the youtube video it sounds Cessna all the way. I had an F150 with an inline in it and I know it doesn't sound like that in person. Again good job!
 

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Discussion Starter #12
That was kinda of an audiological illusion. I was standing inside the garage when I did that video. Some of that noise was echo. Still not very loud considering it had absolutely no exhaust running on it at all then. I figured I'd add it to the Exhaust clip thread for a laugh.
 

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Discussion Starter #13
What is this part that's on the air tube on the catalytic converter? Maybe a 1 way valve? Is it really something I need to reinstall or get a new one when I install the new system?



Thanks
 

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Yes, that's a one way valve. It definitely needs to be replaced. It allows fresh air to go into the exhaust, but keeps exhaust from coming back out.

I had one go out on my engine and the hot exhaust going the wrong way resulted in a large amount of melted plastic, hoses, vacuum lines, and emissions equipment. It's a good little valve to have in place. =P


However, if your new cat doesn't have the air inlet tube, you can probably remove the whole thing and block off where the air is coming from (the rubber hose at the top).
 

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No, it does. I bought the Walker Cat with the air tube so I could make sure I could keep it as close to factory style Emissions as possible. I want to allow as much opportunity to burn off the excess gasses as possible. I want to be able to have a clean burning well tuned vehicle.
 

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Also if you leave that tube disconnected it sounds like shit.
 

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I sawzall my air tube off the factory y pipe, I think it was welded or pressed into the y pipe. No other way to remove it. Connect it to the new ypipe using a silicone hose. Oh and I painted my new exhaust with black header paint. That was years ago though, and many muddy wheeling adventures later.
 

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I'm going to just Dremel the press fit connector in half and peel the rubber off the tube. As for the painting, I did that with the hanging hardware. I'm not too worried about the rust issue. I don't live in the salt belt and even for the sake of beaches, I live just about geographically in the middle of Florida. No worries about salt spray from the oceans. My strap clamps are all Stainless. the metal tube on the catalytic Converter came off pretty easily. It only took a little banging with a rubber mallet to loosen it up. Hopefully, this next weekend, I'll be able to get everything together and finish the install portion of this thread.

About the only thing I'm seeing as a potential hold back will be this hose for the air tube down to the Catalytic Converter. There's a few different size variations going from the Tube, to the Check Valve, and from the Check valve to the Intake pipe on the Converter. Even the Metal pipe I took off the old converter is about twice the size of the intake pipe for the converter. I'll figure it out though after I get things going. Surprisingly to me, I've really been using my reloading calipers a lot on this project to see what sizes are needed for the different slip and butt joint connections. It's not always as simple as 2 1/2, 2 1/4 , etc on these things.
 

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I'm going to just Dremel the press fit connector in half and peel the rubber off the tube. As for the painting, I did that with the hanging hardware. I'm not too worried about the rust issue. I don't live in the salt belt and even for the sake of beaches, I live just about geographically in the middle of Florida. No worries about salt spray from the oceans. My strap clamps are all Stainless. the metal tube on the catalytic Converter came off pretty easily. It only took a little banging with a rubber mallet to loosen it up. Hopefully, this next weekend, I'll be able to get everything together and finish the install portion of this thread.

About the only thing I'm seeing as a potential hold back will be this hose for the air tube down to the Catalytic Converter. There's a few different size variations going from the Tube, to the Check Valve, and from the Check valve to the Intake pipe on the Converter. Even the Metal pipe I took off the old converter is about twice the size of the intake pipe for the converter. I'll figure it out though after I get things going. Surprisingly to me, I've really been using my reloading calipers a lot on this project to see what sizes are needed for the different slip and butt joint connections. It's not always as simple as 2 1/2, 2 1/4 , etc on these things.
I know what you mean about the size. The size of the tube is bigger than the one on the converter. I haven't been able to get the cap off the tube on the converter yet but it looks like a 1/2" tube will slide over it nicely. I was gonna take a 1/2" tube and cut a slit on the end, then slide it over the cat's tube and hold it down with a hose clamp. Then have the other end welded to some pipe the same size as the air tube. connect them with a length of heater hose and done. as long as my little adapter is long enough the hose shouldn't see too much heat.
 

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Discussion Starter #20
That's my only concern on the converter end of it. I don't have a good single photo of the new Walker converter but the tube on it just comes off about 1-2" and bends 90* parallel with the converter. All the heat will rise up and melt anything but the highest temp stuff around. That's why I was hoping to figure out a way to make that metal pipe from the OEM cats work. Or, figure out some other way to run metal piping up and away before installing teh check valve.
 
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