masospaghetti
Explorer Addict
- Joined
- October 22, 2006
- Messages
- 1,526
- Reaction score
- 160
- City, State
- Huntington Beach, CA
- Year, Model & Trim Level
- 98 XLT, OHV, 4D, 4x4, 5M
I am in the process of installing my passenger side exhaust manifold and thought i'd share a couple things I learned along the way.
1 - Early 5.0 steel "tubular" manifolds are still available, but the cast-type manifolds used on later years do fit, and are a lot cheaper. They also look like they will flow a little bit better. Advance auto has the cast type, Dorman brand, for about $70 (which means you can get them for less than $50 with their coupon codes). Part # 674-329 (passenger) and 674-334 (driver).
Here is a comparison between the cast and tubular style manifolds (this one is the driver's side):
2 - Attaching hardware to the head are 3/8-16 bolts, 1" long. Any hardware store will have them. With the cast manifolds, one bolt goes through a thicker section of the casting and therefore needs a longer bolt. I used a 2.5" bolt.
Mcmaster is a great source of high quality hardware. You can get a box of 25 bolts for $10 - enough to do both manifolds (just have to get one of the longer bolts separate). http://www.mcmaster.com/#standard-cap-screws/=p6l7ew
3 - The driver's side dipstick will have to rotate a bit to clear the cast manifolds. I had to cut off the mounting tab. I currently am using a worm-type hose clamp to keep the dipstick tube from moving around but will eventually weld on a new tab.
4 - My driver's side manifold had a 3" long crack at cylinder #1 hidden by the heat shield. My passenger side manifold was cracked about 90% through between cylinders #2 and #3 .
Here is my cracked driver's side manifold:
Here is my severed passenger side manifold:
5 - The passenger side tubular style manifold cannot be removed in one piece with the air conditioning plumbing intact. I broke mine in two to remove it. The cast manifold is smaller and can be installed without much issue. Also to note, Haynes manuals' say that you have to remove the a/c pump to take out the driver's side manifold, and this is plainly not true. You can remove the single bolt holding the steering shaft together and move it out of the way to get enough room.
Here is the new cast manifold installed, this gives you an idea how much room there is to work:
6 - The inner bolt between the passenger side manifold and the collector was difficult to get to. I used freeze-off lubricant, 15mm deep impact socket, impact swivel, and a couple extensions and I could get to it from underneath. There was a little "peg" that I had to hacksaw off the pipe to get access. I don't see how there's any other way to get this bolt off. A good 5 minutes with an impact wrench pulled it loose.
Here is the two extensions and swivel I used, its hard to see because they are obviously impact black. The "peg" I had to cut off was where the swivel is in this picture:
7 - The replacement passenger side manifolds all have the EGR port built into it. Since my 5.0 is an early build with the "internal" EGR, I didn't need this port. I believe a M22-1.5 plug will fill the hole. It's not a common size but it does seem to be available online from a few different sources. Alternatively, Dorman provides a fitting already installed in the manifold to allow hookup to an external EGR pipe. Thus fitting could be tapped with a 3/8 NPT pipe tap and plugged this way.
Many thanks to other members here, I wouldn't have gotten this far without ya'll!
As koda2000 mentions below, definitely use a high-temp anti-sieze on all bolts and grade 8 hardware. Grade 8 bolts in these sizes are about $0.50 each - don't skimp out.
1 - Early 5.0 steel "tubular" manifolds are still available, but the cast-type manifolds used on later years do fit, and are a lot cheaper. They also look like they will flow a little bit better. Advance auto has the cast type, Dorman brand, for about $70 (which means you can get them for less than $50 with their coupon codes). Part # 674-329 (passenger) and 674-334 (driver).
Here is a comparison between the cast and tubular style manifolds (this one is the driver's side):
2 - Attaching hardware to the head are 3/8-16 bolts, 1" long. Any hardware store will have them. With the cast manifolds, one bolt goes through a thicker section of the casting and therefore needs a longer bolt. I used a 2.5" bolt.
Mcmaster is a great source of high quality hardware. You can get a box of 25 bolts for $10 - enough to do both manifolds (just have to get one of the longer bolts separate). http://www.mcmaster.com/#standard-cap-screws/=p6l7ew
3 - The driver's side dipstick will have to rotate a bit to clear the cast manifolds. I had to cut off the mounting tab. I currently am using a worm-type hose clamp to keep the dipstick tube from moving around but will eventually weld on a new tab.
4 - My driver's side manifold had a 3" long crack at cylinder #1 hidden by the heat shield. My passenger side manifold was cracked about 90% through between cylinders #2 and #3 .
Here is my cracked driver's side manifold:
Here is my severed passenger side manifold:
5 - The passenger side tubular style manifold cannot be removed in one piece with the air conditioning plumbing intact. I broke mine in two to remove it. The cast manifold is smaller and can be installed without much issue. Also to note, Haynes manuals' say that you have to remove the a/c pump to take out the driver's side manifold, and this is plainly not true. You can remove the single bolt holding the steering shaft together and move it out of the way to get enough room.
Here is the new cast manifold installed, this gives you an idea how much room there is to work:
6 - The inner bolt between the passenger side manifold and the collector was difficult to get to. I used freeze-off lubricant, 15mm deep impact socket, impact swivel, and a couple extensions and I could get to it from underneath. There was a little "peg" that I had to hacksaw off the pipe to get access. I don't see how there's any other way to get this bolt off. A good 5 minutes with an impact wrench pulled it loose.
Here is the two extensions and swivel I used, its hard to see because they are obviously impact black. The "peg" I had to cut off was where the swivel is in this picture:
7 - The replacement passenger side manifolds all have the EGR port built into it. Since my 5.0 is an early build with the "internal" EGR, I didn't need this port. I believe a M22-1.5 plug will fill the hole. It's not a common size but it does seem to be available online from a few different sources. Alternatively, Dorman provides a fitting already installed in the manifold to allow hookup to an external EGR pipe. Thus fitting could be tapped with a 3/8 NPT pipe tap and plugged this way.
Many thanks to other members here, I wouldn't have gotten this far without ya'll!
As koda2000 mentions below, definitely use a high-temp anti-sieze on all bolts and grade 8 hardware. Grade 8 bolts in these sizes are about $0.50 each - don't skimp out.