Exhaust Manifold Question

BzJeep · 05-04-2005, 05:50 PM

Well, we took my Jeep in this past week to figure out why it wasn't starting and they figured out that it was the coil even though it tested fine, so they replaced that and in the process noticed that the exhaust manifold was cracked - they said it was a common problem for the 4.0L and of course they recommended one of their manifolds and said aftermarket ones will just break but that's not my main point right now - what my main point is... is, how involved is removing the manifold on my 93 YJ 4.0L? Can it be removed from the underside of the Jeep? Or will I have to take apart the engine to get to it? I was also wondering if the manifold and the pipe going back to the cat is welded or just clamped on.

Thanks!

75SV1 · 05-06-2005, 07:27 AM

You have to take it off from the top side. The intake and exhaust manifold use the same bolts. There should be a joint for disassembly of the header just at the rear of the engine compartment. You will also have to dismount the Power Steering pump and lay it to one side. So, then you will have to take off the serpentine belt and it helps to take out the Auxilary fan. Might want to get a Chilton or Hayes manual.
Tom

gosupes · 05-06-2005, 07:41 AM

These are stainless stell. Have someone weld your old one. The factory manifolds do crack from what I have heard, but I have one of the "aftermarket" ones and still holding up good.

JeepCrz · 05-06-2005, 11:44 AM

I have broken three exhaust manifolds 2 wranglers and a cherokee. The first good weld seems to hold them.

If your good with a socket set you can do the job yourself. Getting the lower bolts is a real pita from the top.

BzJeep · 05-07-2005, 03:07 PM

Alright, we need to replace the serp. belt anyway and that other stuff shouldn't be too hard to remove I would imagine. I have both manuals so I think all will be good. Do you guys recommend any certain brand of header? I plan on increasing the diameter of my piping from the header back to the cat and replacing the cat aswell during this process so after this, my exhaust should be set!

Thanks guys!

75SV1 · 05-07-2005, 08:34 PM

I went with a Clifford header that is black ceramic coated. I had a Pace Setter that was armour coated on it before. It was OK, but some say the Pace Setters sometimes crack. Mine was good for 3 years and I sold it. Borla has a very good rep as does Banks.
Tom

trequad · 05-08-2005, 01:53 PM

My 94 YJ 4.0 exhaust manifold had a crack and was leaking about a year and a half ago and i had it welded and that only lasted a year.
Guys that i trust at the exhaust shop told me cracking was a very common problem especially where there is temperature extremes during the seasons, so i forked out the cash and bought the Borla Stainless steel header. I had the shop guys put it on and they said everything went smoothly with install and i have absolutely no complaints. If you have the money i think this will give you great results.
Hope this helps.

1-vertical-TJ · 05-18-2005, 01:42 AM

I just finished putting on my new banks torque tube header. That freakin hayes book made me pull my injectors for no reason

(Don't Do That!!) If you have the slightest mechanical mind, a 9/16" deep socket and wrench, 12mm deep socket, and a grinder (my bolts connecting the manifold to the pipe was stubborn so i showed it whos boss). It helps if you have someone else to hold up the intake manifold while you wiggle the new header into place, i had my mom do it

everything went very smooth, oh couple of pointers if you do it yourself,
1 label both ends of all wires connecting to the manifold
2 DONT PULL YOUR INJECTORS, HAYES BOOKS ARE AWFUL!!!!
3 Use an Anti-Sieze thread lube on the manifold bolts
4 There are 11 bolts holding the two manifolds on, 7 on the top, 4 under the exhaust manifold
5 If the Motor Mount gets in the way (if you do this yourself youll know what i mean) ask a friend, brother, father, and yes even your mother to tilt it up and to the rear of the vehicle.
6 Just take your time it gives you a huge sense of accomplishment

75SV1 · 05-18-2005, 06:44 AM

I put on the header first. The two end studs are only used by the header, so they keep it in place, plus the middle bolt or stud (depends on year). Then I put on the intake manifold. I put two of the top bolts with the step washers to keep it in place and then put in the rest. I just did that a few weeks ago, so it fresh in my mind. I still have to shorten one bolt so it will go in. The header bends tight.
Tom

RockPaws · 05-18-2005, 05:13 PM

I recomend using the Banks Torque Tube Header, it carries a life time warranty. Beats paying for it again if it cracks. Banks cracks the least of them all from what I hear. I have replaced a number of cracked headers on customers vehicles. On one ZJ, their on the third manifold due to cracking. They wanted a factory manifold again??

If your engine has many miles on it. I do recomend replacing all the O-rings for the injectors. Yes this means removing the fuel rail. It also makes it easer to install the bolts with it out of the way. While the injectors are removed and the intake manifild is off. Clean it. I usually find the area below the injectors very dirty on high mileage engines. Some times its easer to just remove the sensors and throttle body and take it to your local machine shop and have them run it thru the cleaning tank.
When installing the o-rings I lubricate them with lightly with silicone grease or oil. Makes installing the rail assy a snap.
Always check for fuel leaks when your finished.
The FSM also tells you to remove the fuel rail.
You will also need a torque wrench. Torque is about 24 lb-ft. (check the manual)

RAYMAN975 · 11-26-2005, 11:50 AM

i have a 89 yj with the 4.2 and manual tranny. i know i have an exhaust leak, but not sure where, i know its coming from the engine bay, or the egr 3/4" pipe. but i ordered a "manifold" not header, from 1aautomotive.com, and will get it soon. i figured i might as well replace the manifold while i have the carb off since im doing a mc2100 swap. im also reaplcing the intake/exhaust gasket, and the donut gasket from the manifold to the downpipe. this manifold that i ordered was 60shipped, and it says its a higher quality than stock, and redisigned to not crack. but for 60 bucks, if it ends up being a POS, then im not out much money...

so, my question is, are the 258 manifolds known to crack? or is it just the 4.0L manifolds/headers that are known for that?

05-08-2005, 01:53 PM	#7
trequad Registered User Join Date: May 2005 Posts: 2 Profile Gallery Classifieds My Jeeps	go with the Borla SS header My 94 YJ 4.0 exhaust manifold had a crack and was leaking about a year and a half ago and i had it welded and that only lasted a year. Guys that i trust at the exhaust shop told me cracking was a very common problem especially where there is temperature extremes during the seasons, so i forked out the cash and bought the Borla Stainless steel header. I had the shop guys put it on and they said everything went smoothly with install and i have absolutely no complaints. If you have the money i think this will give you great results. Hope this helps.

05-18-2005, 01:42 AM	#8
1-vertical-TJ Registered User Join Date: Apr 2005 Location: Pontiac, Michigan Posts: 122 Profile Gallery Classifieds My Jeeps	I just finished putting on my new banks torque tube header. That freakin hayes book made me pull my injectors for no reason (Don't Do That!!) If you have the slightest mechanical mind, a 9/16" deep socket and wrench, 12mm deep socket, and a grinder (my bolts connecting the manifold to the pipe was stubborn so i showed it whos boss). It helps if you have someone else to hold up the intake manifold while you wiggle the new header into place, i had my mom do it everything went very smooth, oh couple of pointers if you do it yourself, 1 label both ends of all wires connecting to the manifold 2 DONT PULL YOUR INJECTORS, HAYES BOOKS ARE AWFUL!!!! 3 Use an Anti-Sieze thread lube on the manifold bolts 4 There are 11 bolts holding the two manifolds on, 7 on the top, 4 under the exhaust manifold 5 If the Motor Mount gets in the way (if you do this yourself youll know what i mean) ask a friend, brother, father, and yes even your mother to tilt it up and to the rear of the vehicle. 6 Just take your time it gives you a huge sense of accomplishment __________________ [COLOR=Teal]1997 TJ Sport[/COLOR] 4.0 IL6 5 speed 3.5" Rancho SuperFlex Rockcrawler suspension rsx9000x all around, 33x12.50r15 BFG MT's on 15x8 black steelies, Banks header [URL=http://www.cardomain.com/ride/846871]http://www.cardomain.com/ride/846871[/URL]

05-18-2005, 05:13 PM	#10
RockPaws Registered User Join Date: Jun 2003 Location: Pahrump, NV Posts: 832 Profile Gallery Classifieds My Jeeps	I recomend using the Banks Torque Tube Header, it carries a life time warranty. Beats paying for it again if it cracks. Banks cracks the least of them all from what I hear. I have replaced a number of cracked headers on customers vehicles. On one ZJ, their on the third manifold due to cracking. They wanted a factory manifold again?? If your engine has many miles on it. I do recomend replacing all the O-rings for the injectors. Yes this means removing the fuel rail. It also makes it easer to install the bolts with it out of the way. While the injectors are removed and the intake manifild is off. Clean it. I usually find the area below the injectors very dirty on high mileage engines. Some times its easer to just remove the sensors and throttle body and take it to your local machine shop and have them run it thru the cleaning tank. When installing the o-rings I lubricate them with lightly with silicone grease or oil. Makes installing the rail assy a snap. Always check for fuel leaks when your finished. The FSM also tells you to remove the fuel rail. You will also need a torque wrench. Torque is about 24 lb-ft. (check the manual) __________________ [FONT=Trebuchet MS]01' Jeep TJ (Jeep #5) 3.5 RE Custom SuperFlex, Raingler, Kilby, Currie, Banks, Borla, American Racing, Custom mods, Always more in the works. [URL=http://www.redrock4x4.com][COLOR=Blue]www.redrock4x4.com Rocks![/COLOR][/URL] [URL=www.needhim.org/][COLOR=Blue]Need Him?[/COLOR][/URL][/FONT] Last edited by RockPaws; 05-18-2005 at 05:35 PM..

05-06-2005, 07:27 AM	#2
75SV1 Registered User Join Date: Sep 2003 Posts: 976 Profile Gallery Classifieds My Jeeps	You have to take it off from the top side. The intake and exhaust manifold use the same bolts. There should be a joint for disassembly of the header just at the rear of the engine compartment. You will also have to dismount the Power Steering pump and lay it to one side. So, then you will have to take off the serpentine belt and it helps to take out the Auxilary fan. Might want to get a Chilton or Hayes manual. Tom

05-07-2005, 08:34 PM	#6
75SV1 Registered User Join Date: Sep 2003 Posts: 976 Profile Gallery Classifieds My Jeeps	I went with a Clifford header that is black ceramic coated. I had a Pace Setter that was armour coated on it before. It was OK, but some say the Pace Setters sometimes crack. Mine was good for 3 years and I sold it. Borla has a very good rep as does Banks. Tom

05-18-2005, 06:44 AM	#9
75SV1 Registered User Join Date: Sep 2003 Posts: 976 Profile Gallery Classifieds My Jeeps	I put on the header first. The two end studs are only used by the header, so they keep it in place, plus the middle bolt or stud (depends on year). Then I put on the intake manifold. I put two of the top bolts with the step washers to keep it in place and then put in the rest. I just did that a few weeks ago, so it fresh in my mind. I still have to shorten one bolt so it will go in. The header bends tight. Tom

11-26-2005, 11:50 AM	#11
RAYMAN975 Registered User Join Date: Jul 2004 Location: NE Ohio Posts: 260 Profile Gallery Classifieds My Jeeps	i have a 89 yj with the 4.2 and manual tranny. i know i have an exhaust leak, but not sure where, i know its coming from the engine bay, or the egr 3/4" pipe. but i ordered a "manifold" not header, from 1aautomotive.com, and will get it soon. i figured i might as well replace the manifold while i have the carb off since im doing a mc2100 swap. im also reaplcing the intake/exhaust gasket, and the donut gasket from the manifold to the downpipe. this manifold that i ordered was 60shipped, and it says its a higher quality than stock, and redisigned to not crack. but for 60 bucks, if it ends up being a POS, then im not out much money... so, my question is, are the 258 manifolds known to crack? or is it just the 4.0L manifolds/headers that are known for that?