2.4/2.7 exhaust manifold replacement - request for how to tips and advice

im about to replace my cracked up cast iron exhaust manifold on my 2.4 engine and wanted to know any advice tips or tricks anyone has about doing this job. also its a regular 2wd truck so im working with only 6" of ground clearance

I already have a replacement upgrade stock steel header for 2002+ engines, 2 new OEM donut gaskets, OEM EGR gasket, and high quality fel-pro exhaust manifold to engine gasket. the air intake duct and stuff is out of the way and I already removed the heat shield and I also presoaked all the bolts and it will soak overnight until I do the job tomorrow.

I cant find any youtube videos of this job being done or anything involving removing it so I was hoping for some experienced advice the most efficient way to do it right the first time to avoid busted knuckles and excessive cursing . even simple easy jobs sometimes present issues getting gaskets placed correctly and sealed properly.

thanks in advance for any tips or advice you can share

 

as long as the nuts aren't seized on and they come off its pretty straight forward. Mine has about 300k on it and it came apart good. Just soak them good and if any are iffy comin off spray them again and work them, loosin them a bit then go back the other way workin them a little farther off each time. If that doesn't work try adding some heat. My manifold gasket was metal so I just reused it with my header.

 

The toughest part for me is always pulling the EGR tube off the studs that stick out from the manifold. I usually take the nuts off (2 x 12mm) with a ratcheting wrench then pry the EGR tube off the studs with a big screwdriver. It feels like you're prying too hard, but it will eventually flex enough to get the flange off the studs.

When putting it back together, I pry the end of the EGR tube onto the header studs while the nuts are threaded but still loose on the studs that hold the header onto the head. Having that little bit of play makes it easier to get the EGR pipe to pop on there.

Overall, it's a really manageable job.

 

ok this may be a slight problem then, im replacing the manifold with the 2.7 2002+ years factory steel header and its a used one with the heat shield and has all the nuts to attach it, the 3 studs are already in the main connection flange but no nuts for it, but there are no studs in the EGR port so im guessing the studs are missing or more likely, it used bolts instead of studs and nuts for making this connection. my question is then, isn't this supposed to be using "special" grade bolts for all exhaust manifold connections?

I am assuming I cant just use any old regular grade bolt for this connection what with the high heat and rusting concerns. is this thinking correct or not?

I should add that im not a noob at this, I have average to better then average mechanic skills so short of specialized tools and formal training as well as having a shop, I consider myself on par with most mechanics out there working on cars.

I have built 5 engines from the ground up and rebuilt about 6 trannies and all manor or assorted rebuilds and repairs on several dozen motorcycles.

 

I think I remember removing the studs from the manifold once I had it out, and then I reused them in the header. If I recall correctly, a vise and a pretty good amount of heat were required to get those studs out of the old cast manifold.

I don't see why you can't use bolts for that connection though, if you have trouble getting the studs out. I had one of the holes strip on the header where the y-pipe attaches, and I replaced it with a bolt, nut, and a couple of washers + lock washer. It seems to have worked, although it was a bitch getting the nut and bolt tight - really needed one person tightening from the top through the hood and another from underneath. I ended up pulling the header back off, attaching it to the y-pipe with the nut and bolt on the bench, and then putting the whole thing back in at once.

When I swapped my tranny a couple of weeks ago, I pulled the whole thing out as one piece again rather than undo that one bolt.

 

that's great info, thanks

my header was a used pull off part from a parts truck so it already has the factory installed studs in them and they are still in great shape so at least I don't need to try and remove and reinstall those in the replacement header.

I thought headers or any exhaust connection would need better then average grade nuts and bolts so they have the strength not to be effected by the high heat . not sure where I heard it, but I seam to recall being told exhaust manifold nuts and bolts are not regular standard grade hardware.

I don't think I will have much luck trying to undo studs from a factory stock 15 year old manifold so since I have a set of 12mm bolts (head size) that came out of the block for mounting the fuel filter, they fit the EGR flange threads perfectly so I guess i'll try those and if it looks like they start to have a problem with rust, I could pull them out later and replace them with new studs if need be.

has anyone had any problem reusing the manifold to engine nuts? I ran across a recommendation they shouldn't be reused but they often say that with a lot f things that can be reused without any problems so I figured I would ask if anyone ever had an issue from reusing them.

 

OP. I hope you have a flex head 1/4 in ratchet and some flex head 12mm ratcheting wrenches. If not, go buy some. You can get both of those items in the Gearwrench brand for not too much money. Sears has the flexhead ratcheting wrenches for $19.99 and Home Depot has the exact same wrenches branded under the Husky Brand for the same price. You will need these to make your life easier.

Second, liberally spray the shit out of all your fasteners on the manifold and exhaust pipe in front of the cat. Use Liquid Wrench and give it some time to work its magic.

Third, get yourself some long 3/8 extensions if you dont have any.

The easiest way to do this job is to unbolt the exhaust pipe in front of the cat and remove it (the section from the cat to the manifold) - just pull that off and out of your way - that will make your life easier. The EGR tube is a bit of a bitch, but once you have the nuts off and the studs sliding freely, you can unbolt the exhaust manifold and slide the exhaust manifold off and to the side while pulling back on the EGR, this will give it just enough room for the stud to clear the holes and separate the EGR pipe from the manifold.

Your biggest challenge, I think, will be removing crusty studs from the engine block as you are trying to get the manifold off. Dont gorilla it and strip the nut or stud. Use plenty of liquid wrench. I was lucky in that a few of my manifold nuts were rusted to the studs and they came off in one piece - like a bolt. The OEM studs have an e-torx head (E-10?) but if youre going to use an e-torx socket to take them off, make sure its not a cheap Chinese piece of shit (like Craftsman). Get a good, quality e-torx socket and a long breaker bar for those. Otherwise, you will do the '2 nut' method and God help you if you rip the thread off the stud while doing that.

If you just go slow and steady, its actually a pretty easy job. Again, dont be shy with the liquid wrench.

 

ok, I have some long flex connect (wobble) extensions and a deep socket set in 3/8" and I can get about 18"-24" of reach with them, maybe 36" or more if needed by adding in some straight regular extensions.

I do have a flex head ratchet but I don't have any metric ratchet wrenches. the only thing I was thinking that could be trouble is the EGR nuts and getting that connection loose. should I just go ahead and disconnect the other end of the EGR tube from the engine and take it out with the manifold as one?


the header I have looks to be an identical swap for the cast iron one and the block studs look to be in great shape.

why in the world would I need to remove the studs in the block? shouldn't this replacement Toyota factory manifold for 2002 and newer engines slip right onto the original studs? I don't know about this part of it and im not using an aftermarket part, its an OEM Toyota replacement stock manifold

 

no need to remove the studs in the head, the nuts came off mine no problem. Honestly with the mechanical experience you have, changing the manifold should be a piece of cake. If I remember right I just loosened the nuts on the intake side of the egr tube to allow more movement.

 

also i reused my original nuts with no problems.

 

You're right, you dont need to remove the studs. But in my case, the nuts were rusted to the studs so they both came out in one piece. Once I removed the studs, I saw that it was easier to pry the manifold away from he EGR by sliding it to the drivers side.

And yes, I mean the flexheads for the EGR nuts. The extensions will be for the exhaust pipe from under the truck.

 

ok thanks guys,

im assuming I need to have the exhaust pipe hangers loose so I can drop the exhaust away from the header first before I try to separate it from the EGR and engine since the mounting bolts dictate it can only come out in one direction (pulled straight out) without any wiggle room for sliding in or out of the header flange or EGR.

I will be diving into this after lunch so wish me luck.

as we all know its those freakin 5 minute jobs that end up taking days to finish sometimes because something goes wrong lol

 

Be sure to use OEM gaskets. Aftermarket ones just don't last.

 

ok I got a late start so today was just the take down and tomorrow I will reassemble everything but I got it out and it wasn't bad at all and loosening the intake fitting on the EGR tube made it a lot easier that's for sure.

I separated it at the exhaust manifold to manifold to tail pipe connection by simply removing the two 17mm transmission exhaust pipe clamp bracket bolts that hold the manifold tail pipe in place so this allowed the manifold to move out and off the block studs to lift straight up and come right out and I didn't have to mess with the cat flange at all.

the only question I have now is, I bought the fel-pro gasket for the EGR flange and its a heavy duty cardboard like gasket but my original gasket I removed from the EGRT flange was a metal copper gasket and I don't see why the replacement is a regular cardboard like gasket and im worried it wont last.

can anyone enlighten me as to if I should go get the dealer OEM gasket or are they no longer made of metal too?

also im wondering if I could do what everyone knows you shouldn't do and just reuse the old gasket since the bolts were not any more then snug so im thinking there was some "compression" left in it. in the past I have heated (to soften) and reused copper crush gaskets and washers on motorcycles without any leakage and im thinking I could do that here but I never tried it on a car exhaust pipe.

 

i dont remember on the egr gasket, but i reused the original metal manifold gasket because the ones that came with my pacesetter header were garbage. its been a year and a half now and still no leaks. i usually spray a bit of that copper spray gasket stuff on my gaskets just to help seal any imperfections.

 

Reusing the OEM metal gasket is better than using the fel-pro crap.

Going to the dealer to get the OEM one is worth the trouble.

 

ok got it all back together now.

the studs for the EGR came out really easy (shocker ) only had to reverse directions 2 or 3 times on each when it started binding so getting right type of replacement fastener hardware question is a moot point now and I went back with all 100% stock hardware.

the job was so easy to do, I went ahead and used the fel-pro gaskets for the EGR, because upon closer exam after taking it out of the bag, its a bake-a-lite coating over a hard stainless or aluminum plate gasket making a sandwich so that's why it looked like cardboard at first.

I don't doubt OEM gaskets would be better but its $50 for the manifold to head gasket and $23 for the EGR to manifold gasket so I just used the fel-pro gasket I already bought at $18 for the manifold to head gasket and $6 for the EGR to manifold gasket.

for the manifold to tail pipe connection, I used the OEM donut gaskets there because that is the most critical seal in my opinion as well as the hardest one to have to replace later if it fails, plus they were only $15 for both.

just need to take a few test drives and retorque things every day for a few days until it holds true.

I honestly think most of the problems people have with fel-pro gaskets is they don't go back and retorque things as they should. I have been using fel-pro exhaust manifold gaskets for 30 years and NEVER had one leak or blow out on me.

 

I had no problem with the fel-pro manifold to head gasket, but the fel-pro egr gaskets leaked. After replacing them a couple of times, I sprung for the OEM.

 

makes sense

those nuts are a bitch to get back on, they were not cross threaded but were tight the whole way so I hope they don't leak. if it does, i'll spring for the $25 OEM gasket

I don't waste money on ratchet wrenches anymore because they never have clearance for most bolts in tight places where you actually need them so whats the point, but I will go buy a 12mm one if I have to replace that EGR gasket again because there wont be any clearance issues using one on there and its better fit in that tight space then a flex ratchet

I was all set to reuse the old OEM copper gasket but noticed I galled it with the screwdriver when I was separating the pipe from the manifold, oh well I hope I get lucky and the fel-pro EGR gasket lasts several years.

now while its all apart, I might as well pull the TB and clean that up as well as the IAC