Well, for this write up, I think it might be a good idea to address a few issues with headers....
1. You're likely to crack yours if it's cheaply made, so I wouldn't suggest skimping on the price
2. You're likely to crack it anyways, so make sure it's got a warranty
3. Exhausts that do not have sufficent support, ie. worn out hangars/few hangars/no hangars.....will lead to a cracked header
4. Your stock exhaust manifold blows, so replace it!
So now that thats out of the way, I purchased a Doug Thorley header a few years back and decided to go cheap and just get the chromed steel one. Well, that lasted a while, but with constant heating and cooling of the header, it eventually cracked at the collector. Got it replaced by the warranty and the warrantied one cracked about 6 months later. So I call Jardiene (the company who sells Doug Thorley products) and they informed me that they have stopped making the chromed steel ones because of so many cracked header issues and they only sell the ceramic style now. Now that the header came in, I figure it might be a good time to spread the wealth of knowledge and show how easy it is to do this swap. So here it goes.
Tools you will need:
3/8-24 die
3/8-16 tap
can of compressed air or an air compressor that has an air nozzel adapter
Fuel line quick disconnect wrench
9/16 stubby wrench
9/16 standard wrench
9/16 dogbone
14mm wrench
13mm wrench
ratchet of whatever drive your sockets are
9/16 socket
15mm socket
tools to remove air box (I didn't have one)
flat head screw driver
tools to remove the exhaust from the collector
whatever else you run into because I can't remember anything else....
Well, you're probably thinking this is a crazy hard swap and you can't do it.....NOT SO! All you have to do is remove the left side of the engine, remove the exhaust manifold, install header and reinstall the left side of the engine! Super easy! Well, honestly, here's what we have to do...
1. The first step is to lay out all the parts that you have. Make sure you have them all and they are for the right motor and the right year. It would not be so fun to be halfway through and need to get parts and not have a vehicle. So, in preperation, you might consider this.....buy new bolts, new washers, and new nuts so that you can replace the rusted ones or any you break. Get a tap and die to clean the threads of the studs and chase the threads on the head and block and intake manifold. Get a new intake/exhaust gasket. Its one peice and will save you from future leaks. Get the right sized doughnut coupling for the collector so that you wont have leaks there. Get thread lock and a torque stripe material. So now that you have everything you need, go find your tools and your FSM and lets get started.
2. The next step is going to be removing all electrical connectors from the fuel rail and the various sensors on the drivers side of the engine as well as the throttle and tranny cables (and speed control cable if you're equiped) from the throttle body. When you do this, if you're unsure if you will remember where they all go, lable them by using masking tape on both sides of the connectors and labling them so you remember where they go. Since I know my way around this motor, I don't do that. Its pretty easy to remember where they go by how the wires natually sit, but if you're not positive, its good to make sure they're labled now. It also doesn't hurt to take a picture of the motor so you have a visual reference of how things go. Remember to remove them all off the fuel rail, the throttle body, the O2 sensor, the knock sensor (if you have one), the sensor on the bell housing, and the thermostat. That should be it for electrical stuff. Throw all the wires to the other side of the motor. Remove the bracket that holds the trottle body cables and set that aside as well.
3. The next step is to go ahead and remove the intake that you have as well as the heat shield or air box so that you have room to place the power steering pump and some elbow room. I thought you could get by the first time I did it and found out that it helps out so much and only takes a few minutes more.
4. Remove the vaccume lines from the intake manifold and be careful not to crack them. Also remove the hose from the break booster and the valve cover vents. The brake booster line is helpful in keeping all the lines out of the way.
5. Next is to remove the fuel lines from the fuel rail. Your exact set up will change depending on what year your jeep is. This is a 1999 motor, so there is only one fuel line and it is the supply line. Disconnecting the line from the rail will require a fuel line disconnect wrench and a bit of talent. Remember to bleed the pressure out of the lines before you disconnect them or you might end up with a gasoline shower. On newer rails, this is done by the shrader valve between the number two and three injectors. A flat head screw driver on the valve will do this pretty quick. Make sure you put a rag over the valve when you do this so you don't get gas in your eyes.
Now that everything is off of the maifolds, it should look similar to this
6. Next is to remove the power steering pump and the bracket assoicated with it and the idler pully. Loosen the drive belt and remove it from the pump. Loosen the bolts from behind the power steering pump pully that secure it to the intake manifold. Remove these bolts as well as the bolts for the support bracket. Once all the bolts are removed, place the pump and bracket where the stock air box would normally go, so its out of the way and you don't have to disconnect it.
1. You're likely to crack yours if it's cheaply made, so I wouldn't suggest skimping on the price
2. You're likely to crack it anyways, so make sure it's got a warranty
3. Exhausts that do not have sufficent support, ie. worn out hangars/few hangars/no hangars.....will lead to a cracked header
4. Your stock exhaust manifold blows, so replace it!
So now that thats out of the way, I purchased a Doug Thorley header a few years back and decided to go cheap and just get the chromed steel one. Well, that lasted a while, but with constant heating and cooling of the header, it eventually cracked at the collector. Got it replaced by the warranty and the warrantied one cracked about 6 months later. So I call Jardiene (the company who sells Doug Thorley products) and they informed me that they have stopped making the chromed steel ones because of so many cracked header issues and they only sell the ceramic style now. Now that the header came in, I figure it might be a good time to spread the wealth of knowledge and show how easy it is to do this swap. So here it goes.
Tools you will need:
3/8-24 die
3/8-16 tap
can of compressed air or an air compressor that has an air nozzel adapter
Fuel line quick disconnect wrench
9/16 stubby wrench
9/16 standard wrench
9/16 dogbone
14mm wrench
13mm wrench
ratchet of whatever drive your sockets are
9/16 socket
15mm socket
tools to remove air box (I didn't have one)
flat head screw driver
tools to remove the exhaust from the collector
whatever else you run into because I can't remember anything else....
Well, you're probably thinking this is a crazy hard swap and you can't do it.....NOT SO! All you have to do is remove the left side of the engine, remove the exhaust manifold, install header and reinstall the left side of the engine! Super easy! Well, honestly, here's what we have to do...
1. The first step is to lay out all the parts that you have. Make sure you have them all and they are for the right motor and the right year. It would not be so fun to be halfway through and need to get parts and not have a vehicle. So, in preperation, you might consider this.....buy new bolts, new washers, and new nuts so that you can replace the rusted ones or any you break. Get a tap and die to clean the threads of the studs and chase the threads on the head and block and intake manifold. Get a new intake/exhaust gasket. Its one peice and will save you from future leaks. Get the right sized doughnut coupling for the collector so that you wont have leaks there. Get thread lock and a torque stripe material. So now that you have everything you need, go find your tools and your FSM and lets get started.
2. The next step is going to be removing all electrical connectors from the fuel rail and the various sensors on the drivers side of the engine as well as the throttle and tranny cables (and speed control cable if you're equiped) from the throttle body. When you do this, if you're unsure if you will remember where they all go, lable them by using masking tape on both sides of the connectors and labling them so you remember where they go. Since I know my way around this motor, I don't do that. Its pretty easy to remember where they go by how the wires natually sit, but if you're not positive, its good to make sure they're labled now. It also doesn't hurt to take a picture of the motor so you have a visual reference of how things go. Remember to remove them all off the fuel rail, the throttle body, the O2 sensor, the knock sensor (if you have one), the sensor on the bell housing, and the thermostat. That should be it for electrical stuff. Throw all the wires to the other side of the motor. Remove the bracket that holds the trottle body cables and set that aside as well.
3. The next step is to go ahead and remove the intake that you have as well as the heat shield or air box so that you have room to place the power steering pump and some elbow room. I thought you could get by the first time I did it and found out that it helps out so much and only takes a few minutes more.
4. Remove the vaccume lines from the intake manifold and be careful not to crack them. Also remove the hose from the break booster and the valve cover vents. The brake booster line is helpful in keeping all the lines out of the way.
5. Next is to remove the fuel lines from the fuel rail. Your exact set up will change depending on what year your jeep is. This is a 1999 motor, so there is only one fuel line and it is the supply line. Disconnecting the line from the rail will require a fuel line disconnect wrench and a bit of talent. Remember to bleed the pressure out of the lines before you disconnect them or you might end up with a gasoline shower. On newer rails, this is done by the shrader valve between the number two and three injectors. A flat head screw driver on the valve will do this pretty quick. Make sure you put a rag over the valve when you do this so you don't get gas in your eyes.
Now that everything is off of the maifolds, it should look similar to this
6. Next is to remove the power steering pump and the bracket assoicated with it and the idler pully. Loosen the drive belt and remove it from the pump. Loosen the bolts from behind the power steering pump pully that secure it to the intake manifold. Remove these bolts as well as the bolts for the support bracket. Once all the bolts are removed, place the pump and bracket where the stock air box would normally go, so its out of the way and you don't have to disconnect it.
