The heat riser is a valve that closes the exhaust on the cylinders of V8 engines especially during cold or humid days. This operation is essential in preventing the engine from getting cold. The valve channels hot gases from the exhaust to the intake manifold and out to the exhaust manifold. As long as the gases are kept from freezing, the engine will work properly without stalling. When the heat riser is damaged or inefficient, it should be replaced in favor or a new one.
Tools and Materials
- Ratchet Wrench and Socket Set
- Car Jack
- Jack Stand
- New Heat Riser
Step 1 – Disassemble the Headers
Detach the negative battery cable and raise the vehicle using a car jack. Be familiar with the jack joints of the car before lifting it up. Place a jack stand underneath the car for support. If the car is equipped with oxygen sensor, disconnect it. Loosen the bolts on the stock exhaust pipes from the manifolds.
Detach the old heat riser in between the header collector and the Y-pipe assembly by loosening the mounting hardware securing it in place. Refer to the manufacturer’s manual for a guide on how the riser is mounted onto the pipe and header collector since this has many variations.
Detach the hot and cold air tube if they are equipped and detach the air cleaner assembly as well. Detach the spark plug wires and move them out of the way. Locate the dipstick tube retainer bracket in the valve cover bolt and remove it. Unbolt the manifolds and remove them. While you are at it, clean the gasket on the exhaust flange on the cylinder.
Step 2 – Install the Heat Riser
Purchase new heat riser and begin the installation. If the car uses an early style heat riser that does not have a tapered flange to seal, purchase a newer model that is compatible with the car’s engine. Replace the flange gaskets and headers in their original position. Secure the washers and bolts carefully. Make sure that the pieces are in proper alignment. Reconnect the spark plug wires and the retainer bracket of the dipstick tube.
Reconnect the air cleaner assembly as well as the hot and cold air tubes using the proper adapters provided. As soon as the above procedures are completed, connect the new heat riser in between the header collector and the Y-pipe assembly. The device should come with its own flat gasket, hex bolts, flat washers and lock washers. Check the manufacturer’s manual on the correct configuration of the device and the variations in which it can be installed. Tighten the washers and bolts but never over-tighten.
Step 3 – Inspect the Installation
Ensure that the headers are installed properly with the correct clearance. Before reconnecting the negative battery cable, check to make sure that nothing has been missed. Remove the jack stand carefully. Start the car and inspect for leaks. Turn off the engine, let it cool, and double check the bolts on the flange. Tighten them if necessary.