I'm hearing exhaust noise from the driver's side when my engine is cold, but after the engine warms up, the noise goes away. All of my collector bolts/muffler clamps are tight. The riser swings freely, and seems to be functioning normally, but I think I may have a leak. Has anybody had this issue before, and can suggest a fix?
I would suggest seeking out the leak when it is cold and making remedy decisions based on your findings. Have you tried snugging up all the fasteners?
The 430 manifold is very thin on the inside and is prone to hairline cracks. Especially on the L side. Probably where your leak is.
Just got the vehicle back from the shop: I asked them to inspect the exhaust manifold for any cracks and/or leaks. They found no damage to the manifold, but the riser assembly was loose and rattling when cold. I have a call in to get a replacement heat riser. So: good news. Looks like I won't need to replace the manifold.
My new heat riser from Hamilton Manufacturing has arrived. However, the part was not shipped with any packing material in the box, and the bi-metal coil & retaining clip got busted off. I think I can probably re-assemble it, and hopefully it should function as intended. How tight do I need to wind the coil? Do I just wind it minimally tight to close the valve?
My new valve has no play in the shaft, and opens/closes smoothly. However, the valve was shipped fully assembled, and it arrived disassembled. I hope the bi-metal coil isn't broken...the inner tab is really short.
