Exhaust heat riser valve.

jaskispyder said:
the passenger exhaust valve unit... Which side is up? The flat side or the side with the inset area? '73 345. Thanks
Click to expand...

The valve is installed so that it operates correctly....

As the engine heats up, the spring on the valve weakens due to the heat increase and allows the weight of the counterweight to be pulled down by gravity overcoming the spring tension, therefore opening the valve, ie. Turning the internal valve/plate from horizontal to vertical and allowing the full flow of exhaust.

When the engine is shut down and cools off, the valve will close under spring tension as it cools.

Also, there is typically a gasket used with this installation.
 
Yup, I understand how it works. I just slapped it back together so quickly I didn't think to check for proper movement (other than making sure it is free). I ordered a new one as the spring seemed a little weak even after warming up. Better to be safe.
 
If you understand how it works, then you understand how it is installed. Congrats!
 

Attachments

  • Exhaust Regulator Assy. .jpg
    Exhaust Regulator Assy. .jpg
    27.1 KB · Views: 241
Last edited:
Ordered a new riser valve, it is much more solid than my old one... No issues with excess play and "slack" in the bi-metal spring.
 
You must log in or register to reply here.
Back
Top