Exhaust doughnut (454)

Nov 28, 2020
While on trip in RV (Fleetwood Southwind Storm) I had my passenger-side exhaust doughnut blow while going down the 405 approaching Seal Beach, Ca. Crawled under the following morning and sure enough the only thing left was the metal ring. Soaked everything down with PB (both sides of exhaust at the flange. And bought (2) new Fel-pro doughnuts.

Wanted to purchse the nuts and springs and (2) different places did not have them in stock. Can't wait as I now have to high tail it home (Renton, Wa.) Get it all back together and roll on home ~ 1330 miles. Shortly before reaching home (Tacoma - Federal Way area) I hear the exhaust again. Got home and the next day...sure enough the passenger side doughnut is 90-95 percent gone.

While underneath I grab the springs andway to much play in them. I could literally slide it up/down the exhaust stud (not holding the pipe-flange). Purchase new springs and nuts. Pull the pipe down (both sides). Compared the new springs to old ones and they were at min 1/2in shorter than the new ones. I clean everthing up real well applied a nice coat of copper seize to the stud, nut threads, flange hole and spring ends and put it all back together. When tightening I tighten them equally and with roughly 1/8th-1/16th in gap between the spring coils (not fully collapsed).

Moral here...replace the spring and nuts if you remove the flange for any reason.
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