https://www.boltdepot.com/fastener-information/materials-and-grades/thread-galling.aspx
Tester
I had to replace a muffler on my 1978 Oldsmobile Cutlass. I bought a muffler at NAPA and spent two hours removing the old muffler and installing the new muffler. Several years later, the muffler needed to be replaced again. I went to an independent muffler and exhaust shop. A new muffler was installed in less than 10 minutes for less money than I paid for the muffler at NAPA. Since that time, I take all exhaust work to this shop.
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Yeah same thing. My 86 park ave had the muffler way in back by the bumper. The car was driven two miles to school and two miles back home again, so it never warmed the muffler up enough to dry it out. About ever two years Iād need a muffler. Did the first one myself. Second one took it to a muffler shop a relative owned for a lifetime muffler. When I went back again I actually paid for a new muffler when he said the lifetime muffler was the same muffler as standard. He didnāt charge for the ten minutes labor though. All my mufflers are stainless now though and havenāt bought one for a long time. Donāt even know where I would go since relative died and shop closed.
I already did the research on the best penetrating oil for another project. It seems to be liquid wrench.
Not sure about using stainless, like people said galling would occur.
I was just going to use 10.9 grade bolts that I see listed for exhausts for this car online in online retailers. I was just going to copy the torque values in the service manual.
Iāve got a can of liquid wrench that I bet I havenāt touched in 20 years. Might as well pour a can of coke on it. Pb blaster is what I reach for but there are better ones too.
Doesnāt look like you or John Smith will be getting a free exhaust system repair while drinking coffee.
Ten years ago, I paid $40 for a muffler for my truck, no repair shop can match that price for an installed muffler. I donāt believe the comments saying they can replace the exhaust system for less than the cost of the parts.
Yeah gee I donāt even have that 1986 Buick anymore so no need of a muffler shop.
pblaster for me!
Like using aluminized pipe and regular welding wire instead of stainless so that itās rusted out again in a few years and you have to come back? What about getting rid of the flanges so if you have to take the gas tank down you have to cut the pipe in two places instead of unbolting the flanges?
Make sure the shop actually does a good job!
What about using anti seize on stainless bolts or using brass nuts on stainless bolts to prevent galling?
Failing engine mounts can cause a flex joint to fail early.
I tried to paint the flanges on an exhaust pipe next to the catalytic converter using the exhaust manifold paint, which is the highest temperature of the three high temperature spray paints at the auto parts store. That was a big failure. I donāt know if the paint is junk, or I didnāt prep it properly, or if the curing proceduce wasnāt done correctly. It probably didnāt get hot enough to cure properly.
Also wondering about painting it to prevent rust. Which brand did you use that didnāt work for you?
I guess for some the journey is better than arriving at the destination.
Painting the exhaust in a 18 year 200000 mile vehicle is silly.
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So is stainless bolts and anti seize. Rusting prevents them from coming loose and rattles. When the rust you cut them off.
Pretty sure my rear pipe flex is leaking. I have v6 so front and rear pipes. These arenāt too bad. $140. The flanges at both ends might not be hard to separate.
VHT FlameProof Coating: Flat Black, Aerosol, Ceramic Resins Resist Heat Up To 2000 Deg. F, 11 Oz
It requires a rather high temperature curing process. I probably didnāt to it properly. I should have used 500F not 2000F for the exhaust system except the manifold and the pipe directly from it which may need the 2000F stuff.
Painting an exhaust system is like putting lipstick on a pig.
Why?
Tester
3 Likes
Yep, buy the parts, put them on, done.
What do you think you did wrong? I saw POR15 makes high temp paint, but that only goes to 1200F. But that wouldnāt work?
Would painting it help prevent it from rusting, if you install a brand new one that is painted.
Your car, do what you want, spend as much money on the exhaust system as you want.
Lipstick on a pigā2005 grocery getter with 200K miles!
It is not a show vehicle with visible exhaust system like a bucket T hot rod.
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I think that coating is for exhaust manifolds, not the cat-back portion.