Header flange broken!
02-23-2019, 02:37 PM
#12
These are definitely cheap SS headers. Supposedly 304 stainless. They've been in the truck for about 4 years and see pretty much daily service. Iive in NJ where the roads get heavily brined and salted at the slightest hint of snow, so they've been exposed to that for 4 winters.
All that said, they show quite a bit of oxidation and pitting, especially on both of the flanges (at the head and collector). This is my first experience with SS headers, but I expected better durability from SS. But, not really sure what's a realistic expectation for this material. In the old days, Blackjack were the cjeap headers. I bought used Blackjack headers and ran then for years - carbon steel with no coating. So I expected pretty long life from SS.
The collector flange weld is what broke. Tubing totally intact, it pulled right out of the flange. I welded the flange back on - MIG welded, after seeing all the rust. I figured if there's that much carbon in there, I could get away with MIG. If there's really 16% nickel in these headers, my weld will undoubtedly fail, but we'll see. It might outlast the pitted tubes.
All that said, they show quite a bit of oxidation and pitting, especially on both of the flanges (at the head and collector). This is my first experience with SS headers, but I expected better durability from SS. But, not really sure what's a realistic expectation for this material. In the old days, Blackjack were the cjeap headers. I bought used Blackjack headers and ran then for years - carbon steel with no coating. So I expected pretty long life from SS.
The collector flange weld is what broke. Tubing totally intact, it pulled right out of the flange. I welded the flange back on - MIG welded, after seeing all the rust. I figured if there's that much carbon in there, I could get away with MIG. If there's really 16% nickel in these headers, my weld will undoubtedly fail, but we'll see. It might outlast the pitted tubes.
To emphasize how long I have had mine, before I posted I went to their website to check what material they use (304), and they are double the price that I paid. Ouch!
02-23-2019, 06:33 PM
#13
On The Tree
Thread Starter
I doubt that they're 304. I imagine that I drive in as much salt as you do, and my 10+ year old Stainless Works headers are only discolored, not pitted or oxidized. They did just start cracking at the tube/flange joints the fall of '17 and spring of last year. I tig'ed them back together adding 304 filler. Because heat anneals work hardened stainless, I am hoping that re-welding them adds a lot of life. I think that your MIG weld, which is probably 70xx series wire, should last the remaining life of your headers, especially if you take care of the motor mounts.
To emphasize how long I have had mine, before I posted I went to their website to check what material they use (304), and they are double the price that I paid. Ouch!
To emphasize how long I have had mine, before I posted I went to their website to check what material they use (304), and they are double the price that I paid. Ouch!
When it's time to replace these, I'll likely go with regular long tube headers. I am now wondering if ceramic coated carbon steel isn't the way ro go.
02-23-2019, 08:06 PM
#14
Thanks for this feedback. I was going to ask what's a reasonable expectation for 304 stainless headers after 4 years of service. You gave me a good idea of the answer in your post. I'll try to post pictures of the header i repaired to illustrate the oxidation. I strongly suspect they're not 304 either. They sure were shiny when they came out of the package!
When it's time to replace these, I'll likely go with regular long tube headers. I am now wondering if ceramic coated carbon steel isn't the way ro go.
When it's time to replace these, I'll likely go with regular long tube headers. I am now wondering if ceramic coated carbon steel isn't the way ro go.
02-28-2019, 10:06 AM
#15
On The Tree
Thread Starter
Here are pics of the header flange at the head, which shows the heavy pitting and corrosion - including the deteriorating welds where the tubes meet the flange.
The other pic shows my wed repair of the flange where it broke. I say it "broke", but what it looked like was that the weld pretty much disintegrated and went away. These headers and their welds were very well prepped and poished when new. They looked extremely pretty. I noted at the time that the welds had all been ground and polished, and remembered from my circle track days that grinding welds on the roll cage was a major no-no. I wondered about the longevity of these welds because of the small amount of filler material and the cosmetic treatment. I figured at the time that since they are 304 stainless, there won't be a corrosion issue, maybe they'll be OK, especually since it's an exhaust header and not a roll cage...
At this point I don't believe these are 300 series stainless at all; and I doubt they're 400 series stainless, either.
03-01-2019, 06:36 PM
#18
On The Tree
Thread Starter
I didn't take a picture of the pitted tubes. The underside of the tubes are pitted - not so badly that I think they'll have holes next week, but more than I expected for stainless.
So, whatever they are, they have a relatively short ife span. And considering that I paid - I forget, around $150, maybe $175 - I guess I shouldn't bitch. Much. I'll go a different direction next time.
So, whatever they are, they have a relatively short ife span. And considering that I paid - I forget, around $150, maybe $175 - I guess I shouldn't bitch. Much. I'll go a different direction next time.
03-12-2019, 02:03 PM
#19
On The Tree
Thread Starter
Today, I was replacing plugs and wires, and needed a magnet to retrieve a dropped spark plug. For kicks, I decided to see how the magnet reaponded to the header tubing and flanges. I was fully prepred for the magnet to sticknto the tubes, especially since I touched it to the tubes near the bends. Some stainless alloys which are non-ferritic can wind up being somewhat ferritic (magnetic) - non "ferrous" vs "non-ferrous", for those of you who think I just made a mistake - as a result of being cold-worked. Like being bent into header tubes. To my surprise, the magnet didn't stick even sightly to the tubes anywhere. So, I guess the tubes must be 300 series stainless, despite how they look after a relatively short time. The flanges, however, are definitely mild steel and NOT stainless. Which is not surprising, considering how they look. Or maybe they're some 400 series stainless, but I highly doubt it based on how rusty and pitted they are.
I wonder if the mild steel vs 300 series stainless welded joint at the collector/ pipe flange joint accounts for that weld pretty much disappearing?
Any of you welders have an answer to this?
I wonder if the mild steel vs 300 series stainless welded joint at the collector/ pipe flange joint accounts for that weld pretty much disappearing?
Any of you welders have an answer to this?
