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Corroded exhaust header flanges on 16v Sun Mar 08, 2020 1:17 pm
stanthomas
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I've pulled the exhaust off my '91 K100RS 16V.
As you can see in the pic, the flanges are badly corroded. Looks like flanges are permanently attached to the pipes on 16Vs. My plan now is to grind the rust away and either weld the flanges to the pipe or make up collets to hold the flange against the lip on the end of the pipe. I'd be grateful for some information about what they were like when new. Should the flanges 'float' on the pipe so they can be aligned with the studs or were they originally welded up solid? And are they just that bit of flat 5mm plate or did they incorporate a sleeve that's rusted onto the pipe on mine?
![Corroded exhaust header flanges on 16v Y4m556byVNAifVIjTdOhE-T2hl3vskEdiq2HYAbnZcNhVYhIjSEouUWaPT9ZbJfXrt3X9LJT6iPhWqp7yPMqhHzkRdMuYG8GBZqaiWctO6uaW86PPV9IHAnp1sJEbpRP3B2lBj-MB8MHFUj0jFhNs-Wok85nqiLruEaDZ9rIV7aexKm_dc_O8Vu0CY0-bm7-W_JsbGPEZFDD5ruRgKluZ61PA?width=576&height=1024&cropmode=none](https://dehnha.db.files.1drv.com/y4m556byVNAifVIjTdOhE-T2hl3vskEdiq2HYAbnZcNhVYhIjSEouUWaPT9ZbJfXrt3X9LJT6iPhWqp7yPMqhHzkRdMuYG8GBZqaiWctO6uaW86PPV9IHAnp1sJEbpRP3B2lBj-MB8MHFUj0jFhNs-Wok85nqiLruEaDZ9rIV7aexKm_dc_O8Vu0CY0-bm7-W_JsbGPEZFDD5ruRgKluZ61PA?width=576&height=1024&cropmode=none)
All the nuts were rusted on so the studs have come out. (and been thrown in the bin). As you can see in this pic, one stud on #2 brought an insert out with it. Looks a little diffrent from your run-of-the-mill helicoil. Do all the studs holes in the head have inserts or is this a repair?
![Corroded exhaust header flanges on 16v Y4mAvIPNdZyS4yad5r0t5jElzxWlBLXPpwQhDgT0qBdZgBlKFPOGx8WsmnZzdSKnsE_mdyxThMr4xyb3DT__9OkywzOIN_fpHTAof68QFI4EWG1haji0VnwCjs1S186D2Gp95qtOVVENc8c-nMJuERCTxk_cfc3py-HcxLQpzY_F6cTYb45DxZyHDeCHW_dMcT8ziwS7QAYO49uqrnekUCsaA?width=1024&height=575&cropmode=none](https://c0hfha.db.files.1drv.com/y4mAvIPNdZyS4yad5r0t5jElzxWlBLXPpwQhDgT0qBdZgBlKFPOGx8WsmnZzdSKnsE_mdyxThMr4xyb3DT__9OkywzOIN_fpHTAof68QFI4EWG1haji0VnwCjs1S186D2Gp95qtOVVENc8c-nMJuERCTxk_cfc3py-HcxLQpzY_F6cTYb45DxZyHDeCHW_dMcT8ziwS7QAYO49uqrnekUCsaA?width=1024&height=575&cropmode=none)
As you can see in the pic, the flanges are badly corroded. Looks like flanges are permanently attached to the pipes on 16Vs. My plan now is to grind the rust away and either weld the flanges to the pipe or make up collets to hold the flange against the lip on the end of the pipe. I'd be grateful for some information about what they were like when new. Should the flanges 'float' on the pipe so they can be aligned with the studs or were they originally welded up solid? And are they just that bit of flat 5mm plate or did they incorporate a sleeve that's rusted onto the pipe on mine?
All the nuts were rusted on so the studs have come out. (and been thrown in the bin). As you can see in this pic, one stud on #2 brought an insert out with it. Looks a little diffrent from your run-of-the-mill helicoil. Do all the studs holes in the head have inserts or is this a repair?