Mazda never published torque specs for the various fasteners on the MazdaSpeed Protege's turbocharger assembly and therefore I had to reverse engineer this. There is widespread over-torquing of these fasteners and causing them to be damaged in some form as well as improper torque sequencing which has caused exhaust leakage. Since no one has this information or has went through the trouble to get this information, I again took it upon myself to procure and share this information with the community.
I went ahead and took pics of the turbo assembly and visually laid out the torque specs in them.
Torque sequencing numbers are shown in the PDF. It is a two step tightening process. You will need to buy a torque adapter SST to tighten those manifold nuts and bolts properly. Follow the instructions part of the SST to calculate your correction figures to compensate on your torque wrench. You will also need a stud installer to properly install the studs. The torque specs are for FACTORY FASTENERS ONLY. The tightening sequence will take any where from 30 to 60 minutes depending on your skill level/technique/quality of tools you use. There is no other way to properly tighten these parts without causing future problems. Every one of the cars I installed these particular parts on never came back with exhaust leak problems nor fastener problems. DO IT OR REGRET IT!
There are different fastener materials used on the turbo/exhaust manifold assembly. I recommend using the proper anti-seize compound to prevent galling or seizure of the fasteners. DO NOT USE the cheap parts store anti-seize or from any normal retail store. They suck and they don't work for this application!
The following fastener types are used:
-Exhaust manifold bolts with captured lock washer (OEM Mazda Japan): Metric class 8.0, M8x1.25 thread, zinc hexavalent chromium zinc plated (made before 2007, lot # first digit "7") steel or zinc trivalent chromium plated (made on/after 2007, lot # first digit "7", RoHS compliant) steel
-Exhaust manifold studs: Metric class 8.0?, M8x1.25 thread, zinc hexavalent chromium zinc plated (made before 2007, lot # first digit "7") steel or zinc trivalent chromium plated (made on/after 2007, lot # first digit "7", RoHS compliant) steel
-Exhaust manifold interfering thread nut (self locking): Metric class 8.0?, M8x1.25 thread, zinc hexavalent chromium zinc plated (made before 2007, lot # first digit "7") steel or zinc trivalent chromium plated (made on/after 2007, lot # first digit "7", RoHS compliant) steel
-Exhaust manifold to turbo studs and turbo outlet studs: Metric class A2-70?, M8x1.25 thread, 304 stainless steel class 70?
-Exhaust manifold to turbo nuts and turbo outlet interfering thread flange nuts (self locking): Metric class 8.0?, M8x1.25 thread, phosphate plated steel?
-Turbo outlet pipe (aka S-pipe) to exhaust studs: Metric class A2-70?, M10x1.25 thread, 304 stainless steel class 70?
-Turbo outlet pipe (aka S-pipe) to exhaust interfering thread flange nuts (self locking): Metric class A2-70?, M10x1.25 thread, 304 stainless steel class 70?
Due to the fact that different metallurgical types are used on all of the fasteners listed above, you really should use the proper anti-seize compound as I already said.
You will need the following per metallurgical type:
-Stainless steel studs: Nickel anti-seize compound (ie: SAF-T-EZE NPT-.25 or NPBT-8, or Henkel 77124)
-Exhaust manifold bolts and studs INTO head: Copper anti-seize compound (ie: SAF-T-EZE SBT-8C, or Henkel 51147)
-Exhaust manifold nuts to studs: Aluminum graphite anti-seize compound (ie: SAF-T-EZE ST-1, or Henkel 34517)
It is strongly recommended that exhaust fasteners listed above (turbo area/related) be replaced whenever they are removed. If you removed the turbo from the exhaust manifold, for example, then replace all the studs, nuts, and the exhaust manifold bolts. Since the turbo to S-pipe fasteners weren't touched, you can leave them alone. But, if you removed every nut and bolt, then replace everything!
Use of high quality anti-seize compounds will not only make life easier, but there's a possibility of reusing the stainless steel studs (against recommendations) because there's less risk of thread galling. You really get what you pay! The cheap stuff doesn't cut it and only works fine for areas not exposed to high heat. However, due to extreme heat cycling, metallurgical properties of all the fasteners around the turbo changes. They either become too soft or too brittle to provide the correct tensile strength. It is for these reasons why it is recommended that they all get replaced whenever they are removed. If you don't, then there's a great possibility you may run into problems in the near future, such as breakage or one of them falling off. It's just not worth it for the downtime plus having to mill the parts back to trueness again due to warpage!
Due to the hours spent by me reverse engineering these specifications, the pics and information are under copyright. Watermarks and notices have been placed in the PDF to enforce this. Thanks for the understanding.
I went ahead and took pics of the turbo assembly and visually laid out the torque specs in them.
Torque sequencing numbers are shown in the PDF. It is a two step tightening process. You will need to buy a torque adapter SST to tighten those manifold nuts and bolts properly. Follow the instructions part of the SST to calculate your correction figures to compensate on your torque wrench. You will also need a stud installer to properly install the studs. The torque specs are for FACTORY FASTENERS ONLY. The tightening sequence will take any where from 30 to 60 minutes depending on your skill level/technique/quality of tools you use. There is no other way to properly tighten these parts without causing future problems. Every one of the cars I installed these particular parts on never came back with exhaust leak problems nor fastener problems. DO IT OR REGRET IT!
There are different fastener materials used on the turbo/exhaust manifold assembly. I recommend using the proper anti-seize compound to prevent galling or seizure of the fasteners. DO NOT USE the cheap parts store anti-seize or from any normal retail store. They suck and they don't work for this application!
The following fastener types are used:
-Exhaust manifold bolts with captured lock washer (OEM Mazda Japan): Metric class 8.0, M8x1.25 thread, zinc hexavalent chromium zinc plated (made before 2007, lot # first digit "7") steel or zinc trivalent chromium plated (made on/after 2007, lot # first digit "7", RoHS compliant) steel
-Exhaust manifold studs: Metric class 8.0?, M8x1.25 thread, zinc hexavalent chromium zinc plated (made before 2007, lot # first digit "7") steel or zinc trivalent chromium plated (made on/after 2007, lot # first digit "7", RoHS compliant) steel
-Exhaust manifold interfering thread nut (self locking): Metric class 8.0?, M8x1.25 thread, zinc hexavalent chromium zinc plated (made before 2007, lot # first digit "7") steel or zinc trivalent chromium plated (made on/after 2007, lot # first digit "7", RoHS compliant) steel
-Exhaust manifold to turbo studs and turbo outlet studs: Metric class A2-70?, M8x1.25 thread, 304 stainless steel class 70?
-Exhaust manifold to turbo nuts and turbo outlet interfering thread flange nuts (self locking): Metric class 8.0?, M8x1.25 thread, phosphate plated steel?
-Turbo outlet pipe (aka S-pipe) to exhaust studs: Metric class A2-70?, M10x1.25 thread, 304 stainless steel class 70?
-Turbo outlet pipe (aka S-pipe) to exhaust interfering thread flange nuts (self locking): Metric class A2-70?, M10x1.25 thread, 304 stainless steel class 70?
Due to the fact that different metallurgical types are used on all of the fasteners listed above, you really should use the proper anti-seize compound as I already said.
You will need the following per metallurgical type:
-Stainless steel studs: Nickel anti-seize compound (ie: SAF-T-EZE NPT-.25 or NPBT-8, or Henkel 77124)
-Exhaust manifold bolts and studs INTO head: Copper anti-seize compound (ie: SAF-T-EZE SBT-8C, or Henkel 51147)
-Exhaust manifold nuts to studs: Aluminum graphite anti-seize compound (ie: SAF-T-EZE ST-1, or Henkel 34517)
It is strongly recommended that exhaust fasteners listed above (turbo area/related) be replaced whenever they are removed. If you removed the turbo from the exhaust manifold, for example, then replace all the studs, nuts, and the exhaust manifold bolts. Since the turbo to S-pipe fasteners weren't touched, you can leave them alone. But, if you removed every nut and bolt, then replace everything!
Use of high quality anti-seize compounds will not only make life easier, but there's a possibility of reusing the stainless steel studs (against recommendations) because there's less risk of thread galling. You really get what you pay! The cheap stuff doesn't cut it and only works fine for areas not exposed to high heat. However, due to extreme heat cycling, metallurgical properties of all the fasteners around the turbo changes. They either become too soft or too brittle to provide the correct tensile strength. It is for these reasons why it is recommended that they all get replaced whenever they are removed. If you don't, then there's a great possibility you may run into problems in the near future, such as breakage or one of them falling off. It's just not worth it for the downtime plus having to mill the parts back to trueness again due to warpage!
Due to the hours spent by me reverse engineering these specifications, the pics and information are under copyright. Watermarks and notices have been placed in the PDF to enforce this. Thanks for the understanding.
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