morris_marlin
Exhaust Stud Refurb
While cleaning up the engine I removed all the exhaust manifold studs with the intention of fitting new ones as they were pretty manky. When I ordered them from BMW they came to £47 for a set of 24 not including the copper nuts!!! I swiftly canceled that one but trying to source separately is not impossible but difficult as they are a weird M7 size and they were still going from around 1.50 each from scooter specialists (the only other application along with the citroen 2CV that uses this size).
One option was to re-tap the holes in the head to M8 to open up cheaper alternatives but with 24 to do I felt I was opening myself up to a costly mistake.
Following some advice from other builders on the MAKC forum I took off all the rotten nuts in the vice and dropped the studs in hammerite rust removed over night and here are the results after a quick clean up with a wire brush. Not perfect because the threads have been damaged by the rust on the exposed end but certainly reusable given the cost for replacements. I'll put them back in with the rusted end in the head. I'll still need to get new copper/brass nuts but this will be a lot cheaper.
Exhaust Stud Refurb
While cleaning up the engine I removed all the exhaust manifold studs with the intention of fitting new ones as they were pretty manky. When I ordered them from BMW they came to £47 for a set of 24 not including the copper nuts!!! I swiftly canceled that one but trying to source separately is not impossible but difficult as they are a weird M7 size and they were still going from around 1.50 each from scooter specialists (the only other application along with the citroen 2CV that uses this size).
One option was to re-tap the holes in the head to M8 to open up cheaper alternatives but with 24 to do I felt I was opening myself up to a costly mistake.
Following some advice from other builders on the MAKC forum I took off all the rotten nuts in the vice and dropped the studs in hammerite rust removed over night and here are the results after a quick clean up with a wire brush. Not perfect because the threads have been damaged by the rust on the exposed end but certainly reusable given the cost for replacements. I'll put them back in with the rusted end in the head. I'll still need to get new copper/brass nuts but this will be a lot cheaper.