I have disassembled my Nathan K5LA horns. All the bolts backed out, the backs come off easy. The diaphragm on the trumpet side held by hex heads came off easily. The two back plate metal diaphragms disc that are separated by the rubber wont come off of any of them. I cleaned the edges but cant get them to budge. They appear fairly clean. All the horns work and sounds off great. Is there a trick to taking them off or getting these out to clean, or should I leave good enough alone?
I reckon let them be. If they’re stuck you’ll probably tear or damage them if you pull them out and you’ll need to put fresh ones in. If the horns work, don’t worry about it.
If you really do need them off though, using an air hose and shoving a healthy dose of air pressure between the gasket and the diaphragm might work.