Joined
·
802 Posts
I must admit that when Rick was talking about cleaning all the relays in his car a few weeks back I might have rolled my eyes a bit.
Fast forward to today when my fans stopped working. Examination of the fan/compressor relay on the O/S bulkhead revealed that the yellow/black wire had a melted plastic shield on it, and the spade terminal it fit to showed some corrosion. I cleaned both the spade and the Lucar connector, but to no avail.
(Warning: the centre C2 terminal of the relay is live even without the ignition on. If you clean with steel wool you're likely to get a few strands of stray wool lighting up as they burn. Probably better to disconnect the battery or take the fuse out from right below the relay.)
Disassembly of the relay revealed that the rivet holding the spade connector to the internal post had loosened. This no doubt produced some resistance, generating a bit of extra heat and quickening corrosion, contributing to further looseness, resistance and heat. I cleaned it all off with a wire brush, re-crimped the rivet with a pair of vicegrips, and then soldered the rivet to the spade for good measure.
Testing showed that I still had several ohms of resistance between the common (C2) spade and C1 with the coil energised. I carefully bent the C1 contact post to align it better and then ran some 240 grit sandpaper between the contacts to face them parallel. I cleaned that up with 400 grit sandpaper and some brake cleaner, and all was well.
I cleaned off the flux from the soldering with acetone, taped over the spade contacts and then sprayed the bottom of the relay with lacquer. I think most of the corrosion was caused by the heat rather than the other way around, but better safe than sorry.
So am I going to go through all the relays on the car now? Umm... no. But I can certainly better understand where Rick is coming from.
Jeff.
Fast forward to today when my fans stopped working. Examination of the fan/compressor relay on the O/S bulkhead revealed that the yellow/black wire had a melted plastic shield on it, and the spade terminal it fit to showed some corrosion. I cleaned both the spade and the Lucar connector, but to no avail.
(Warning: the centre C2 terminal of the relay is live even without the ignition on. If you clean with steel wool you're likely to get a few strands of stray wool lighting up as they burn. Probably better to disconnect the battery or take the fuse out from right below the relay.)
Disassembly of the relay revealed that the rivet holding the spade connector to the internal post had loosened. This no doubt produced some resistance, generating a bit of extra heat and quickening corrosion, contributing to further looseness, resistance and heat. I cleaned it all off with a wire brush, re-crimped the rivet with a pair of vicegrips, and then soldered the rivet to the spade for good measure.
Testing showed that I still had several ohms of resistance between the common (C2) spade and C1 with the coil energised. I carefully bent the C1 contact post to align it better and then ran some 240 grit sandpaper between the contacts to face them parallel. I cleaned that up with 400 grit sandpaper and some brake cleaner, and all was well.
I cleaned off the flux from the soldering with acetone, taped over the spade contacts and then sprayed the bottom of the relay with lacquer. I think most of the corrosion was caused by the heat rather than the other way around, but better safe than sorry.
So am I going to go through all the relays on the car now? Umm... no. But I can certainly better understand where Rick is coming from.
Jeff.