308 Fuse Boxes, Cooling, and Birdman replacements

I though I would post a little about what I did with my 308 fuse boxes. First, in other threads on 308 cooling I stated that I have not had over heating problems with my 308 (85 QV) since it was new. I stated that the temp gage would rise above the 195 level, and peak out somewhere about 1/2 to 3/4 way between the 195 and 220 degree mark. I also said that it had been that way for as long as I could remember. But as I got to thinking about it, it seemed to me that when the car was new the temp never got much about 195.

So a couple of weeks ago I was working on the car in the drive way and noticed the temp was approaching 220. For kicks and giggles I took of the fuse box covers and touched the terminals for the radiator fans Ouch!!! They were very hot. There was a slight sign of the plastic softening but nothing major. Still I decided it was time to install Birdman's new fuse blocks. Order a pair and when they arrived I contemplated the task of installing them. They are well made. No problem their. But I really wanted to retain the original look and the fuse block covers. I decide to pull my old fuse block and see if they could be repaired.

When I pulled them I ohmed the fan contacts and found about 0.1 ohm resistance between the spade connector and the point of fuse contact. That doesn't sound like much but with 15 amps that is about 22 watts of heat generation. Anyone who has touched a 25 w light bulb after it's been on for a while knows they get hot. As the contacts get hot the resistance will also increase.

So I figured that, even though the original fuse blocks were not corroded, they were not the best conductors in the world. Nothing was particularly loose. The rivets were tight. Everything was clean. I also noticed that the fuses themselves were discolored and that the metal "points" where they make contact with the fuse holders were indented and in some cases the metal was actually cut through. You can see this in the second picture. Again, not the best thing for conduction these higher currents.

The pictures below document what I did to repair the original fuse blocks. For the upper rows where several tabs are bridged on the back side it was necessary to solder the tabs to the rivets. The tabs were also soldered to the parts that actually hold the fuse (shown better in the middle figure for the bottom contacts. On the back side I soldered the rivets to the bridge shunts. There was no need to solder to the rivets on the tabs that are not bridged because the rivets only serve to hold the pieces to the plastic once the spade tabs are soldered to the fuse holding clips.

Notice how discolored the original fuses are (from heat). The second fuse form the left is an 8 A fuse and is supposed to be black. All the others are 16 A and should be green. The third from the left is the fuel pump fuse. The ones that are still green are for the rear defroster and headlights which don't get used much (or at all). Thus, I also replaced all the fuses with new one with copper contact rather than the older tin/lead. Got 20 8A and 20 16A for under $10 off Ebay.

The result is that 1) nothing on the fuse blocks gets hot anymore. 2) The car can idle in traffic all day and the temperature barely gets above 195. 3) The windows work better (faster). 4) I presume the fuel pump is also running better. This is all because there is less resistance in the circuits with the result that greater current flows.

So hat's off to Birdman for a great after market replacement fuse block, but if the original blocks aren't too melted they can be repaired. Be careful though. I build electronic stuff as a hobby and I have quality, temperature controlled soldering equipment. If you use too hot an iron or hold it on the contact too long you will melt the plastic and make things worse.

Oh, if anyone needs a couple of Birdman fuse block drop me a PM.
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Funny thing is I never even bothered to look at the fuse blocks before I had the 30k service. Never cleaned it or took the fuses out. As you can see the white block is in good condition. The black was mostly the same with just a little, minor deformation at the top of one of the radiator fan connections. But I never had an electrical problem in my 27 years of ownership other than shot ignition wires.The car has been as reliable as a Honda. Just rolled 30k miles over the other day.

No problem. I'll just keep them on a shelf. You do the community a service.

Oh, and yes, the light bulbs are all original and all work, except for one front parking light.