The Infamous Series 2 Fusebox


Well-Known Member
Hi Stan,doing the blade conversion today..can you tell me,were your fuse value conversions satisfactory?
Cheers,Pete (see you on facebook,lol)
Good for you, won't regret it.

Yes, no problem....not had to up any of the ratings, and not had any blow so far. There....I've said it now, haven't I? ;)

I look forward (NOT!) to getting into this area soon with a 3500S. Just to put things in perspective, below are pics of front and rear of a Porsche 928 fuse board, early model with bullet fuses. I am in the final stages of converting mine to Blade fuses with some soldering involved....on 34 fuse holders.
First impetus was a failed pump relay, and a visible spark at the fuse holder. At least all the incoming and outgoing leads are connected by plugs!

sheesh . was thinking up upgrading to Blade fuses but keep putting it off. car is over 40 years old and still on original fuse box. hhmm .why change whats never gone wrong versus others having issues and peace of mind. think I might opt for 2 x6 way blade fuse box and book in for mental health check after a week .ought to be about ling enough to have driven me mad as well aware limited room and length of wires issues. however glove box is currently out might bite bullet and go for it.
My plan is to offload the high current items to relays - headlights and horn are high on the list. Also useful to forestall problems is to check the tightness and cleanliness of the fuseholders and fuse ends, and give all contacts a touch of something like Deoxit to improve conductivity. Once I get to examine the fuseholder in detail I will see how hard it might be to convert to blade fuses, and advise - the wiring at the back seems to be a major issue. Will look for a spare unit to experiment on.
My fuse box did this a few years ago......
IMAG0011 (2).jpg IMAG0011.jpg
This was the headlight fuses and I fixed it by adding some external blade fuses like this.....


It has been a satisfactory fix now for some years. I believe that my problem was because I fitted a halogen headlight conversion which virtually doubles the current requirement. I don't know why this seems to happen though in general for other fuses? Maybe it is just headlight ones that are affected? I don't really believe the imperial/metric fuse idea as we have been using metric fuses for thirty years or more, and in practice they have a very small contact area anyway. Maybe they always melted, but you would have thought if it was common back in the days of production, then Rover might have done something about it in terms of a recall rather than have their new cars go up in flames all over the place!! Of course it could be to do with additional current required due to the lovely bullet connectors all over the wiring looms corroding away merrily?? Who knows!
Hate to keep harping on the 928 electrics, but I think the problems are similar - slow creeping degradation of contacts. The 928 forum at rennlist has an electrical maintenance check list - recommendations based on years of experience - to be performed ANNUALY. Locate all ground connections, open/undo fixings, clean until bright, Deoxit, tighten fixings; remove each fuse, clean contacts and the socket (where possible), clean, Deoxit, refit. Same with all relay blades. I burnt out 2 fuel pump relays before I found the pump fuse socket sparking , and started on my blade fuse conversion project. 928s go back to 1979, so they are not much younger than the P6s, and used bullet fuses (with much smaller contacts than our glass units) until 1985 but electrical problems are endemic in all years.