So as part of the work I've been doing on my cooling system I have replaced the belt driven fan with an electric one, and as part of that project I have decided to replace the little fuse box there in the engine compartment with a slightly larger one to accommodate a fuse for the new fan. According to this little chart 10 amp lucas fuses should be replaced with 7.5 amp blade fuses. If this is accurate my question is if I can't find a 7.5 would it be more acceptable to use a 5 or a 10 amp instead? I had gotten a little kit with a bunch of different rated fuses but 7.5 was not among them and my local stores dont seem to ever have any in stock, but I do have 5s and 10s in abundance.

 

7 amp is quite common and should be available.

 

I say use a 10 amp fuse, at least. There is a huge current draw on starting the fan. But I really recommend that you use a fused relay, powered from the firewall positive post. e.g.
https://mgispeedware.com/product/aut...elay-40a-spst/

 

the wiring kit for the new fan comes with the relay and appropriate fuse for the new fan. In replacing the little fuse box currently in the car there are I think 2 10 amp fuses. Since i'll be going back with blade fuses instead of the lucas fuses that are there now the chart says i should go with 7.5 but I cant find them so im wondering if 5s or 10s would work. I haven't looked at a diagram to see what these fuses are for.

this is the little fuse box I am replacing with one that takes blades.

 

Sardonicus,

I'd be minded to go with Greg's suggestion of a higher amp fuse. However 7.5a is a normal motoring blade fuse size. Hundreds of vendors on ebay.

Good luck

Paul

 

Be careful with blade fuses. Only buy from a name brand supplier. I've seen tests on YouTube where offbrand Chinese fuses can be wildly off their rated value, usually not breaking until well above their rating. Melted wiring is no fun.

Jon