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Blade Fusebox Upgrade

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sultanoswing

sultanoswing

Jedi Hopeful
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I'm thinking of a simple swap out of the 4-glass fuse box for a 4-blade fuse unit. I'm aware there's a kit for this (Ian's Eightup Page) but I just want to grab an off-the shelf four-unit box for the stock under bonnet location.

Any experience doing this? I'm assuming 20Amp blades are the appropriate rating, from what I've read here and elsewhere.
 
I've swapped out many a different fusebox on older car ( for upgrades and trick wiring systems) but I still have the old one in my MGB for right now.
I'm not at home so I don't have my notes but when I speced out a fusebox to replace mine I went with a 6 position engine compartment rated blade system that I remember seeing around at several universal wiring suppliers.
I believe that the 20 amp rating is OK for stock but I seem to recall something about the fuel pumps draw that made me want to isolate it from all other lines. I am also adding air to the B ( Yea the wife wants it. I like pressing on the pedal with the top down ) so thats why the extra poles.
If I can get a break I'll try and look up the fusebox again but my students are pretty confused and may need more attention this evening.
 
There is nothing wrong with the original fuse box, you just need to keep it clean and free of corrison. An original replacement is available for fairly cheap. Most electrical problems happen on MGB's when owners start trying to 'improve' them.
 
I agree wholeheartly the original is fine if it hasn't been tweeked by some well meaning previous owner. I just like to add accesories that may not have been original but can enhance the driving pleasure and the original does not bode well for modifications.
 
Well Sultanoswing, I am just wondering if they do not have breakers over there? About $90.00 US + carriage for a piece of plastic and some wire seems a bit over the top to me----Keoke /ubbthreads/images/graemlins/confused.gif
 
Just my opinion, but adding fused RELAYS is a far better/safer way to deal with any additional accessory loads (relative to an upgraded fuse box).

I have 4 Hella fused relays on my MGB (high beam circuit, lowbeam circuit, fog light circuit, air horn). Here's a photo of the high/low beam circuit. There's an identical pair on the other side for the fog light/horn.

relays.jpg


The idea behind a relay is to transfer the load from the original wiring over to a new heavy gauge/high current circuit (which is easy to wire). The original wiring only handles the current to power the relay coil - a trivial amount.

The original fusebox is cheap; if you suspect trouble, just replace it with the stock part.
 
Nice mod and works far better than the voltage drop of having the lights power running all over the car.
I have no problems with the original fuse block if I'm leaving the car as a pristine original but if I'm going to the trouble of adding additional circuits I like to have a few spares and a few options in my harness.
I normally rip the entire harness out and modify it before I reassemble the car.
 
Thanks for your input, guys...I think I'll stick with stock for now (although the fusebox cover is missing!)

The only accessory I'm adding is a 4x45 watt CD/MP3 player. Scott_Hower: That's a nice looking (and functioning) setup. Your car is even the same colour as mine! I'm just in the process of setting up a relay for the stereo right now /ubbthreads/images/graemlins/smile.gif
 
[ QUOTE ]
Same color, but there's something very wrong with your steering wheel.

[/ QUOTE ]

Oh how right you are! It's someone else's aftermarket replacement for whatever reason. Believe me, an original is on my shopping list!

I'm now half way through my stereo installation (got dark). The relay is in place and wired up - tomorrow - sounds! This really is fun - I've got my heat shrinks and crimping down pat- although my soldering still needs practice!
 
psst... sultanoswing, I believe Scott was refering to the steering wheel being in the passenger's seat... /ubbthreads/images/graemlins/laugh.gif

*whistles innocently*
 
[ QUOTE ]
steering wheel being in the passenger's seat... /ubbthreads/images/graemlins/laugh.gif


[/ QUOTE ]

Bloody Americans! (and Europeans etc) /ubbthreads/images/graemlins/laugh.gif

...talk about the biggest 'after market mod' ever to befoul good ol' British motor cars - the LHD conversion!!! /ubbthreads/images/graemlins/smile.gif
 
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