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Author: Matt Webb
Email: MattWebb502@yahoo.com
Date: 05/01/2006
Subject: Fiat 124, replacing fuse block with an ATO style.
Resources: first hand experience.    

Parts required   From www.mcmelectronics.com
2x MCM p/n 28-1185,
five gang ATO fuse block
1x MCM p/n 28-6073, 0.250 flag disconnects,
bag of 100 1x MCM p/n 28-6092, flag disconnect sleeves, bag of 100      
some heat shrink tube in various sizes/etc.
some 10 and 12 AWG stranded wire solder,
soldering iron
epoxy 1/8" steel plate
crimp connectors      

In the pic below you can see the new fuse block mounted in place as well as the adaptor plate that must be fabricated out of 1/8" steel.      

About the Adapter Bracket   Because the new fuse block does not have rear exit connectors the adaptor must be made to provide a small gap along the top edge to allow the wires to safely pass through without risk of chafing. In the pic above you can see where the bracket was notched out on the lower left hand corner this is to provide clearance for the hood release lever. so keep things tight to ensure no problems here. Sorry I don't have any specifics on the bracket dimensions/etc. Just get under there and make measurements. not too hard to fab this up. Most important thing is keeping clearance for the hood release!     The fuse blocks  

What you see in the picture is actually two fuse blocks butted together end to end. Each block consists of five fuse sockets and mount points on either side.   The stock setup in my 124 had 9 fuses IIRC. . I happened to have an extra block, so I used a couple extra sockets and ended up with 12 sockets. 1 spare, 1 added circuit for my fuel pump and electronic ignition, and I split one of the stock circuits up into two for easier troubleshooting in the future. The fuses in place aren't necessarily the values that will be used. . they were put in place to take pictures.  

Slight modification required to get them looking like they do here. attention to detail here will give you a nice tight fuse block --- when you first get them the sockets are all loose and cheap feeling, but they're nice.Hard to explain this really, you need to have them in your hands to really understand what has to be done.    

Wiring it up   This is no place to go practicing your soldering skills. If you're good, go for it. If you aren't so good with an iron then I wouldn't go messing with it. you're just asking for problems. Practice elsewhere first.   Basically you want to let the old fuseblock hang in place as you move one wire at a time from it to the same location on the new fuseblock.Because the stock block has rear exit connectors you will have to extend all of the old wires slightly. I added in about 3" of new wire to each one. Also with the old block some of the spots are actually junction points for more than 1 wire. I just removed these points, soldered the wires together and soldered my extension pigtails to them. don't forget the heatshrink tubing.  

It is helpful to make the extension wire complete with the flag disconnect and attach it to the new block first. this way you can help minimize stress at the connectors. otherwise you could end up with a wire that must be twisted in order to connect it to the fuseblock. NOT a good thing, especially with the short runs of heavy gauge wires and the flag disconnects.   In my case I didn't have the best of luck getting these flag disconnects to crimp properly. no problem though because I intended to crimp and solder them. If soldering them make sure the connectors face upward to prevent the solder from running into and clogging them.When soldering to the new extension wires to the existing harness wires I used crimp connectors make sure you have real good connectors and, more importantly, HIGH QUALITY CRIMPERS. the flimsy piece of junk crimpers are a no no. Go to Lowes or Home Depot and get a pair of the Klein crimpers (NOT the GB ones!) http://www.service.kleintools.com/Marketing/Catalog_Imagery/1005_icon.jpg I slit the insulation of the crimp connectors, crimped well, followed up with solder – provides a better bond and keeps moisture OUT. Don't forget to put that heat shrink tube in place before you solder / crimp!  

More pics   Notice in these shots you can see where a few of the flag disconnects are skewed / stressed. try to avoid this as much as possible! The switch you see is a manual over ride for radiator fan relay control.