Wiring radiator fans directly from battery, improved electronics and cooling

The radiator fan circuit is a known weak point on 512TR/512M and several other 90s era Ferraris. Fan cycling is known to make the electrical demands leading up to arching and fuse-board delamination and damage over time. Its not a question of if it will happen, but when and to what severity.

We have a similar issue with the 456 and 550 for which I have recently started producing a 'no-cut' / 'no-splice' fan relay harness which bypasses this known weak-point and keeps the factory wiring intact. My harness takes the power load off of the fuse board circuitry and runs the radiator fans directly from the Battery/Alternator circuit via new 70a relays. The original relays and wiring become the trigger point on the new components.

Recently, I had the opportunity to develop a similar harness for the late model US 512TR and F512M (Engine 32438 and up, see diagram 53). On the later 512TR there is a perfect spot to tap positive power via the terminal box on the front of the engine. Running my fused harness to new relays on the oil cooler and then out to each fan connecting using stock components, with grounding points on the chassis nearby. Most importantly this can be done with the engine in, and with basic tools and keeps stock wiring intact. Again, no permanent modifications were made to the car. On the front engine cars at least, most have found improved fan operation resulting in quicker cooling cycles as well. Lengthy discussion has been talked about it on this thread: https://www.ferrarichat.com/forum/threads/550-engine-cooling-improved.622609/

The logic is similar on earlier TR models as well as V8 cars of the era. I am hoping to gather continued interest on other models and try to make them available. I am excited to report the prototype harness in place on the 512TR worked flawlessly. It went on a US model car with no oil cooler fan, so space was easier, but adapting a 3rd relay for the oil cooler circuit would be very doable as well.

Would love to hear thoughts or critiques to hopefully bring these to the Flat 12 platform. Instead of rewiring large swaths of the car's electrical, I am removing one of the higher electric demands from the equation. In lieu of a complete electrical overhaul my harness contributes to, not solves, with a non-invasive solution. Coupled with a few modern options now available for plug and play fuse board replacement, it’s enough to make the electical systems safe and reliable again. At this point its a working prototype and proof of concept.

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Ricambi has been carrying my current version for a few months. Not wanting to turn this into a push for classifieds, so you can search for 'AS1 456/550 cooling harness' for enhanced description as well. I have designed these to be aestheticly camouflaged when installed, yet functional and safe with regard to components.

Link to my YouTube video with install and electrical theory thoughts.

 

Thanks Guido! Have already done your board in my car as well

 

For earlier cars, what is the part number of the red plug under the motor, connectin the battery to the starter/Alternator circuit? The diagrams dont seem to show a part number.

Or Does anyone have a spare i could borrow and see about reverse engineering an adapter to tap power from.

Images used from another thread.
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And that has been one of my thoughts and counterpoints to rewiring the entire front of the car. As RD pointed out, as have others I have been in discussion with, there are still numerous high draw and separate circuits. By adding a separate relay board you can take care of all of them at once. It’s a sound solution, one major electrical overhaul and done. But now with your fuseboard and few other similar fuseboard solutions being mentioned, is it necessary to still separate out the high draw items? Having 4 or more fan circuits on the flat 12 cars, I can see how my approach from the front engine cars (only 2 total fans) doesn’t exactly reverse engineer as effectively. It works, but does it do enough to help the overall stock electrical?

I also approached the original design, with the ‘next owner’ or new shop in mind. On an old VW bus I had to un-fu*ck all the previous owners hack wiring, while still figuring out what was done. Once I redid it to stock form, I found everything worked with good grounds and new ends.
Not having to figure out what’s going on or what’s been changed when troubleshooting or disassembling was very important.

For cars competing in concourse, can judging go that deep looking over electrical? Same question as more of these cars begin to go for Classiche. Granted I can also see the irony, in trying to tell you to put a random harness in the engine bay, but mine can be reverted to stock form if necessary

 

Point taken well said, thank you

 

Hey Jan thanks for reaching out, I will follow up in a separate email in a day or so and we can work something up, i have some questions about your cars current status

Nick

 

I would not agree that at this point in time all original fuseboards are fine. They may have been 'adequate' during production, but as the cars have aged so has this component.

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When I swapped mine, the difference between original and replacement (@theunissenguido) is profound.

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Just remembered this thread is on the TR/512 forum.... my car and pictures are from my 456 board. It's the same issues on the 456 and 550 platform and we have even less fans and various components that need attention to, i consider board (or a modified electrical solution) just another component that needs upgrading or routine monitoring