Help please | LamborghiniChat

Help please

Discussion in 'Lamborghini Supercars' started by Spyder-Man, Apr 4, 2021.

  1. Hi all. I had both old cooling fans replaced with the new uprated Spal units, ref:


    Took her out for a local shakedown drive and noted the water temp creeping upwards. Got home, put a meter on the rad thermostat and contacts open for both fans. Not the issue. Today, checked the fuses under the passenger dash. All intact.

    Pulled box in the boot ( trunk) and see that 2 x 15 amp fuses have blown. Bingo. The new fans pull more current I guess than the old units, especially at startup.

    Question. Any concern to uprate these fuses to 20amp?

    What do others run amp wise for their fan units?

    Somebody did a good job replacing the back box. Nice metal construction and even has its own cooling fan, you’ll see in one of the pictures. I reckon a melted plastic box in the past and the previous owner resolved.

    Please would others let me know?


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  3. #2 Ellagirl, Apr 4, 2021
    Last edited: Apr 4, 2021
    Hi there. I posted a reply to you reg this a while back I uppgraded my fans 2-3 years ago and bench tested them with a fuse holder and a toggle switch in my garage prior to innstall. My findings where the old fans would need 7amps for initial start. While the new fans needed 15 amps min to start. I am writing this from my hotel room in Vail and could be off slightly on the nmbrs. But with my bench run befote innstall I established a real amp nmbr. I run 20 amp fuses in my car and does not have any issues also keep in mind i am in Florida, and pretty much always run in 90 degree heat. Hope this answers your questions. If you go back on the DD section you might find my okd post on this.also i am surprised the company who innstalled your fans did not adress this during the innstall. Once you put your hands on these new fans and turn them, you can tell they need higher amp fuses, hence my garage/home fuse test.
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  4. That is a nice well built box. When you google the fan motors, does it say anything about electrical requirements? I would think 15 amp would be fine for each fan. 20 shouldn’t be a problem, especially if the surge is just initial.
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  5. Hi and thanks very much Nils. Your post makes complete sense and I appreciate your feedback. I have some automotive blade fuses on order and will look to fit 20 amp units in good faith.

    Many thanks.
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  6. Afternoon Mr Cat. Yes, got the specs off the web. As per the below. So standard sea level pressure from old my old piloting days is 1013mb. Comes at at around 10 mm h2o, equates to around 16 amps. So looks like 20 amp should do it.

    Yes, the box is a nice upgrade. Great that the previous owners took good care of madam ;)

    My best

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  9. Hi Mike, seems I have a circuit / relay per fan as two fuses were blown. I'll get a meter on the wires later today and chase out the wires and confirm that both blown fuses do indeed relate to a single fan circuit. I did replace the fuses last evening with 20 amp and jumped circumvented the switch, but with ignition on, nothing still. I'll need to check the relays next. Not sure if they could have blown?

  10. #8 raymondQV, Apr 6, 2021 at 4:26 AM
    Last edited: Apr 6, 2021 at 4:32 AM
    Sure it does, 20A mp should be OK - 15 is too less, worked always fine in the Mimran QV - 12Vd305.FH10 (

    The plastic fuse box is a joke... Lamborghini Countach #GLA12997 Fusebox
    This issue is well known and also our passed away L-Talk first owner JRV was documenting it >15 years ago:
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  12. OK, so the problem is solved, fans working. 20amp fuses fixed. My shorting the thermo switch technique is to blame. Duh ! :eek:

    On the subject of the thermostat, it has (as per the picture) 3 terminals. Common and 2 poles. Both of my fans come on at the same time. Chasing the wires back to the relays, it appears that green blue cable is connected to nothing. Both fans are on one relay and the trigger for this is the white and green cable.

    All I can think off is that this setup may have been installed for 2 speed fans? Did the Countach have 2 speed fan's originally? Does anyone else's thermostat have 3 terminals? Maybe the thermostat has switches for 2 different heat temps in the rads ?

    Be interested to know.


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  13. Easy question, depending on the fan setup the blower fans in front of the radiator are added depending on the temperature.
    In the Mimran QV we made it even better, on the first stage the fans ran in serial mde, means low speed, when higher temp was reached they were switched to parallel mode, means both at full speed, a good electrician can install this easily.
    BTW your bridging is quite normal, I used to open the black connector (the white plastic) and hold it to the other connector.
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  14. #12 Ellagirl, Apr 6, 2021 at 5:04 PM
    Last edited: Apr 6, 2021 at 6:29 PM
    My cars factory wiring is as follows. Once a certain temprature is reached, the driver side puller(rear)and passenger side pusher(front) comes on. Once the next level temp is reached , the driver side pusher(front) and the passenger side puller (rear) comes on. Iow, they pull diagonally.criss cross There is 2 relays total. Also one breaker for each fan. I also did a complete rebuild of my box ,with top notch marine products. Also i will add, it takes a lot of sitting in traffic time, even in Florida, for the second set of fans to turn on.
  15. This is not correct, normally the pullers kick in first, then both pushers.
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  16. Hi and thanks for the info Raymond. My car has no front blower fans, just the two pullers. So, as it's working, I'll leave this well alone now :)

    Glad to know I'm not alone on a rubbish bridging technique. I've now got a custom piece of wire left in the car that can, in an emergency, be used to bypass the thermo if required.

    Many thanks to all that have shared their wisdom.

  17. Interesting. I double checked everything prior to my fan innstall and connection/connector block in the electrical box, my fans was for sure connected diagonally from the factory, also the cooling performs perfect, it was probably never discovered at the final factory test run, that beeing said, after reading the misc stories on this chat room over the years, its really only 2 wires swapped on the connection block wich is causing this, and would really not be a big story in comparison to some others. Raymond, knowing your extensive experience with the Countach,over the last 30 years, i have no reason to doubt your comment reg the factory fan sequence, i will swap the the wires on the puller Pusher passenger side, then monitor my temp gauge on my next drive. Thanks for the info
  18. Nils,
    That would be an interesting experience when you change them, please let us know.
    From the past I got to know that pullers are more efficient than pushers which underlines my knowledge that the pushers were only added for hot regions and only used when the engine gets hotter.
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  19. Esattamente.
  20. Here is a drawing I made showing how I re-wired my cooling fans. As you can see, I have 1 fuse and 1 relay for each fan. As others have pointed out, the fans are triggered by a 2-stage thermostat. When the water temperature hits 176F, the puller fans kick on. Should the water temperature continue to rise, when it hits 190F, the pusher fans kick on as well.


    Attached Files:

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