main fuse with FD alternator
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main fuse with FD alternator
I have an extra FD alternator with a double FC pully that I am going to put on my TII. Since its 100A and not 80A like the factory one do I need to change the main fuse from 100A to a 120A like the FD uses?
Thanks
Thanks
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Subscribing to this thread!!!
I'm looking at doing the same alternator swap. Which pulley are you using? I found an Ebay pulley for FCs but made to fit on FD alternators.
http://cgi.ebay.com/ebaymotors/ws/eB...TQ:MOTORS:1123
I'm not too into the rotor on the end, but it's the only pulley I've seen that combines not being underdrive and doesn't need to be machined to fit an FD alternator.
I found this thread...at the end someone posts to put in a 100A fuse, don't know if that's helpful or not. But I found the information about the alternator post useful.
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/just-installed-fd-alternator-keep-blowing-main-fuse-302628/
Found this one also.....
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/new-s6-alternator-upgrade-main-fuse-578886/https://www.rx7club.com/showthread.php?t=578886
I'm looking at doing the same alternator swap. Which pulley are you using? I found an Ebay pulley for FCs but made to fit on FD alternators.
http://cgi.ebay.com/ebaymotors/ws/eB...TQ:MOTORS:1123
I'm not too into the rotor on the end, but it's the only pulley I've seen that combines not being underdrive and doesn't need to be machined to fit an FD alternator.
I found this thread...at the end someone posts to put in a 100A fuse, don't know if that's helpful or not. But I found the information about the alternator post useful.
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/just-installed-fd-alternator-keep-blowing-main-fuse-302628/
Found this one also.....
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/new-s6-alternator-upgrade-main-fuse-578886/https://www.rx7club.com/showthread.php?t=578886
Last edited by Aaron Cake; 12-29-07 at 10:34 AM. Reason: Merge three posts
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Upgrading the alternator does not suddenly increase the current flowing through the fuse. The electrical system will draw exactly as much current as it did before, you just have more spare capacity.
If you're upgrading the alternator to handle additional electrical devices like stereo gear or an e-fan, nothing like that should be running through the stock electrical system anyway. They should be fed from dedicated circuits run directly from the battery with their own fuses.
So like Aaron said, you don't need to change the fuse, and in fact you shouldn't.
Last edited by NZConvertible; 12-29-07 at 05:19 PM.
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Then why did the factory progressively upgrade the fuse rating? The only part of the car that varied significantly in amperage was the alternator. Each time the factory changed the alternator, they also changed the fuse. We change the alternator...what should we do?
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I really don't care whether someone does it or not, and long as they don't claim you need to. That would be BS, and there are some of us who try to keep the technical sections BS-free.
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I would agree that you dont need to, but I would say that you dont need to do the alt conversion to begin with...so if we went around refusing to discuss things that we dont need to do, we would all be driving bone stock 20 year old cars, and it would be kind of boring, dont you think?
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If someone need the extra amps, (car audio, Efan, whatever reason they need more power) then they will need the alt upgrade. You are arguing just to argue.
I don't think it would be too good of an idea to raise your fuse in almost any circumstance. It would just give greater tolerance if something did go wrong (a ground out or something).
I don't think it would be too good of an idea to raise your fuse in almost any circumstance. It would just give greater tolerance if something did go wrong (a ground out or something).
#15
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...so if we went around refusing to discuss things that we dont need to do, we would all be driving bone stock 20 year old cars, and it would be kind of boring, dont you think?
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I'd just like to say that I did not in fact fling the first poo, I simply provided links to threads with related topics, which I did not in fact endorse or deny. I plead the 5th!!!
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I'll be hiding behind the couch with Lysol....
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#17
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Then why did the factory progressively upgrade the fuse rating? The only part of the car that varied significantly in amperage was the alternator. Each time the factory changed the alternator, they also changed the fuse. We change the alternator...what should we do?
Are you trying to imply the FD3S has the EXACT same current draw as the FC3S?
Think about it...
One obvious point is that the FD doesn't have a mechanical fan, and it runs twin electrical fans; there's your 10A+ current draw right there.
This is not a question about upgrading...
Unless you change the CURRENT DRAW through the stock electrical wiring on the FC, why would you need to change the fuse?
Do you change fuses cause you run bigger batteries???
-Ted
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Replacing the 80 Amp fuse with a 100 Amp fuse will allow 100 Amps to pass through an 80 Amp circuit in the event of a short. This means that the circuit and components will be damaged before the fuse breaks to protect it. So your logic defeats the whole purpose of a fuse
It doesn't matter what the power supply is capable of producing, you have to look at the rating for the circuit drawing power. You can hook the car up to a nuclear power plant producing gigawatts of power and still protect it with an 80A fuse because the car is still only pulling 80 amps. All the rest of the **** you add to the car like an electric fan, aftermarket stereo, etc... has its own fuse and is not usually connected to the main engine fuse circuit so it does not increase the draw beyond 80amp. These things will usually be attached directly to the battery since they have their own fuse to protect them.
It doesn't matter what the power supply is capable of producing, you have to look at the rating for the circuit drawing power. You can hook the car up to a nuclear power plant producing gigawatts of power and still protect it with an 80A fuse because the car is still only pulling 80 amps. All the rest of the **** you add to the car like an electric fan, aftermarket stereo, etc... has its own fuse and is not usually connected to the main engine fuse circuit so it does not increase the draw beyond 80amp. These things will usually be attached directly to the battery since they have their own fuse to protect them.
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Geez guys I did not know it would cause such a big deal. :-) My car has the 100A main fuse since its 91 RHD TII and I just wanted to ask if it is better to change it. I have no electrical problems with the car and now that i think about it it is not such a good idea to change the main fuse. I am running a mechanical fan (which I think nothing cools better than it) but I was thinking of putting an electrical fan (Flexalite FLX 180) which draws 18amp just for clearing out my engine bay. I am using a Ron Davis Racing radiator which is almost 70mm thick. I will put the FD alternator in only if I switch to an electrical fan.
Thanks
Thanks
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in short Do NOT change the fuse, the WIRES are rated at 80 AMP so if you allow 100A to run through them they will melt and will catch on fire and you will not have a car...
the wires may handle 100a but its doubtful they are old and frail to begin with, so just be safe and don't tempt fate.
edit: just looked at the amps you are running again, it really doesn't matter what you have you should never up the amps of a fuse, the wires are rated at just over that fuse, so that if it say spikes to 105amps the fuse will blow, but the current still spikes in the wires, so they can handle higher than rated fuse, but not for long periods of time,
the wires may handle 100a but its doubtful they are old and frail to begin with, so just be safe and don't tempt fate.
edit: just looked at the amps you are running again, it really doesn't matter what you have you should never up the amps of a fuse, the wires are rated at just over that fuse, so that if it say spikes to 105amps the fuse will blow, but the current still spikes in the wires, so they can handle higher than rated fuse, but not for long periods of time,
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Geez guys I did not know it would cause such a big deal. :-) My car has the 100A main fuse since its 91 RHD TII and I just wanted to ask if it is better to change it. I have no electrical problems with the car and now that i think about it it is not such a good idea to change the main fuse. I am running a mechanical fan (which I think nothing cools better than it) but I was thinking of putting an electrical fan (Flexalite FLX 180) which draws 18amp just for clearing out my engine bay. I am using a Ron Davis Racing radiator which is almost 70mm thick. I will put the FD alternator in only if I switch to an electrical fan.
Thanks
Thanks
With that said, I agree that changing the fuse from the factory rating is not a good idea.
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BTW I ordered a dual belt pulley last night
http://www.rotaryinnovation.com/new_products1.htm
I haven't gotten an FD alternator yet and am more concerned with having no air pump with a single belt alternator pulley. On the hottest day of the summer I sheared off my alternator pulley on the highway, before I realized what had happened I blew the top off my radiator. Luckily, there was no damage to the engine and I ended up getting a nice Koyo.
Learning is such an expensive road....
http://www.rotaryinnovation.com/new_products1.htm
I haven't gotten an FD alternator yet and am more concerned with having no air pump with a single belt alternator pulley. On the hottest day of the summer I sheared off my alternator pulley on the highway, before I realized what had happened I blew the top off my radiator. Luckily, there was no damage to the engine and I ended up getting a nice Koyo.
Learning is such an expensive road....
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in short Do NOT change the fuse, the WIRES are rated at 80 AMP so if you allow 100A to run through them they will melt and will catch on fire and you will not have a car...
the wires may handle 100a but its doubtful they are old and frail to begin with, so just be safe and don't tempt fate.
the wires may handle 100a but its doubtful they are old and frail to begin with, so just be safe and don't tempt fate.
edit: just looked at the amps you are running again, it really doesn't matter what you have you should never up the amps of a fuse, the wires are rated at just over that fuse, so that if it say spikes to 105amps the fuse will blow, but the current still spikes in the wires, so they can handle higher than rated fuse, but not for long periods of time,
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Even if you did that, there'd be no need to touch the stock MAIN fuse because the fan would be powered directly from the battery via its own fuse. The current through the MAIN fuse wouldn't change.