Alternator upgrades

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BAIT
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Re: Alternator upgrades

#526 Post by BAIT » Fri Mar 31, 2017 10:59 pm

bumpstart wrote:at the cost of a few cents . would you not change the diode anyway?
i usually run three 3A as a gang ( yes i know they dont shed evenly as they warm ) so i have a proxy 9A

only time ive seen it go bad, and they tested ok to me on DMM
but still one must have leaked was the relay would buzz when the light was activated until the alternator kicked in
Thanks Bump
Yeah running 2 axial 6amp diodes in parallel, very strange never seen a diode reverse bias and read correct on my DMM in the 20 odd years of doing electronic (switchmode PSU's repairs)...Learn something new everyday :D

Ok will buy a few more and see if that fixes the issue.

Appreciate your help mate!

Cheers
Rob

Edit:
Ok today I replaced the diodes and still wouldn't switch off with key :(

Thought to test back feed on the ignition wire I soldered in a diode as in pic below, and it functioned as normal and turned off with key.

That would suggest the internal regulator does indeed have a inbuilt diode to prevent back feed to ign wire. So time to have the alt rebuilt :)
Attachments
wiring.jpg



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Re: Alternator upgrades

#527 Post by Fisco » Sun Nov 05, 2017 3:27 am

Hi folks,
Useful thread this. Am converting my Rx3 to an internal reg alternator from a Montrose/929, mainly just to clean up some wiring and get rid of the external reg. Couple of questions:

1) Where is the charge light on the Rx3 dash? I'm thinking the bulb has probably gone on mine as no end of testing has managed to get it to light up. I also cannot find its location in ANY Rx3 wiring diagrams.
2) My "6 pin" connector only has 5 wires, and none of these are yellow/blue. Could it be that the missing wire is the charge indicator wire and my car doesn't have this circuit? Seems odd (but aligns with not being able to find the charge light in the wiring diagram lol)
3) More of an observation than a question but on Sim_rx3's drawing for the "Rx3 to internal reg non load sensing" image on the first page, would it not be better to connect into the black (ign) wire closer to the key or fuse box to give the alternator a better reading for the actual voltage in the system, or is the difference minimal so not worth the extra wiring hassle?

Cheers



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Re: Alternator upgrades

#528 Post by bumpstart » Sun Nov 05, 2017 10:30 am

1:
rx3 ad early rx2 have amp meters. not a light . though easy to add an LED to the dash / when you upgrade the alt the amp meter MUST be isolated ( wires removed and bridged ) as it will not handle the current pushed through it
2:
yeh
3: depending which diagram you are reading the s4 type hooks to ignition switch to sense load and s5 hooks to the battery B+ to sense load
thats how they work. no need to think too hard about it . sim is making it so you can use a wire and plug that is convenient in the bay and no pull something the length of the loom for a zero or negligible win


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Re: Alternator upgrades

#529 Post by Fisco » Mon Nov 06, 2017 4:30 am

Thanks bumpstart, that explains why i couldn't find it :lol: Was just following the info on the first page.

So for basic system just need two wires to the alternator? One to the switched battery positive (from black wire from ignition key) and one to the B+ positive connection from the battery via the ammeter?

Will prob add a light at a later date but just trying to get the thing on the road first.



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Re: Alternator upgrades

#530 Post by bumpstart » Sun Nov 12, 2017 1:45 pm

yes . that is all that is required. the light circuit has some play in the initial field excitement at first startup
but with it left off all alts will enable themselves on the first rev up ( noticable with the lights on )


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Re: Alternator upgrades

#531 Post by Fisco » Tue Nov 14, 2017 6:23 am

Perfect, thanks. Yes had read somewhere the lighting circuit had something to do with initial power up but sounds like I can live without that. Am fitting a voltmeter too with alarm function so will know when there's a charge problem.



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Re: Alternator upgrades

#532 Post by SP2333 » Sun Feb 25, 2018 8:37 pm

Could I kindly get some assistance with installation of a Series 6 alternator into my sons 1982 Series 2 Rx7.

Ive read through the thread but too much confusion.

I understand i need to upgrade the main B+ lead from the big post on the alternator, removing the standard white/red stripe wire and directly to the battery positive (With a 100A fuse inline ???)

The original alternator has a 2 wire plug on the back with a white / black stripe wire and a white / black stripe.

If can kindly be directed what to do with the two small wires and weather i need to install the mentioned relay/diode circuit.

Im quite capable to carry out the job, just need some advise. A simple diagram would be much appreciated (Series 6 into a Series 2)

A



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Re: Alternator upgrades

#533 Post by KYPREO » Sun Feb 25, 2018 9:25 pm

SP2333 wrote:
Sun Feb 25, 2018 8:37 pm
Could I kindly get some assistance with installation of a Series 6 alternator into my sons 1982 Series 2 Rx7.

Ive read through the thread but too much confusion.

I understand i need to upgrade the main B+ lead from the big post on the alternator, removing the standard white/red stripe wire and directly to the battery positive (With a 100A fuse inline ???)

The original alternator has a 2 wire plug on the back with a white / black stripe wire and a white / black stripe.

If can kindly be directed what to do with the two small wires and weather i need to install the mentioned relay/diode circuit.

Im quite capable to carry out the job, just need some advise. A simple diagram would be much appreciated (Series 6 into a Series 2)

A
This is the diagram you want to use:
altupgradegen1toseries5alt.jpg
The plug for the series 2 is an L/R type alternator. The "L"(or warning light) wire is the white with black trace (horizontal terminal on the T plug) and connected to the instrument cluster via the choke and check relay. The "R" wire is the regulator wire and connects to the ignition switch via a 15A fuse. It is the black with white trace - the vertical terminal on the T plug. The standard wiring diagram for Oz delivered s2 is below:
20180225_211601.jpg
Now the factory 'R' wire going to be thrown in the bin, because you are going to wire the new 'S' terminal on the FD alt to a battery positive source using upgraded wiring and a 20A fuse. If you are looking at the plug on the FD alternator - the S terminal is the one on the left when viewed with the prong section at the top.

For the 'L' terminal, you could theoretically just hook up the factory white with black trace - this assumes your wiring is standard. I had no trouble wiring it this way. If you don't have the choke and check relay, following the diagram above. White with black goes to relay using a 10A diode.

hope that makes sense!


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Re: Alternator upgrades

#534 Post by SP2333 » Mon Feb 26, 2018 5:01 am

Thanks for the detailed reply.

Ok I’m all good for the most part in my head now I think.

Just to clarify,
The L terminal I’m going to hook up to the original WB wire and the factory choke and check relay should take care of it without installing an extra relay. One thing, do I need to fit a diode in series in this wire?



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Re: Alternator upgrades

#535 Post by omp » Sat Mar 24, 2018 11:39 pm

Hello

Where did the data for the current capacity of the cable (8G or 10mm2) come from?

From what I can find, it varies so much, anywhere from 46A (a few places),56A (Jaycar 8G) to 90A (Olex Cables - Welding).

I have gone bigger again in my RX2, which has a 100amp "RXA269" alternator.

It was wired extremely weirdly (power side).

Hope you can follow.

Battery in boot

Down the passenger side was run 2G to the starter motor, from the starter motor was 4G to the alternator "+" stud. No protection between the alternator and starter for overload protection.

Down the drivers side was 10G from the Battery (again, no protection) to drivers side of the engine bay where it met up with the standard IGN wire (Big W/R wire), which continued around to the alternator to join up with the 4G cable from the starter. This W/R wire had been lengthened though with a piece of 4mm2 cable lol! The stock wire looks to be around 6mm2.

The car is off the road at the moment (gearbox rebuild, getting a few things sorted), so I have disconnected that "extended" original/stock R/W wire from the alternater and bumped the 4G cable from the starter to 2G and placed a 120amp circuit breaker between the Alternator and Starter.

I will be fixing the drivers side wiring too, that will be upgraded, protected by a circuit breaker and split into 2 circuits, 1 for the "power" (IGN) and the other for when I upgrade the headlights to H4s.



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Re: Alternator upgrades

#536 Post by Dezza32 » Sat May 12, 2018 10:45 pm

Ok so im new to rotas iv just brought my mates series 1 rx7 with 12a im takeing that out to put in a 13b. Now for some reason i can seem to see any of the diagram pics on the thread. But what im wanting to know is how much of the wireing in the engine bay can i do away with as want to go to a internal reg altinator but also clean engine bay/wireing up while there no engine there. How many of the other regs/boxes do i need to keep? also am thinking about relocating battery to the boot.
Any advice or help would be appreciated :D



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Re: Alternator upgrades

#537 Post by KYPREO » Mon May 14, 2018 1:50 pm

Dezza32 wrote:
Sat May 12, 2018 10:45 pm
Ok so im new to rotas iv just brought my mates series 1 rx7 with 12a im takeing that out to put in a 13b. Now for some reason i can seem to see any of the diagram pics on the thread. But what im wanting to know is how much of the wireing in the engine bay can i do away with as want to go to a internal reg altinator but also clean engine bay/wireing up while there no engine there. How many of the other regs/boxes do i need to keep? also am thinking about relocating battery to the boot.
Any advice or help would be appreciated :D
Hi and welcome to the forum 8)

Images hosted on Photobucket are blocked from being linked on 3rd party websites like this. There is a workaround - see here: viewtopic.php?p=2817906#p2817906

The diagram you need will depend on the alternator you get. Anything from a series 2 RX-7 onwards is internal reg, but the different alternators have different current output and different wiring requirements. Series 5 is different from series 4 etc. So depends on what alternator is on the 13B. I can post up the diagram you need based on what 13B is being fitted.

You can clean up the engine bay/wiring to get rid of the external reg and while you're at, the fusible links. The relays you need to keep depends on lots of factors: do you have aircon, what is controlling your 13B - ECU? etc.

More info on moving battery to the boot: viewtopic.php?f=16&t=31504 (use the Photobucket fix to see the images)
More info on replacing fusible links with fuses: viewtopic.php?f=16&t=110012
More info on replacing fusible links with fused distribution block and other electrical mods: viewtopic.php?f=4&t=12141

Hope this is a good start.

Shoot away with any other questions you might have.


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Re: Alternator upgrades

#538 Post by Dezza32 » Mon May 14, 2018 9:00 pm

Cheers Kypero
So at this stage my plans are to go a s4 13b na running a ida (planing on getting through mazfix)so no ecu or anything like that. As for aircon was already removed before i got car as it still has the original 12a in it.



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Re: Alternator upgrades

#539 Post by KYPREO » Mon May 14, 2018 9:19 pm

OK cool. s4 will be good for your application and should be relatively straightforward. S4 is wired up similarly to s2/3 (but higher capacity - 70A) and is the same concept as upgrading 808/rx3 alternator to an internal reg type.

Follow this diagram, but the wire colours going into the 6 pin plug for the external reg may differ:
808rx3externalregtointernalregalt.jpg
I have the s1 rx7 wiring diagram and can post up here for you if need be. It may take another day or 2 though.


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Re: Alternator upgrades

#540 Post by Dezza32 » Tue May 15, 2018 2:12 pm

Thanks heaps mate yeah the rx7 1 be good as well please.
Thanks again huge help



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