LongDuck

Found that my short was due to alternator (*specifically what Mazda calls the Rectifier inside the Alt), and replaced it with a known good and back on the road. Was curious if you guys have had success rebuilding these, as the FSM says you heat certain portions with a hot iron for 4-5min to melt the solder that holds it together, and sounds involved, plus I don't have new Rectifier parts to install once I get it apart.

Rebuild? Replace (reliable sources)? Upgrade? Available from Mazda still? Thanks,

GSLSEforme

I took mine apart,had a noisy drive end bearing.
I wanted to service rear bearing,had the same amount of miles...
To remove rear bearing you have to heat rear alt case to release the bearing shell. Mazda stipulates to use a LARGE soldering iron to do this,don’t have a large one only a small 15 watt iron for low temp delicate stuff.
Do have 100/140 gun and 150/200 gun- neither suitable for the heat needed.
I have an induction heater,intended use is to heat seized/broken bolts/studs,to assist in extraction. It will heat them to cherry red,same as an acetylene torch Used in tight areas where flame from a torch would cause collateral damage.
Got bearing out and pulled stator/rectifier/regulator/brusholder out.
Glass beaded cases,washed rinsed,dried. Sourced new bearings and brushes from Rockauto.
Brushes and drive end bearing correct,rear bearing was not.
They could not find the correct bearing as they were sending correct bearing according to their info.
I gave them rear bearing dimensions,still no good.

I found and purchased correct size bearing from an online rebuilder,sssembled and installed and worked fine for @ 45k miles when I removed it to upgrade my electrical system to a hand built hi amp FD frame alternator.

You may have some difficulty sourcing a new rectifier assembly,may have to settle for used and may have to buy a complete “used” alternator for parts to get one.

Considering what’s necessary to get alternator apart,source correct parts and then back together ,maybe a Reman could work for you.
Consider upgrading to an FC alternator,it puts out @ 70 amps to the SEs @60 amps. It is a direct replacement,bolts right in place and accepts field plug in back. Plug and play. Use your alternator for a core,they wouldn’t be able to tell difference from SE,FC alternator.
Don’t purchase cheapest one you can find,stay away from any Cardone rebuilt product=garbage.
AC Dellco has good quality renans as does Nippondenso .
You can get the Cardone part# for alt and shop around using that # at different stores for a reman. Lot of stores keep the same part# as rebuilder or the # is part of their stock# so you know if it’s a Cardone rebuilt.

Most logical path would be to replace iyours,use as a core and do the FC alternator.

Rockauto has AC Delco 2341757altermator for a 1988 RX7 TII for $60.79. They want $10.12 if you don’t send your core back. Best bang for your buck-you’d have 1/2 that in bearings,more in rectifier/used or new.

KansasCityREPU

iTrader: (9)

I hosed the rectifier up trying to take my alt apart myself to powder coat. Found a shop near where I work that rebuilds all sorts of electric motors, starters, alts, etc. I gave them the newly powder coating case and guts they they installed a new rectifier and brushes. Charged $60. Of course, I asked them to be careful because the case was powder coated so they gave it back and you could tell they put it in a vise and destroyed the powder coating. I took it back apart and re-powder coated. Now that I know how they come apart it's not hard.

Unless you can find a shop that can install a rectifier that can put out more amps than the factory I'd say go rebuilt and bypass a shop.

GSLSEforme

The 55 amp version that is on all non SEs and the 60 amp version on the SE do not share same construction and rectifier.

Fyi,the rectifier does not increase the amperage output of alternator. A stator with more windings is responsible for increased amp out put. On well built hi amp alternators,a larger stator with more/larger diodes in rectifier with a larger heat sink is fitted to case,which sometimes requires modifications to do so.

A lot of those low price hi output alternators for Sa,FB,FC and some FD alternators you see on eBay as well as other cars for sale touting double/triple output of oe alternator can only produce that at a high rpm and will actually charge less at low rpms/vehicle speed than oe alternator-when you need the extra oomph the most.
You never see any but short warranties on majority of them for the fact that you if you are using more than @70% of rated capacity, the larger amount of heat generated will destroy components,particularly rectifiers/regulators that like most other cheap rebuilders are tested and if found good are cleaned up and reinstalled in a glass beaded case with cheap bearings themselves that will fail from the heat of unit they are in. The only real new part will be a stator with increased windings.

While no two factory alternators will produce identical output,they will be relatively close. The cheap hi amp rebuilts,particularly the ones that charge less than oe at lo speed and need to be spun at 2k-@2500 rpm in order to develop Maximum amperage very often do not test at claimed output when tested at operating temp and often substantially lower on average of 30-40 amps.

Like everything else,there’s no free lunch. If you see an ad for a hi amp alternator for example,160 amps priced at @$100, you know it’s a piece of junk.
A quality builder of a 160 amp alternator that will actually charge@75 more amps than oe-at idle and all in by 1200 rpm will charge 3x that for an alternator because quality stators/rotors/brushes/bearings/heavy duty rectifiers/regulators are not cheap.

When looking for components to upgrade your existing alternator or building a larger case/larger output alternator or just buying a complete hi amp alternator with a good warranty,look no further than companies that serve fire dept and police vehicles. You can see how many extra lights are on ambulances in particular,same with police cars.
You see police cars at accident/construction sites for hours with ALL their emergency lights,radio equipment,computers,ac,etc running full tilt at idle speed. Heavy Duty alternators to handle that load and nuclear reactor like under hood heat indefinitely are quality units- they have to be or they wouldn’t have such fleet contracts. Spend your money,get what you want- with a decent warranty.

I buy all my specific alternator components online from manufacturers/distributors to companies that service fleets. Do enough business/shop around,you can find good stuff at reasonable prices-stuff you will not find in Napa catalogs or any auto parts store.

LongDuck

I found a Bosch (OEM?) part for 86-88 for a good price and sold as Mazda part. Will report back when received and listed as a 70Amp alternator according to specs, and new, not a rebuild. Thanks all!

t_g_farrell

iTrader: (1)

I got a quality new (reman I think) FC alternator and put that on my SA. It was plug and play (86-87 years I think, Mike will know). Really worth it.