Alternator question

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What Lexus is it as I'm sure their alternators have a freewheel clutch?

It's Lexus IS250 2.5L petrol. Yes it definitely has a clutch pulley but the replacement was marketed as a replacement for it and also has some sort of clutch pulley too OAP I think as it's pulley is covered by a cover.
 
I think this is the Lexus/Toyota part No 27060-31050
The original will be Denso.
It will have a freewheel clutch. (I hope the belt is on correctly)
 
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Oh dear I am so much behind the times, last free wheel I saw was on a three brush dynamo. You turned the ignition on and the dynamo motored then started engine and then adjusted 3rd brush to get required output. At the same time as adjusting ignition timing etc.

Can't remember what year that was, but well before the Morris Minor was invented.

The early Japanese cars had mechanical voltage regulators, not electronic like Lucas, and not built into the alternator, it seemed to be a step backwards, we were getting use to having an integral charging device, and the old RB106 regulator was a thing of the past, and then the Japanese cars arrived.

Early Lucas 11AC alternators did have TR4 regulator, 6RA relay and 3AW warning light control, or the 16 RA, but once the ACR range arrives we lost all the little boxes.

The Delco has same mountings as Lucas even same three connector plug, I remember the little plastic pin needed to assemble the Delco that held the brushes in.

Also the French single phase alternators, were it seems designed to be cheaper to make, but cost more to buy, and warning light always glowed a little.

However we have always had versions with fuses
inside-rug11.jpg
you can see the lead fuses here, and this regulator goes back I think 1930's nothing new under the sun.
 
So I have an update on this now. My new Denso branded alternator arrived. I inspected the Denso one and if i stopped the turbine blade with a flat head screwdriver and rotated the pulley counter-clockwise it spins doing the job of the freewheel clutch. So then I took out the aftermarket one and did the exact same test to try and rotate counter-clockwise and the pulley just doesnt move so means the clutch mechanism isn't working. Then I got out my Digital Multimeter and put it on continuity and did a test between the body of the alternator and each of the 4 pins on the 4-pin connector (IG, RLO, L, M) and the mutlimeter kept beeping giving a continuity between the body and each of those pins. I did the same test on my old original alternator and it only beeps on 1 of the 4 pins. Then I did the exact same test on the brand new Denso one and exactly same as my original one. It only beeps on one of the pins. But this unbranded aftermarket one keeps beeping on every pin.

Anyway then I installed my new Denso alternator. I inspected the belt and not a single bit of damage on the belt. The belt is still brand new looking. After I installed the new Denso, i measured the voltage of my battery and it was reading at 12.5V. Then I connected the negative terminal back up and measured the voltage again. It had dropped to 12.3V which i'm assuming was the cars electronics initialising and the door lights that came on.

So then I went to start the car, and it started perfectly and absolutely normal sound just like my original one. I measured voltage at the battery once it was running, and it was reading 14.5V, then I put max load on it by putting heating fan to full, high beams on, hazards on, heated seats on etc and I measured the voltage with those loads and it dropped to 14.1.Then I took car for a drive and after I got back everything was fully warm I did another voltage read and it read 14.01. Are these within normal voltage parameters?

Oh and one other thing I forgot to mention last time with that previous noisy smokey startup, when I started the car it seemed like it really struggled with battery power, exactly like when battery is low and you just about have enough power for a crank. But I was thinking how my battery could have been low because it was a brand new battery only few months old and I had left the negative disconnected over the days when I was working on the car. So today when I put the new Denso one in, I was expecting battery to possibly be flat but surprisingly battery was full of power and car turned over perfectly normal without any hesitation. So, i'm thinking that might have also had something to do with that rubbish alternator?

Thank you all for your help and advice.
 
Your voltage parameters are just fine, achieving 14v with a full load is exactly what you want to see.
I think the original alternator has been a real dog and responsible for all sorts of nasties!
A job well done.
John :)
 
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