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backinbrat

original Alternator output

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hi there everybody, im fairly new to this fourm and this is my first post/thread whatever its called!

 

I was wondering if anyone could tell me the original output of an EA81 alternator as im draining my battery (which is only a year 1/2 old and seemed to work fine before...) I have all the usual bits working (lights, engine elctronics etc) but now i have a CB radio and a 25watt pioner tape player (which is actually quite good! to my suprise) and i have 2 55watt hella 550 compacts, and with these my juice rate is not keeping up, and im wanting to put 3 more lights on it, big ones, is this just because im not createing enough power or is it because its dischargeing slightly? if i hold it at about 4000rpm (its a guess, the UK specs dont have a rev counter) then it will just keep up. whats my problem? thanks all!

 

Tom :D

Sussex, UK

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Hello.

You probably need a bigger alt, I think ea81s push about 40amps if you are lucky. You can swap a GM Alternator in there with MINOR modifications...it'll push 100amps.

 

Read up...here

 

Good luck man.

 

Justin.

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Ah, you see i might have a problem, do you class a GM alternator as something american, like a chevy one or somin or do you class that as everything, as vauxhall is part of GM, because getting hold of the US stuff over here aint easy and its expensive, but thank you for the info and advise, i shall search for something that could fit, and something with that power output, and i can always make up some braketery to attach it, cheers!

Tom :D

Sussex, UK

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GM-USA cars, built in the USA. Large engined Chevrolet/Caddilac/et al from the 1980's is the popular ones.

 

Not to many of these running around the Sussex countryside??? :rolleyes:

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LMAO! :lol: no, not many of them! though some of them are nice, like the old corvettes and cameros, and one of my favourite the el camino (obviously after subarus) I did know a guy with a corvette stingray but things like that they guzzle too much gas really, with 95 oct unleaded floating around 95p-£1 a litre, which in nearly $2 (U.S) you can see why we dont have too many V8 machines over here, although my step dad does have a grand cherokee! (yes a striaght 6, i know!) things over here mostly with V8's are range rovers, you do get the occasional proper V8 machines, and sometimes a hotrod, and im talkin USA hotrods here, model T's with funking great lumps in them! but my dad does have a ford anglia with a V6 in it, white with blue flames. :headbang: anyways im drifting off the subject here, looks like im gonna have too make up some custom braketrey, but i do have a friend who might have an SVX alternator or something beefery than standard, but at least i know what im aiming for, cheers everyone

Tom :D

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Does anyone know if there is a meathod of testing amp output?, i was thinking an ohm multimeter but not sure if thats just volts.

 

~Dayten~

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Does anyone know if there is a meathod of testing amp output?, i was thinking an ohm multimeter but not sure if thats just volts.

 

~Dayten~

 

Most battery testers will work... w/ the car running it should be putting out 14+v but I have no idea about amps.

 

I dont think something is quite right, check and clean all your grounds and stuff and belt tension. I can run my 200w stereo very loud with my highbeams on(I have the 4 beam setup) along w/ 3 55w halogen lights and 1 100w light and maintain a charge at idle. Although as soon as I shut the engine down my battery dies completely in about 3 minutes if I leave everything else on.

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Ignorant (literal meaning) question: What do you have for auto parts supply stores? (Hopefully that translates well into the Queen's English, what with our "common language" and all! :grin: ) Can you source US parts locally, and not for a King's ransom??

 

(OT again, but a friend visited the UK a few years ago, and people were in disbelief that his daily driver had a 7+liter engine. :eek: )

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Most battery testers will work... w/ the car running it should be putting out 14+v but I have no idea about amps.

 

I dont think something is quite right, check and clean all your grounds and stuff and belt tension. I can run my 200w stereo very loud with my highbeams on(I have the 4 beam setup) along w/ 3 55w halogen lights and 1 100w light and maintain a charge at idle. Although as soon as I shut the engine down my battery dies completely in about 3 minutes if I leave everything else on.

 

 

a 200w stereo system does not necessarily draw (200/12=16.666) 17 amps.. hate to be the jerk to point out when you are quoting the total power draw of your entire system.., so i may be wrong, but if youre using speaker wattage to determine that number that means nothing :lol:

 

to my understanding the XT6 alternator was like, 90 or 95 amp, and it was a relatively simple swap.. if you do upgrade the alternator you may also want to consider installing a new, larger gage wire (if needs be) in place of the stock connection between alternator and battery. the original wire WAS only built with the stock alternator output in mind (~40 amps was it?) and with 90 youd be doubling that, so may as well play it safe.

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EA81 stock: 55A max.

EA82 stock: 60A max.

XT6 stock: 90A max.

All of them will fit your car; I believe you'll have to change the pulley on your XT6 alternator to fit the belt.

 

Just a thought, check the current draw out of the battery with an amp meter and the ignition off. It could be that you have something else draining the battery. Will your battery hold a full charge? Lastly, it could be that you don't drive enough to put back what you took out of the battery starting and running for short periods of time.

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hey!!! im going to try a PM or two, but I'll try for the thread-jack, too...

 

regarding the GM alternator conversion.. there is a similar conversion for the Datsun Zcar... and ive been wondering if A its the same GM alternator (havent done my datsun research lately) and B if the bloody stock alternators (datsun vs soob) are physically the same, as far as mounting. I am fairly cerI dont live near any of my datsuns/parts, and I only have my one subaru.. but could one of you guys out there who play with datsuns and soobs maybe check the alternators out, see if they might be swappable? because if thats the case I will start buying every XT6 alternator i can lay my hands on in the JYs..

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