Alternator without Mazda ECU? - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


MEGAsquirt A place to collectively sort out this megasquirt gizmo

Reply
 
 
 
LinkBack Thread Tools
Old 04-13-2007, 03:14 PM   #1
Newb
Thread Starter
 
Join Date: Jan 2007
Location: Rijeka, Croatia
Posts: 9
Total Cats: 0
Default Alternator without Mazda ECU?

Hi,

Few days ago I finished MS fuel & spark control for my friend's 2001 NB 1.6 turbo Miata - btw, it goes very well , even with "raw", unfinished fuel/spark maps and low boost, can't wait 1 bar boost

But now I have stupid problem with alternator - it doesn't charge battery because it was previously controlled by std ECU which is now dead, and MS is in its place now

I already tried many combinations, but all went without sucess - I took two thin wires (grey-red and grey) and connected both to +12 V - alternator started charging battery but with enormuous whining, white smoke and cloud of rubber particles from desintegrating alternator belt...I suspected that maybe it was problem in alternator belt itself (which is btw slightly too long) but my friend said that he hadn't such problems when std ECU was alive & kicking ...although belt is too long , it seems that tension is OK - it isn't too tight or too loose - it seems just right...and without two thin wires connected - it doesn't whine at all...but of course it doesn't charge anything neither

So what to do?

Anyone had such problems with his Megasquirt install?

Is there alternative alternator bolt-on replacement, that doesn't need ECU control?

Obviously putting OEM ECU and connecting it just as "alternator piggy back computer " is out of question due it's sudden and tragic death - any other idea no matter how strange or funny sounds will be welcommed ,hmmm I am out of ideas for this week...
Bubba Zanetti is offline   Reply With Quote
Old 04-13-2007, 03:22 PM   #2
Elite Member
iTrader: (13)
 
cjernigan's Avatar
 
Join Date: Oct 2006
Location: Atlanta, GA
Posts: 8,147
Total Cats: 6
Default

The NB alternator is heavily controlled by the stock ECU, that's why we do parallel installs on top of A/C control and things like that.

I'm pretty sure you can use an alternator from an NA 1.8 and there is a different switch that activates it. Someone else will have to confirm that though.
cjernigan is offline   Reply With Quote
Old 04-13-2007, 07:28 PM   #3
y8s
2 Props,3 Dildos,& 1 Cat
iTrader: (8)
 
y8s's Avatar
 
Join Date: Jun 2005
Location: Fake Virginia
Posts: 19,038
Total Cats: 407
Default

it can be controlled externally. Jason C made me a little circuit (he loves circuits) that measures system voltage and outputs a PWM signal to the alternator as feedback to keep it around 13-14 volts. Post on .net and ask him about it.
y8s is offline   Reply With Quote
Old 04-13-2007, 07:44 PM   #4
Ben
Supporting Vendor
iTrader: (33)
 
Ben's Avatar
 
Join Date: Jul 2006
Location: atlanta-ish
Posts: 12,689
Total Cats: 99
Default

Use an NA alternator.
Ben is offline   Reply With Quote
Old 04-13-2007, 08:16 PM   #5
Elite Member
iTrader: (13)
 
cjernigan's Avatar
 
Join Date: Oct 2006
Location: Atlanta, GA
Posts: 8,147
Total Cats: 6
Default

Do the NA alternators have an internal circuit that measures system voltage in order to activate or is there an external system that goes with it?
cjernigan is offline   Reply With Quote
Old 04-13-2007, 09:18 PM   #6
Ben
Supporting Vendor
iTrader: (33)
 
Ben's Avatar
 
Join Date: Jul 2006
Location: atlanta-ish
Posts: 12,689
Total Cats: 99
Default

NA is internally regulated
Ben is offline   Reply With Quote
Old 04-13-2007, 09:21 PM   #7
Elite Member
iTrader: (13)
 
cjernigan's Avatar
 
Join Date: Oct 2006
Location: Atlanta, GA
Posts: 8,147
Total Cats: 6
Default

Good to know. Thanks man.
cjernigan is offline   Reply With Quote
Old 04-14-2007, 12:44 AM   #8
Newb
Thread Starter
 
Join Date: Jan 2007
Location: Rijeka, Croatia
Posts: 9
Total Cats: 0
Default

2 y8s:

Tnx, that's what I wanted to hear!

So is "JasonC SBB" from this forum man I'm looking for?

If it is , unfortunately he hasn't any e-mail adress in his public profile ... and I'm not sure how to contact him ... do you maybe have his e-mail or some other contact info?

Last edited by Bubba Zanetti; 04-14-2007 at 09:15 AM.
Bubba Zanetti is offline   Reply With Quote
Old 04-14-2007, 04:48 AM   #9
Supporting Vendor
iTrader: (10)
 
Reverant's Avatar
 
Join Date: Jun 2006
Location: Athens, Greece
Posts: 5,440
Total Cats: 198
Default

Just a tip, here is what the PWM should look like at idle:



Scales are at 0.5V/div and 2.5ms/div.

Jim
Reverant is offline   Reply With Quote
Old 04-14-2007, 09:25 AM   #10
Newb
Thread Starter
 
Join Date: Jan 2007
Location: Rijeka, Croatia
Posts: 9
Total Cats: 0
Default

2 Reverant:

Very interesting, so alternator field current is PWM controlled by ECU, from your waveform picture it looks like cca. 1.6 V @ 40% duty cyle on idle, and I conected it directly to 12V DC - oouchh!!!

...but the question is - is there a way to made relatively simple circuit to simulate oem ECU control in all conditions, not only at idle ?

Or even better - if two thin wires are directly connected to coils inside alternator , maybe I can use external voltage regulator from some other alternator ?
Bubba Zanetti is offline   Reply With Quote
Old 04-14-2007, 09:53 AM   #11
:(
iTrader: (7)
 
Join Date: Jul 2006
Location: nowhere
Posts: 8,281
Total Cats: 2
Default

easeist thing would be a internally regulated alternator from a earlier car. Get some more posts up and then PM jason your question.
magnamx-5 is offline   Reply With Quote
Old 04-14-2007, 11:18 AM   #12
Elite Member
iTrader: (9)
 
Join Date: Aug 2006
Location: Concord, North Carolina
Posts: 4,173
Total Cats: 5
Default

Wow, wait. So I don't have to worry about the ECU controlling the alt. on my 90 because its self regulated? And since AC/PS is out...I COULD just run MS?
miatamania is offline   Reply With Quote
Old 04-14-2007, 12:52 PM   #13
y8s
2 Props,3 Dildos,& 1 Cat
iTrader: (8)
 
y8s's Avatar
 
Join Date: Jun 2005
Location: Fake Virginia
Posts: 19,038
Total Cats: 407
Default

Jason C SBB on miataforum.com will have the info you need... he's not active here.
y8s is offline   Reply With Quote
Old 04-14-2007, 01:10 PM   #14
Ben
Supporting Vendor
iTrader: (33)
 
Ben's Avatar
 
Join Date: Jul 2006
Location: atlanta-ish
Posts: 12,689
Total Cats: 99
Default

Quote:
Originally Posted by Bubba Zanetti View Post
Or even better - if two thin wires are directly connected to coils inside alternator , maybe I can use external voltage regulator from some other alternator ?
Why do you insist on doing things the hardest way?

Quote:
Originally Posted by Ben
Use an NA alternator.
Ben is offline   Reply With Quote
Old 04-14-2007, 02:00 PM   #15
Newb
Thread Starter
 
Join Date: Jan 2007
Location: Rijeka, Croatia
Posts: 9
Total Cats: 0
Default

2 Ben:

Unfortunately , the hardest way is to mount old-type alternator from NA Mazda - I know that from your point of view you is hard to believe (large quantity of Miata spare parts in U.S.) , but in Croatia there are very few NB Miata's, let alone NA models ... so to find such alternator is very, very hard - almost impossible.


So, electronic device will be the most elegant solution momentarily - afterall alternator is already mounted and working , I just need convinient way of regulating field current.
Bubba Zanetti is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Raleigh: Fiberglass headlight scope, 1.6L ECU, AFM, Hardtop latches, more bigmackloud Miata parts for sale/trade 13 09-22-2017 01:34 PM
1994 Spec Miata Race Car SM/SM2/SSM For Sale Quinn Cars for sale/trade 6 10-23-2016 08:58 AM
Back to Stock Part Out!! Turbo Parts, MS2 Enhanced 01-05, Suspension, and MOAR! StratoBlue1109 Miata parts for sale/trade 16 10-02-2015 10:39 AM
Are my coils failing? viriiguy General Miata Chat 5 09-28-2015 08:39 PM
Another Alternator thread ihiryu General Miata Chat 9 09-28-2015 11:22 AM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 02:36 AM.