Replaced LQ1 alternator, now something very strange happens...

[crazyd]

I get a full charge from the alternator for the first three minutes or so, then if I put the car in reverse or step on the throttle even slightly, the alt stops charging and goes to battery voltage. Tried swapping to another (new) alternator, still the same thing. I've gone over all my wiring and I can't see anything wrong, the grounds on the front and rear of the bellhousing are tight and no wires are touching anything hot. Then it gets weirder. If I shut the car off then start it back up, it's fine again for another three minutes. All this was fine before the previous alt went out.

 

This is a '95 with a CS-130D.

[Galaxie500XL]

Sounds like you're actually grounded through the motor mounts, based on prior experience...but you say the grounds on the bellhousing are tight...

 

I'd be tempted to run a temporary ground wire from the block to the body, and see if that makes a difference. if so, one of the existing grounds are crummy....

 

I get a full charge from the alternator for the first three minutes or so, then if I put the car in reverse or step on the throttle even slightly, the alt stops charging and goes to battery voltage. Tried swapping to another (new) alternator, still the same thing. I've gone over all my wiring and I can't see anything wrong, the grounds on the front and rear of the bellhousing are tight and no wires are touching anything hot. Then it gets weirder. If I shut the car off then start it back up, it's fine again for another three minutes. All this was fine before the previous alt went out.

 

This is a '95 with a CS-130D.

[crazyd]

it's funny you mention that, i was just thinking about trying another ground wire this morning. but isn't the alternator grounded through the timing cover where it attaches? where else would be a good place to run a ground wire like that? also, i timed it, and, it is almost exactly two minutes. i unplugged the backup switch on the tranny, but it wasn't lighting my backup lights either. i can literally shut the car off while going down the road, turn it back on, and buy myself another two minutes. this couldn't have anything to do with closed loop, could it?

Edited November 26, 2012 by crazyd

[Crazy K]

inspect the battery cables. I have seen wierd effects from a loose auxilary post, or a loose of corroded battery cable.

 

about that grounding, the ground in 94+ cars from the block to the body runs though the negative battery cable. make sure BOTH ends of that cable are properly grounded. Also make sure the positive cable is good at the starter, which is the joint between the alternator and the battery.

[crazyd]

i was thinking i might try disconnecting the O2 sensor and see what happens, but i just can't see how it could cause this...

[crazyd]

about that grounding, the ground in 94+ cars from the block to the body runs though the negative battery cable. make sure BOTH ends of that cable are properly grounded. Also make sure the positive cable is good at the starter, which is the joint between the alternator and the battery.

 

i have one end connected to the upper framerail next to the radiator, the other end goes to the front of the bellhousing with a half-dozen others.

[55trucker]

I get the impression that you may have a possible bad circuit where the field is concerned.

 

Have you confirmed that you do have only basic line voltage with a voltmeter at the battery when this occurs?

 

In your instrument cluster, does the *check gauges* lamp illuminate when you turn the key to on without starting the engine?

That check light is the *field circuit* path for the exciter circuit in the alternator, it acts as the alt warning lamp when the engine is not running but the key is on.

If the bulb is blown then the field exciter circuit cannot close (voltage is reversed thru that circuit when alt output reaches 12v+) when the engine is running and the alternator cannot begin to charge the system.

If the bulb IS good, then with the eng running, when the alt stops outputting a charge the *check gauge* lamp should light up, if you get no *check gauges* lamp when this occurs then possibly the problem is downstream in that circuit as there may be an intermittent open/close problem (possibly a worn wire or other that is causing a bad circuit).

[crazyd]

you've hit on an interesting point here, steve. because this is a '92 with a '95 engine and CS130D alterator, i had to adapt the harness to make this work on the exciter circuit. the short answer is i rigged a wire from the BAT terminal to the exciter circuit in the plug. it's worked for the last five years.

[Schurkey]

you've hit on an interesting point here, steve. because this is a '92 with a '95 engine and CS130D alterator, i had to adapt the harness to make this work on the exciter circuit. the short answer is i rigged a wire from the BAT terminal to the exciter circuit in the plug. it's worked for the last five years.

Subscribing.

 

I'd just love to convert my '92 to the CS130D alternator. The local Treasure Yard has a '95 LQ1 and transmission sitting in the dirt, getting rain and snow on it. Far as I know, I'd need the enormous accessory drive bracket from the front of the engine, the alternator, and move all the rest of the accessories--A/C and P/S--to the new accessory bracket.

 

What ducting does the 130D alternator have? Similar to the earlier LQ1? How about bracing of the rear part of the alternator--is it similar to the earlier LQ1?

 

Anything else you can tell me about the conversion to 130D???

[RobertISaar]

i have a LQ1 CS130D sitting here.... but the ducting is elsewhere and i have no idea if the bracket is similar yet.

[Garrett Powered]

when I upgraded I needed to machine off part of it to get it to fit the bracket. but it was for a 3.1

 

 

also needed to swap out a differently clocked case. special order part. LOTS of special order parts. to beef it up

 

you will love the cs130d. better in almost every way and even more so if you build one up.

[55trucker]

There are other alternatives to replacing the standard cs130 with a 130d on the early LQ1 (this does require extra curricular activity to make the *d* fit the early bracket), you could purchase the *iceberg* kit and upgrade your early 130 to improve it's output & overall longevity. This is the route I took when my *original* design alt failed (regulator) for the *last* time. I purchased the D17130 upgrade kit and reassembled the unit and back in it went.

The kit has done it's job, no more overheating the regulator or the diode pack due to the close quarters of the rear exhaust manifold, (of course, mine being a 91 I also have the piped in forced cooling air via the electric motor).

But the kit is a definite improvement, and it is worth considering.

 

 

http://store.alternatorparts.com/7130-cs130-series-iceberg-finned-alternator-upgrade-kit.aspx

[crazyd]

I documented my struggle with the conversion on my blog site here:

 

http://blogs.dohcfiero.com/?p=18

 

I wanted to do this upgrade as much for the CS130D as anything else. Yes, it was totally worth it, though it won't make you any more interesting in conversation. Doing it as a retrofit on a 92 motor is an enormous task because the whole timing cover/accessory bracket has to be replaced, and that means motor out and the whole front of the engine totally disassembled. But I did not do any additional ducting, there wasn't any to do.

 

However, I still need to solve my current problem, so maybe we can start the 130D retrofit discussion in a separate thread.

[Garrett Powered]

how is that not interesting? shit, that's awesome!

 

they make a self exciting mod for that alternator. it kicks on and starts charging when you rev the motor over, I think, 1500 rpm's. I took it back out once I got the right stator that has a 165amp rms output for my setup. the 190 would not charge at idle so we tried the self exciter for a minute and it didn't change nothing

[Schurkey]

I get a full charge from the alternator for the first three minutes or so, then if I put the car in reverse or step on the throttle even slightly, the alt stops charging and goes to battery voltage. Tried swapping to another (new) alternator, still the same thing. I've gone over all my wiring and I can't see anything wrong, the grounds on the front and rear of the bellhousing are tight and no wires are touching anything hot. Then it gets weirder. If I shut the car off then start it back up, it's fine again for another three minutes. All this was fine before the previous alt went out.

 

This is a '95 with a CS-130D.

 

 

However, I still need to solve my current problem,

Put an ammeter on that alternator output wire, tell me how many amps the alternator is throwing before the "three-minute time limit".

 

First Guess: alternator is over-charging, getting hot, and some protection circuitry is shutting it down. This ties in with the "three minute operation". I am not aware of protection circuitry in older alternators/regulators--but I don't know squat about the 130D. I know that some alternators have the regulator built into the ECU rather than stand-alone, or built into the alternator. I wonder if the ECU has the ability to shut the alternator off if it senses massive over-charging.

 

Second Guess: Failing belt tensioner. Any sign of belt wear? Any other accessories not working properly--P/S or A/C, for example? I say this based on you having problems when the RPM goes up.

 

Third Guess: Assuming that the ECU isn't playing games, and the belt tension is acceptable, I'd be probing the pins inside the alternator connector. What is happening at those pins at the three-minute mark? If the field coil is getting power...the alternator should be outputting. How does the field coil lose power? Since this problem has happened with two alternators, it does not seem to be an alternator problem--therefore must be somewhere else in the vehicle including the wire harness. If you put the vehicle in reverse, is the rocking of the engine/transaxle enough to pull on the wire harness enough to stress the harness?

 

so maybe we can start the 130D retrofit discussion in a separate thread.

NOOOoooooo! Keep it here where I can find it!

 

 

I documented my struggle with the conversion on my blog site here:

 

http://blogs.dohcfiero.com/?p=18

Nice write-up. I appreciate the alternator-connector rework. Do you have any photos of the bracket change?

 

I wanted to do this upgrade as much for the CS130D as anything else. Yes, it was totally worth it, though it won't make you any more interesting in conversation. Doing it as a retrofit on a 92 motor is an enormous task because the whole timing cover/accessory bracket has to be replaced, and that means motor out and the whole front of the engine totally disassembled. But I did not do any additional ducting, there wasn't any to do.

Are you saying the 130D does not use a duct like the earlier cars/alternators?

[Schurkey]

There are other alternatives to replacing the standard cs130 with a 130d on the early LQ1 (this does require extra curricular activity to make the *d* fit the early bracket), you could purchase the *iceberg* kit and upgrade your early 130 to improve it's output & overall longevity. This is the route I took when my *original* design alt failed (regulator) for the *last* time. I purchased the D17130 upgrade kit and reassembled the unit and back in it went.

The kit has done it's job, no more overheating the regulator or the diode pack due to the close quarters of the rear exhaust manifold,

I contacted the "Iceberg" folks a few years ago, they do not have an alternator housing compatible with the duct system used on an earlier LQ1. How did you connect the duct???

 

 

(of course, mine being a 91 I also have the piped in forced cooling air via the electric motor).

That's ALL NEW to me. Electric motor? Do you have photos???

[White93z34]

I always thought that duct was kinda dumb, Even most of the autoparts stores alternators I've gotten didnt have the spot for it to snap on. I've just removed them in the past, never suffered any ill effects because of it, hell I got like 100,000 out of an alternator without it before.

[55trucker]

The air pipe bracket is not by affected the redesigned *back housing* of the iceberg upgrade, it is held in place by a stud on the back of the housing and the air pipe slides into the round opening tightly pointing the end of the pipe directly at the rectifier assembly. This design was only used with the 91 model year, the motor that pumps the air in is located in behind the ECM, on the top of the frame rail hidden by the wheel housing splash shield from the bottom side & the coolant recovery tank from the topside. The motor is actuated by the secondary fan motor relay, but, in my case I have an aftermarket chip in the ECM and the secondary fan comes in at 195, much sooner than the 223 degrees that the OEM chip controls do.

 

 

 

 

That's ALL NEW to me. Electric motor? Do you have photos???

 

I don't have a photo currently of this arrangement, I suppose that I could take a couple for view sake.

Edited November 28, 2012 by 55trucker

[RobertISaar]

I wonder if the ECU has the ability to shut the alternator off if it senses massive over-charging.

 

a 95 won't, but a lot of the 96-up cars have the field circuit controlled by the PCM, which could shut it off. 95-down (except for some of the higher end caddy/3800 cars) have it connected to the ignition switch, so always on.

 

That's ALL NEW to me. Electric motor? Do you have photos???

 

i have an alldata diagram of it, if that might help.

 

The motor is actuated by the secondary fan motor relay, but, in my case I have an aftermarket chip in the ECM and the secondary fan comes in at 195, much sooner than the 223 degrees that the OEM chip controls do.

 

which means that it rarely ever turns on...... i can probably count the number of times my secondary fan has kicked on in the past 5 years on one hand. i would rewire it to come on with the primary fan.

[55trucker]

 

 

 

 

 

 

 

which means that it rarely ever turns on...... i can probably count the number of times my secondary fan has kicked on in the past 5 years on one hand. i would rewire it to come on with the primary fan.

 

If using the unmodded chip, one could do that, but I don't need to seeing as the secondary fan relay actuates at 195, the primary relay closes at 189, the engine thermostat is a 180. It is most useful when the car is motionless A/C on or off when no air is being forced thru the alt cooling pipe by the motion of the car to keep the alt cool.

[crazyd]

The belt is fairly new, the tensioner is tight and there is no evidence of belt slippage. I also took the alternator's plug apart and cleaned it thoroughly, then spliced on a new BAT terminal connector for the exciter wire to be sure. I am using the stock '92 ECM and MAP because there is no program for a '95 MAF with a 5-speed.

[Highmilagecutlass]

I like to double nut the auxuliary post / clean all of my grounds and add secondary ground from the engine to the body .

Also I tried some mod called the big 3 ? I added a secondary power cable to the battery from the back of the alternator to the positive side of the battery.

I heard some people go to the auxilary post with that extra cable . I truley suspect the aux post .

 

I hope this helps

[BrianK82]

What years got the electric fan for the alternator duct? I see that my 94' Cutlass LQ1 has the duct, but it is just open on the end that nestles between the trans and the oil pan, like it uses a low pressure area to draw in air similar to a cowl induction hood?

[Schurkey]

What years got the electric fan for the alternator duct?

 

This design was only used with the 91 model year, the motor that pumps the air in is located in behind the ECM, on the top of the frame rail hidden by the wheel housing splash shield from the bottom side & the coolant recovery tank from the topside.

The duct opening would ideally be in a HIGH pressure area, just like the opening for the cowl induction hoods.

[crazyd]

Okay folks, enough about the alternator ducting, I've got a serious problem I really need help with. I'm still no closer to a solution at this point. I've tried disconnecting the EGR, IAC, TPS & O2 to see if they have anything to do with it, and the alternator is still shutting down when I touch the throttle even slightly, once warmed up. This seems to be directly related to the ECM going into closed loop mode, but I can't think of any other reason for that to have an impact on the alternator.