Alternator weirdness

[Luvmeadeadpedal]

I got my car running yesterday after the previous owner let it sit for 3 + years and all seems well except for the alternator light.

The car shows just under 14v on the gauge and I put a meter on that battery terminals directly and reads the same. I turned on that lights, fan, ac and volt meter still read 13.85 colts so definitely charging.

Does anyone know at what voltage the light in the instrument cluster activates?

Now other factors to consider

I started the car still torn apart from blowing out the fuel line and swapping the fuel filter and the convertible top lid was propped open while I checked for leaks ( not that it would matter but who knows ) Could a loose battery terminal cause this?

Let me know if you have a thought here on this.

Next up I tackle refreshing the brakes.

[TorqueHorse]

Exciting that you got it running! I don't know that specific info, but here are some helpful bits...
1) The Manuals section (visible when logged in) should help you as you are putting the car back together. There is a service manual for the electrics that has info about the alternator and charging circuit.
2) Just from a quick reading I saw that it's 'normal' for the light to potentially show when idling.
3) In general, we are all battling bad earths with these fiberglass cars. So cleaning up earth connections (of which you can find where they are from the manuals) is always a helpful thing.

Good luck on the brakes too!

[Luvmeadeadpedal]

Hindsight is 20/20

I am no means a professional wrench but I have done jobs major (rebuilding a manual trans) to minor and have a reasonable idea of what I can do and what I should farm out to others. This is an alternator replacement and on any other car would be a 30 min job.

I scoured LEC and looked at a listing of alternate parts and ordered up a "remanufactured" alternator (2 year warranty) that was purported to fit the Impulse/Storm/Lotus online for $99 delivered.

Upon receipt I inspected the shiny new alternator and it looked to be the exact Nippon Denso alternator I just pulled out. The plug / location of the ground was in the same spot so I got to work trying to insert the alternator into the tight space between the drive shaft / A arm.

Recall this job is difficult to get the alternator out but the write ups on the LEC site are a good start. One note is that the hard pipe covered in foam is from the power steering system. I found it IMPOSSIBLE to get the alternator out without first draining the power steering (via vacuum pump) and then removing the front hose of the reservoir. It will make a mess and there is really no possible way to that I could to do this without this step.

You need this hose assembly loose to get the alternator removed from the engine.

Next when trying to remove the alternator from the space take loose hose / hard pipe assembly and get a nylon strap and pull it way up (way up) out of the way to get you the room you need to remove the alternator out of the small space.

TAKE A PICTURE of the orientation on the way out as it helps get you set for the return trip.

Difficult / messy with all the ATF (power steering fluid) all over the place but the alternator is out and you can breath a sigh of relief.

Here is where I made the my major FAIL. (FAIL-FAIL-FAIL)

I assumed the position basically hugging the brake rotor as you reach around behind it to make my attempt to install reman alternator. Before making the attempt I had a good look at my picture to get the orientation correct as it was tight on the way out and I was prepared for the worst on the way back in.

I spent a total of 3-4 hours over on 2 different attempts to get this alternator inserted back into the space and could not make it work. I had strapped tight the inboard end of the CV boot flat with another nylon strap. I removed bolts on the front suspension in order to get a little more ability to pry open the space. It was NOT happening no matter what I did.

It is a tough job in the best of circumstances and I was tired of holding a 10 pound alternator basically at arms length for hours. I felt utterly defeated. I had to step back from this as I was out of ideas on why this would not go back together and had to take a breath.

I fully removed the reman alternator and set it on the floor right next to the old alternator. You would look a them and say "those parts are the same" - same case, same back, same plugs - except it finally became apparent to me that they were not. The reman alternator is ever so slightly larger. Like maybe 8% larger and was never (NEVER!) going to fit into the space available.

Are you F'ing kidding me? Really? After all that grief I have the wrong part?

I felt at least vindicated at being unable to fit the reman alternator. I also felt dumb because I did not see this at the outset and wasted all that time. Lesson learned I suppose.

I did take the old alternator to a local shop who completely rebuilt the alternator with new parts for 2x the money of what I have already spent on the cheap reman alternator.

I finally got the original alternator back from repair and assumed the intimate position hugging the brake rotor / suspension assembly and guess what - it slipped right back into the space like it was greased with butter.

Please do yourself a favor and don't do as I did!

If you need to do this repair just take your alternator down to a local shop for a rebuild and it is guaranteed to fit back in there and save you hours of frustration.

One last tip - Getting the pivot bolt in is not bad but at the top you will have a bolt that slides along the slotted adjusting arm that that is nearly impossible to get started. My hands are not huge by any measure and I could not make this work. My 11 year old daughter (wrench in training) has tiny hands and it was impossible for her as well. It was in a twilight dream one morning as I was about to get up for the day that I had a moment of insight and figured out a way to successfully get this bolt threaded.

Take the bolt / split washer / flat washer and then put a reasonable sized zip tie tight against the flat washer. You will still have about 1" or so of exposed thread left. tighten the slotted arm and be certain that the slot is not blocking your ability to line up the bolt with the threaded part of the alternator using a mirror. Using 1/4 drive I was able to put some blue painters tape over the bolt and then in the socket to hold the socket in place. I was then able to use a U-joint then two longer 1/4 drive extensions lined up.

The bolt is now at 12 o'clock and the extensions are down and to the right at about 4 o'clock. Holding the zip tie you can just line it up into the threaded bit in the alternator and get enough turns on the ratchet to get it to thread. Then tighten the bolt it about 1/2 way and take a sharp chisel or screwdriver and cut the zip tie off and you can now tension the belt and and be done with this.

I am happy to say that "I won" but perhaps a bit of a pyrrhic victory with all the scars on my hands. If I would have just noticed the size difference at the outset I would have been much better off but I will NEVER make that same sort of mistake again.

Good luck!

[dapinky]

I feel your pain, having been there, done that!

It is documented on here that the Impulse alternator is 'slightly' larger than the Elan one...... and in fact, it's the other way round.....

....Lotus specified a smaller one than Isuzu used to solve the exact problem you found! (it's a 55A unit, not the 65A as used in the Impulse)

Although fitting into the space isn't an issue, and when being built, they are attached to the engine before dropping it into the car, it was soon found that there is no (easy) way to replace the unit on a fully built car.

I have just bought a recon unit for the Impulse from Rockauto, but to me it isn't a big issue as I have the suspension off the car, the prongeron is out and I will undo the engine mounting to change the cambelt..... so I can then shift the engine around a bit on a jack to get the new unit in........ and should I ever have to change it, I will drop everything out again.

I agree with you that a rebuild of the old unit is the best approach, but as mine is seized solid after 7 years of sitting uncovered in UK weather, I suspect the windings are swollen and a 'simple' rebuild won't be possible (last time I had it happen, it expanded enough to crack the aluminium casing).