Guys, I'm in need of your wisdom. My car refused to start a week ago and I found that the ground wire was not secured onto the battery post. A minor detail that the shop forgot. Luckily, I was able to push start the car and get her home. I recharged the battery and reinstalled it and all was fine...for about a week. The same thing happened. The car started very weakly in the morning. But as I was in a hurry for an appointment, I told myself to park where I can roll start the car. And indeed, I had to roll start the car. I then had a meeting at work so again, I parked where I could roll start the car. I drove maybe an hour to get to work. By the time I left work, it was getting dark and there was no way the car was going to allow any electrical activity other than just running the car. And it barely did that. It wouldn't allow me to rev above 3500 rpm. And every time I stepped on the brake, requiring electricity, there would be a loud backfire. As if that stroke missed a spark and the air/fuel mixture went out the exhaust unburnt. I finally aborted trying to get home as it became too dangerous driving on the freeway without lights at night. I got a tow to my nearest service station thinking I could just have them recharge my battery over night. In the morning, I would take the car to my mechanic to have the charging system looked over. But come morning, the service station said that all's fine. The battery holds a charge and the system is charging. Only not at idle. But once running, it's fine. I drove to work and all seemed fine. But I'm leary of the drive home tonight. This has left me scratching my head as to what actually happened to drain my battery. Also, shouldn't the alternator be able to supply all the car's electrical needs while running? Why then did the car drive so poorly? Also, I thought to get a battery tender after the last incident. But would having a battery tender mask the problems? If you always recharge your car overnight, how would you know if you have a charging problem? Thanks for any thoughts, Manny
Manny - tell us what your amp meter was doing...... Check the VW type fuse and the large 60-amp fuse on the firewall. Are they intact? I await your reply. Jim S.
Jim, I'll be working late tonight so I won't keep you up. I've noticed that my amp meter didn't register any change this morning on the drive to work. It sits pretty much in the middle. Maybe just a hair to the negative. But it doesn't move. Now I recently used the AC for the first time. And noticed the amp meter swung negative and stayed there. Regardless of how fast the engine is turning. There was no change in the reading until I turned the fan off. I'll check the fuses when I get home tonight. I recently had the gauge sent out to MOMA to have it rebuilt. It should be a new unit. Just had a thought Jim. Might this have to do with your reply to my burnt toast comment a while back?
Which ignition box are you using? I had an original AEC-103 that was squirrely like this; some days it was temperamental, others it was great.
Jim, As I drove home tonight, I noticed as soon as I turned on the headlights, the amp meter registered negative. If I had to guess, it was about -5. This never changed on the drive home. The lights in my gauges, slowly faded out. I did make 2 stops. One to Pep Boys for a trickle charger. And another for dinner. Both times, the car started without issues. When I got home, I checked the VW type fuses and all are fine in the front compartment. I tried looking for the firewall fuse and I can't find it. I don't think I have one. Or someone has relocated it. Should I be able to find it from the top of the engine? Or do I need to get under the car? Scott, What ignition box are you asking about? I haven't a clue what you are asking. Also Scott, where exactly are you standing when you took the following picture? I can't locate my firewall fuse box at all. And how has your modification held up to the heat in the engine compartment? Image Unavailable, Please Login
Manny: I don't think that a trickle charger is going to help much if the battery is undergoing severe discharges. Trickle chargers typically use a low-amperage output (along with "smart" voltage-sensing circuitry) to maintain healthy batteries through periods of storage and disuse. They don't have enough juice to bring back a discharged battery. My $0.02. Dan
1) The ignition box is in the rear trunk, passenger's side just forward of the side marker light. Should look like this assembly mounted on the rear interior fender well: http://www.dinorestoration.com/reassembly/pages/Reassembly217.html I was thinking that your running issues were similar to mine when I had the Marelli AEC-103 ignition box perform a soft failure. Sometimes it would work, sometimes not. If you had a modern unit (MSD, Allison,ect) then we might be able to rule that out. 2) I was standing in the passenger's side, rear wheel well looking forward - the wheel was off and the splash panel removed. The fuse box is mounted just forward of the engine on the vertical wall that separates the engine compartment from the passenger compartment. The fuse has worked well, no problems so far. Hope this helps.
AH HA! So it's not viewable from the top of the engine. Thank you very much Scott. I'll check this fuse this weekend. Also, I'm running Permatune for my ignition. I'm probably getting oil on my alternator as well. I tried locating your post about your modifications to the heat shield but came up empty. Might you point me to it? Thanks again, Manny
Manny - I do not believe that your ignition box (Dinoplex) is the issue. It simply won't work at all when the main system voltage drops below a critical value (perhaps around 10 volts). If the Dinoplex stops working, the car stops running. Furthermore, your system is not discharging excessively,,, it is discharging appropriately. The problems results from the system not charging the battery. You can run for a finite period before you drain the battery (lights, fans, ignition, etc.) to the point that nothing works. That your amp meter discharges at least suggests that you have proper continuity in the charging circuit. It also suggests that you are not charging...hence either the voltage regulator under the dash is malfunctioning or the alternator is not working. If the firewall fuse (16 amp) is open (blown), then the alternator will not receive field current from the regulator, and consequently will not produce current output (won't charge the battery). Check the firewall fuses. I suspect that they are okay. I have never seen one blow. If they are okay, then you must trace the problem between the regulator under the dash (red box) or the alternator. If the amp meter was recently out, perhaps one of the leads on the red regulator box came loose. There should be 3 leads (Plus, minus, field). Let us know what you find with the firewall fuse. Also, there is a regulator fuse under the forward bonnet (which you said was okay). You might try rotating all of the fuses to make sure that they are making good contact. If the fuses are okay (firewall), then we can discuss the next step. Jim S.
Jim, Thank you very much for your suggestions. I'll check things out this weekend and report my findings. Thanks again everyone, Manny
Apologies as I thought this was a driveability issue (limited to <3500 RPM) and it appears to be a charging problem.
Jim, Am I wrong in thinking that it's the alternator that runs the car once it's been started? That's why alternators are spec'd at a certain amperage, right? To make sure it outputs enough to cover all the systems in the car? So even with a dead battery, if the alternator and the charging system is working, then one should be able to push start the car and drive long enough to recharge the battery, right? If that's correct, then what I experienced that night on my attempt to drive home should have pointed to a faulty alternator or regulator. All the systems in my car were definitely not supplied with sufficient electrical power. And yet, my local service station says she's charging. Anyways, I've been playing with my boy all day so I'm wiped out. And I haven't had time to play with the car. I should have some findings by the end of this 3 day weekend. Scott, no apologies needed. You guys teach me so much here. All replies are welcome. Thanks again and have a great weekend guys, Manny
Manny - years from now you will remember playing with the kids, not disecting an electrical gremlin in your car. Enjoy the kids first, then play with the car. Your car can run without an alternator....it cannot run without a battery. Does this answer your question....? The battery is the source of current to your electrical system. Think of it as a swimming pool with a pipe at the bottom that allows water (current) to flow to your various loads (lights, ignition, capacitive discharge system, horn, etc.). The alternator is a hose filling the pool from above. If you turn off the alternator, you will have sufficient stored water (current) to maintain operation for a while. Once the pool level falls below a critical level, you will no longer have sufficient pressure (voltage) to push the remaining current (water) to the loads. All current produced by the alternator first runs through the amp meter on its way to fill the battery. All current leaving the battery, likewise, runs through the amp meter on its way to a load. The amp meter reflects the net direction of current flow....either to the battery (charging) or away from the battery (discharging). When the meter reveals negative current flow, the battery is supplying current to the car. When in the positive half, current is flowing into the battery (charging). There are normal situations where the battery will discharge. For example, when at idle, in the rain (wipers), at night (lights), with radiator fans running, the alternator simply cannot provide sufficient current to run these electrical loads (low RPM...little alternator output). The reserve water in the pool makes up the difference, and the amp meter reveals a discharge state. When you move away from the traffic light, the alternator produces sufficient current to supply the loads AND has excess current to top off the pool (charging). It is the job of the regulator to sense when the pool is full and turn off current from the alternator so as not to over fill the pool (over charge and boil off battery fluid). If your amp meter is discharging I cannot understand how your local service stations says that your system is charging. For the moment, all diagnostics rest on the status of your amp meter. Does it every go positive? If you have charged the battery overnight, and the pool is full, then when you start the car you may see zero charge. It you turn on a number of loads, such as lights and ventilation fans, you should see a discharge. After a few moments, raising the RPM to 1500-2000 should reveal charging (replacing the water drained out of the pool). Hope this makes sense. Jim S.
Jim, Thanks for setting me straight. I was really surprised when the service station said that my system is charging. I was still showing a discharge while driving. Anyways, I just passed my trickle charger in the garage and noticed it wasn't charging. So I'm assuming I have a full battery. I'll see what the amp gauge reads later. Thanks again, Manny
Manny, With the help of a couple of visual aids, I'll point out some reference points on my Tipo E to help ya spot the fuse holder..."from the top." At the upper edge of my first shot, locate the right hood hinge, then look just to the right of it & you'll see a somewhat faded red wire next to a white wire. Follow those two wires ever so slightly down to the fuse box (hiding behind the errant fuel tank vent hose). You can see where they are attached to the bottom of the box, too. In the second pic, I figured out how to circle the fuse holder! It's still fairly visible with the air box in place; ya just gotta know where to look. Now, jumping back to Scott's close-up, check out the lower left side of the pic. You see an end cap on the cam cover/head instead of a breather. His engine apparently doesn't have a 'snorkle' on the forward bank. 'luck with the fix. Coop Image Unavailable, Please Login Image Unavailable, Please Login
Coop, Thank you very much for those pics! That helps a lot. Unfortunately, I don't have a fuse block there. There's nothing there but the holes that the block should be mounted with. I'm going to have to call my mechanic today and ask about this. As things tend to happen, I was not able to do anything this weekend with the car. I hope to find some time during the week. Stay tuned, Manny
Manny - there are two wires leading to the alternator. They must come from somewhere. It is difficult to visualize the back of the alternator from above, but try to see where the two wires exit the area of the alternator. Someone likely installed an in-line fuse on both. One is a heavy gauge white wire, the other a very heavy gauge red wire. There is a third, smaller wire that controls the air-pump clutch (brown/black). Ignore this. Jim S.
Jim, I had the same suspicions about the in-line fuses. I was going to start at the alternator and follow the wires as best I can. Thanks, Manny
Hi Guys, I finally got around to this. And it appears that I have no fuse coming off of the alternator. How bad is this? I was lucky enough to have access to a working voltage regulator and tested that. And have concluded that my alternator is the culprit. She needs to be rebuilt. I have a bit of oil that gets on the alternator and I'm assuming this is the cause of my problems. I haven't been able to find the post that shows a modification to the heat shield to prevent this problem. If someone could be so kind as to point me in the right direction, I'd be greatly appreciated. Thanks again for all your help, Manny
Very bad. Could result in fire or worse, a false sense of security. Oil drops onto the alternator and shorts the system but not all at once. The wiring loom could be stressed and insulation melt causing multiple failures. Use a modern 60AMP fuse/holder you can get at any high end car stereo shop for $20. PS - I'm working on an inexpensive Bosch upgrade to the alternator. If your rebuild is going to cost big bucks, this future information might be a helpful alternative.
Scott, I was going to do what you had done. Going with the modern 60AMP fuse from a stereo store. Thanks for alerting me to the possible dangers. I'm really swamped right now so I'll continue with the trickle charger until my time frees up. So I won't be pulling the alternator for a bit. What's the timeframe on your Bosch alternative? Thanks, Manny
Timeframe is immediate. Pls contact me offline for the secret tribal information before I get voted off the island. LOL Seriously, I'll bet I get this resolved before you work the contortionist remove of the alternator w/heat shield - that motion is something I don't wish on anyone. Too bad it didn't happen in late July when we were in West LA with "Il Maestro" Carlo Durante who can do this with his eyes closed. BTW, you're the ninth person in a year or so who have had the dreaded alternator meltdown, so don't feel bad. I even mod'ed my heat shield to add a "sloping hat" that anticipates oil drips and channels them off the back side. This failure mode is common with several series of Dino follow on engines, including our F355 brothers so don't feel like you're alone. Scott
Scott - you piqued my interest. What is the simple solution? If it is related to oil and gravity, it is the brushes that cause the problem. The carbon gets oil soaked and short across the armature, or lead to high resistance and poor output. Removing the brushes and cleaning, as well as wiping down the armature with a cloth soaked with brake-clean will solve the problem. It is unlikely that a diode went bad. Nonetheless, getting the brushes out while the alternator is installed is a challenge, to be met only by those with small hands and great patience. Jim S.
