Gene

Hi Robbie, Can't say I understand this completely, but the first thing to check is the ground connection for the rear bulbs. If the ground is weak, all sorts of unusual symptoms occur. Changing the bulb may have disturbed the ground connection to start all of this. Hope this helps! Gene

Can you borrow a battery from another vehicle as a test? Gene

Hi GeorgiaJeeper, Did you get a new battery too? If not can you at least take one of your batteries in to be charged and tested? It really sounds lie a bad battery to me. And, as above, a bad battery can overheat and damage even a new alternator. Good luck! Gene

http://store.alternatorparts.com/7140-140amp-cs130-series-iceberg-finned-high-output-alternator-upgrade.aspx http://store.alternatorparts.com/cs130i-a105-amp-iceberg-series-finned-housing-alternator.aspx links to Iceberg alternator Gene

One more comment on weak batteries.... At least my 88 uses a GM CS130 alternator, not sure about other years. The CS130 has high output in a small case, so heat is a big problem. The harder the alternator works, the more heat it generates, which can damage and burn out the rectifier and diodes. So to use the alternater to charge a dead battery, or to try to "get by a while longer" with a weak battery can kill the alternator. Too much heat damaging components. Yeah, I know we have all done that and gotten away with it, but it is hard on the alternator. About 15 years ago, after going through several alternators, I found an "Iceberg alternator" with cooling fins. Still going strong 15 years later! I will try to find a link. Gene

If anyone wants a laugh: My story about running a car without the battery: Decades ago, I was going to school in Philadelphia. I drove an old Pinto, standard transmission. I parked a block or two off North Broad Street, in a fairly bad neighborhood. One day I didn't get out to the car until after dark, noticed the dome light didn't go on when I opened the door, thought "burned out bulb". Until I put the key in the ignition and turned it, absolutely nothing. I thought "dead battery". Until I opened the hood, when I saw "no battery". Someone had taken bolt cutters to the cables and taken the battery. So I was a student, had no money, and the car was in a bad neighborhood. I didn't want to leave it there overnight. So I stripped about an inch of insulation off each of the cut cables, called a friend, and used jumper cables from the friends battery to the cut off cable ends. The car started and ran. No battery. This was a standard transmission. If I stalled it, I would have absolutely no way to restart it. So I drove about 5 miles down Broad Street, at night, hoping and praying, babying the clutch, to get home. It worked! Gene

Absolutely agreed, don't pull the battery cable as an alternator test. The battery acts to stabilize the voltage in the system, if there is any voltage peak or surge, typically the battery will dampen that out. Without the battery, risk of damage to electrical components is much higher. A surge may occur when the battery cable is disconnected. If you want a really quick, semi-accurate alternator test, with the engine running put a screwdriver or steel wrench near the backside of the alternator case, toward the center. Typically, if the alternator is working, a strong magnetic field is created inside, and it will attract the iron or steel. Another test that may be useful in cold weather. An alternator generates heat when it's running. If the rest of the engine is relatively cool, a working alternator case should be warmer. Of course, if the engine is hot, this test would not be useful. However, you can get a cheap voltmeter or multi meter for about $10. There is no excuse for not having one of these for testing! Gene

Hi Newton, Check the ground connection for the rear lights. If the ground is defective, the electricity will try to "double back" through the second filament. Good luck! Gene

Hi GeorgiaJeeper, Electrical problems can get confusing. Consider some basics: 1. For a vehicle to run, it generally needs at least 9 or 10 V available. This can come from a battery, or from an alternator. A vehicle can run on battery power alone, with the defective alternator. A vehicle can run on alternator alone, with the battery removed. 2. However, if the battery is very very low, it can "suck up" all of the alternators output, especially if the alternator is weak. 3. Do you have, or can you get a battery charger? Charge up the better of your batteries, if the charger output is relatively low output, this may take several days. After the battery is fully charged, disconnect the charger, let it sit for an hour, and then check voltage at the battery. A good battery will have about 12.8 V. 4. You can't really depend on the alternator to charge a fully discharged battery. It would take several hours, at least, of engine running above idle to fully charge a totally discharged battery. 5. As stated in another post, with a fully charged, good battery, a good alternator will typically raise the system voltage to around 14.4 V. It doesn't have to be exactly this. The voltage will be lower at idle, and may increase if you rev the engine. The voltage will be lower with a significant electrical load, such as headlights being on. Why don't you try the above, especially with the fully charged battery, and see how things check out? My guess is that ALL the batteries are very bad, and "eating up" all of the alternator output. Good luck! Gene

Thanks Don, I will certainly check the vent, it would be nice if it were that simple.... Thanks yxmj, I suspected this but good to have it confirmed. Gene

About this...... My 88 4.0 left in 1st or reverse will drift very very slowly even on a slight incline, especially if the engine is hot. It's not the clutch slipping, it will roll an inch, stop, then roll another inch, and so forth. I have not checked compression recently. Ironically, I just broke a rear parking brake cable this past weekend, so with no parking brake I have been reminded of the "drift" New PB cable just came today from Rock. Ordered it Sunday. Gene

Hi everyone, 88 Comanche 4.0, Dana 35 rear axle. Looks like the left rear seal is leaking, lubricant starting to run onto the brake backing plate. Any way to change this without a hydraulic press? Any tips or write ups? Thanks Gene

Hi Bryce, Electric theory was something that always puzzled me. It's just one of those things where you struggle with it, and try to understand it, and then all of a sudden something clicks and it all makes perfect sense. First, a 12 V system is not really 12 V. If you put a voltmeter on a battery, fully charged, the voltage will be approximately 12.8 V. When the vehicle is running, the alternator will boost voltage up to about 13.5. Load up the electrical system, headlights and blower motor, and voltage will fall below the 13.5. When cranking the engine, voltage may be below 10. Second, and this point has been well made many times, don't forget the ground half of the circuit. One half of the circuit is from the battery out to the electrical load. This may include fuses, switches, relays, and one or more splices. Any of these can develop corrosion, the corrosion will put resistance at that point, that resistance will drop the voltage available downstream from this, and generate heat at that point. Once electricity has flowed through the load, it then has to get back to the battery. In your home wiring systems, their are two wires, so the return is simple. Automotively, electricity flows through a short wire to a piece of metal on the vehicle frame, then travels back through the vehicle frame to the negative post on the battery. So think about that part of the circuit. Maybe the ground wire, where it's fastened to metal of the body or frame, has developed corrosion. Maybe, as electricity travels back to the frame, there's corrosion at the negative battery terminal. And, especially problematic on the Renix, the body ground return has to go through a small ground wire to get back to the engine block, to get back to the battery ground terminal, to get back to the battery. This is why Cruiser, among others, makes such a big deal about making sure the ground half of the circuit is addressed. Hope this helps. Gene

"A little basic math, lets say a 35W bulb is pulling 3 amps. at 11.8V it would be at 35.4W. Take that same bulb and lets leave the amp draw at 3, at 13.8V it would be pushing 41.4W. Feel free to nit pick my math or example here as I am sure it has a flaw or two. I just wanted to emphasize that the bulbs seeing nearly 14 volts will make a difference." So...at the risk of being a nitpicker.... Amps=volts/resistance I=V/R Resistance stays the same. If voltage changes, then current changes. Let's round your numbers, make the bulb 36 watts, and the voltages 12 and 14. At 12 volts, 3 amps flowing makes 36 watts. So the resistance (ohms) is 12/3 or 4 ohms. Now increase the voltage to 14. The ohms stay the same at 4. So now the current is 14/4 or 3.5 amps And the new watts are 14 X 3.5 = 49 watts When I'm not sure about is whether the wattage is calculated at 12 V, or at a higher voltage. Since automotive electric systems actually run at about 13.5 V, I suspect (just a guess) that the wattage of 12 volt bulbs is actually calculated at 13.5 V. But I don't know that. Hope this helps, and is not just totally confusing. Gene

Hi everyone, I think there is some truth to the shorter bulb life. With the harness, the bulb will have its normal length of life. When a bulb is run at lower voltage, it will last longer than its rated life. For example, house current is 120 V. Back in the days of incandescent bulbs, a "long life" bulb was actually a 130 V bulb. This would give longer life, but less light output. I'm still going to go with the harness. Gene

Similar discussion here http://comancheclub.com/topic/49320-relay-on-blower-motor/ Gene

You did double flare the tubing, right? Gene

Hi Blaine, It's been a while since I've bled mine, but what you wrote sounds right. I remember, generally, lots and lots of time and frustration involved. And lots of brake fluid! Good luck Gene

Hi Scott, Thanks for the comment. About 10 years ago I changed the gas tank, no problem dealing with the lock ring with the tank out. Last year I changed the fuel pump...Didn't remove the tank....I don't think I got the the lock ring very tight...so I have not filled the tank over 3/4 full. Much much easier with the tank out of the vehicle. But I had a full tank of gas when I changed the fuel pump... Thanks Gene

Hi Steven, When everything is dead, do the headlights work? If they do not, the problem is before the ignition switch. If they do, then the problem is after the ignition switch. I suspect that will be the case. Also, when it goes dead, what do you do then? Does it immediately come back to life, do you have to wait for a while, or do you do something to help? Let us know! Gene

Hi Eagle, I have ordered from Rock Auto extensively for probably the last eight years. We have three kids, and six older vehicles in the family. Over all, my experiences have been very good. I can only recall about three times when the wrong part was sent. Once it was the fuel injector "spider" for our 03 S 10. I ordered under the correct number, they sent what was listed as the correct part, but it was not. I called Rock, while I was on the phone the Rock Auto person contacted the manufacturer, found out that Rock was given the wrong number from the manufacturer. They shipped out the right one immediately, and paid return shipping on the wrong item. Second time, minor part, I think there was an online form to indicate that the part was wrong, they immediately shipped a new one. Third, I was redoing the brakes completely on my Comanche (calipers, wheel cylinders, master cylinder, brake lines, etc.). I ordered just about everything from Rock. One of the brake hoses was wrong. I didn't mess with it but bought one locally at Advance Auto. Over all, their parts have been good, shipping has been quick, and I've saved a bundle over the years. Gene

Great writeup, thanks! Over the years I've broken several parking brake release cables. They seem to fray at the far end, it doesn't look like there are any sharp edges, I think just repeated use causes them to fail. I've started pressing down on the pedal before pulling the release. When I don't do this, there is quite a bit more force required to release the parking brake. When I press down on the pedal, the release pulls very very easily. I'm guessing it'll be hard to get replacements for the release cable, so I'm hoping this one will last a while! Gene

Hi Legion, Two things happen: 1. Batteries slowly discharge, even with no external drain. This will be less of a concern in cold weather, more in hot. 2. There is always a little drain into the vehicles electrical system. The clock will be a minor drain, the original radio in my 88 had a bit more drain as well. It doesn't have to be much to drain a battery over weeks of sitting. So: 1. Disconnect the ground cable if the vehicle will be sitting (I use a week or longer as "sitting") 2. Charge the battery about once a month, even if disconnected. Discharged batteries will age (sulfation) faster than charged batteries. Gene

Hi Minuit, Could this be a failing steering damper? The steering dampers have been criticized in a number of posts regarding the death wobble. They will not prevent this. However, they probably would help in your situation. It sounds like you're actually describing a situation where you're noticing the "road feedback" more than you're accustomed. Anyone else have thoughts on this? Gene

Good work Dan! Gene