Hello all,
I purchased a Autometer Z-Series 2890 Tachometer. I installed it on a 1985 Toyota Land Cruiser FJ70, with a "carbureted" 3F engine. The ignition system at some point was upgraded to electronic. The Ignition module is a small, thin height, square grey 2x2 inch unit, that mounts to the canister coil with a push on spring like clamp / mount. I have tried to acquire info on this module, but other than the bottom showing it's made in Canada, there is nothing online about it. It looks like the old style Land Cruiser, or Ford ignition modules from mid 80's and older.
I also installed a MSD Blaster High Vibration coil. MSD claims if used with stock points, or stock electronic ignition, that a ballast resistor should be used. I have the MSD .08 ohm resistor and have been using it since installing everything, making the coil have 1.5 ohm resistance total. I contacted MSD and asked if I should use a 3 ohm resistance coil since I am running a 6 cyl engine, they said no, it would be fine. (I asked due to Pertronix and HotSpark saying to use 3ohm for a 6 cyl with their units)
The Autometer 2890 tachometer worked perfectly for about 5 months, then started having problems. It would be fine for a while when first starting the engine, then after a few minutes, would start falling to 0 at idle. As soon as the engine revved, the tach would jump up and show accurate rpm. This occurred for several months until finally, the tach always sits a 0 at idle, and is about 1000 rpm lower than what it should be when revving the engine. Again, it was fine for many months before this started occurring.
So I just ordered another Autometer tach, but before I install, I wanted to verify or expand my knowledge on some things. The electronic ignition module does NOT have a tach signal wire. So I ran the tach feed wire to the Negative side of the MSD Blaster Vibration coil. Is this acceptable? At what point is it not safe to do so? I ask, because in the instructions it says not to hook up the tach feed wire to the coil on a CDI ignition system. If one did hook it up to the coil on a CDI system, what would be the symptoms? Immediate failure? The symptoms that happened to my tachometer, would those be similar if one hooked up the tach to a CDI system, or is the failure that occurs in that instance total failure?
"Warranty will be void if connected to coil when using an aftermarket ignition box such as, but not limited to products from the following manufacturers: MSD, Crane, Jacobs, Mallory, Holley, Etc.. Prior to installation of your tachometer, check with the ignition box manufacturer for recommended tachometer signal location."
Any help here would be great, I don't want to lost another tach if I am missing something. I'm assuming that the CDI systems are the bigger ignition boxes, but I guess the one sitting on top of my coil could be.. Maybe?
I purchased a Autometer Z-Series 2890 Tachometer. I installed it on a 1985 Toyota Land Cruiser FJ70, with a "carbureted" 3F engine. The ignition system at some point was upgraded to electronic. The Ignition module is a small, thin height, square grey 2x2 inch unit, that mounts to the canister coil with a push on spring like clamp / mount. I have tried to acquire info on this module, but other than the bottom showing it's made in Canada, there is nothing online about it. It looks like the old style Land Cruiser, or Ford ignition modules from mid 80's and older.
I also installed a MSD Blaster High Vibration coil. MSD claims if used with stock points, or stock electronic ignition, that a ballast resistor should be used. I have the MSD .08 ohm resistor and have been using it since installing everything, making the coil have 1.5 ohm resistance total. I contacted MSD and asked if I should use a 3 ohm resistance coil since I am running a 6 cyl engine, they said no, it would be fine. (I asked due to Pertronix and HotSpark saying to use 3ohm for a 6 cyl with their units)
The Autometer 2890 tachometer worked perfectly for about 5 months, then started having problems. It would be fine for a while when first starting the engine, then after a few minutes, would start falling to 0 at idle. As soon as the engine revved, the tach would jump up and show accurate rpm. This occurred for several months until finally, the tach always sits a 0 at idle, and is about 1000 rpm lower than what it should be when revving the engine. Again, it was fine for many months before this started occurring.
So I just ordered another Autometer tach, but before I install, I wanted to verify or expand my knowledge on some things. The electronic ignition module does NOT have a tach signal wire. So I ran the tach feed wire to the Negative side of the MSD Blaster Vibration coil. Is this acceptable? At what point is it not safe to do so? I ask, because in the instructions it says not to hook up the tach feed wire to the coil on a CDI ignition system. If one did hook it up to the coil on a CDI system, what would be the symptoms? Immediate failure? The symptoms that happened to my tachometer, would those be similar if one hooked up the tach to a CDI system, or is the failure that occurs in that instance total failure?
"Warranty will be void if connected to coil when using an aftermarket ignition box such as, but not limited to products from the following manufacturers: MSD, Crane, Jacobs, Mallory, Holley, Etc.. Prior to installation of your tachometer, check with the ignition box manufacturer for recommended tachometer signal location."
Any help here would be great, I don't want to lost another tach if I am missing something. I'm assuming that the CDI systems are the bigger ignition boxes, but I guess the one sitting on top of my coil could be.. Maybe?
