I have a 1983 project Bombi I bought a couple of years ago that I’m putting the finishing touches on. I’m currently trying to solve a charging system issue and could use an assist.
The machine has the 60 amp alternator option which uses a Standard Motor Products external voltage regulator with the original Ford industrial 1.6 liter engine. The specific issue I’m having is with the alternator light on the dash.
The original alternator dash light was trashed so I replaced it with a 12 volt LED indicator light. The LED light comes on when I turn the key as it should, but it stays on when the engine has been started and is running. The alternator light is supposed to turn off once the engine starts. The voltage regulator seems to be doing its job. At the battery I’m measuring about 14.5 volts with the engine running. Maybe that voltage is too high?
Thinking that the voltage regulator was doing its job and an old school incandescent lamp might be what was needed, I removed the LED light and replaced it with a 12 volt incandescent lamp. The weird thing is the old school incandescent lamp does not come on at all with just the key. It also doesn’t come on when the engine is running either. The alternator’s still happy and charging as it should be with the incandescent that doesn’t light up. Without the LED or incandescent lamp the alternator doesn’t work since having a lamp is needed to close the “I” circuit of the voltage regulator in the charging system.
To trouble shoot I checked the incandescent lamp to make sure it wasn’t burned out. It comes on just fine when I hook it up to a 9 or 12 volt battery. So now back to the cat. When I turn the ignition key to the “on” position, I measure battery voltage in the bulb socket at 12.5 volts.
So the mystery is why does the LED light come on and the incandescent one not? Why doesn’t the LED light go off when the engine is running? I’ve checked all the wiring and grounds with a multi meter. Everything checks out with the wiring. I’ve also pulled out the alternator and had it checked at two different auto parts shops. The alternator checks out fine. So now I’m down to the voltage regulator.
The guys who checked the alternator don’t have a way to check the external voltage regulator and there are no part numbers to be found anywhere on it. The only markings on it are the brand “Standard Motor Products”. Does anyone have a part number for the Bombi Standard Motor Products voltage regulator that’s used with a 60 amp alternator and Ford 1.6 liter engine? Does anyone have a recommendation on a modern compatible internally regulated alternator and associated schematic that I could replace the existing system with? Is 14.5 volts at the battery too high a voltage to be recharging the battery with?
Thanks for reading and for any suggestions you may have!
The machine has the 60 amp alternator option which uses a Standard Motor Products external voltage regulator with the original Ford industrial 1.6 liter engine. The specific issue I’m having is with the alternator light on the dash.
The original alternator dash light was trashed so I replaced it with a 12 volt LED indicator light. The LED light comes on when I turn the key as it should, but it stays on when the engine has been started and is running. The alternator light is supposed to turn off once the engine starts. The voltage regulator seems to be doing its job. At the battery I’m measuring about 14.5 volts with the engine running. Maybe that voltage is too high?
Thinking that the voltage regulator was doing its job and an old school incandescent lamp might be what was needed, I removed the LED light and replaced it with a 12 volt incandescent lamp. The weird thing is the old school incandescent lamp does not come on at all with just the key. It also doesn’t come on when the engine is running either. The alternator’s still happy and charging as it should be with the incandescent that doesn’t light up. Without the LED or incandescent lamp the alternator doesn’t work since having a lamp is needed to close the “I” circuit of the voltage regulator in the charging system.
To trouble shoot I checked the incandescent lamp to make sure it wasn’t burned out. It comes on just fine when I hook it up to a 9 or 12 volt battery. So now back to the cat. When I turn the ignition key to the “on” position, I measure battery voltage in the bulb socket at 12.5 volts.
So the mystery is why does the LED light come on and the incandescent one not? Why doesn’t the LED light go off when the engine is running? I’ve checked all the wiring and grounds with a multi meter. Everything checks out with the wiring. I’ve also pulled out the alternator and had it checked at two different auto parts shops. The alternator checks out fine. So now I’m down to the voltage regulator.
The guys who checked the alternator don’t have a way to check the external voltage regulator and there are no part numbers to be found anywhere on it. The only markings on it are the brand “Standard Motor Products”. Does anyone have a part number for the Bombi Standard Motor Products voltage regulator that’s used with a 60 amp alternator and Ford 1.6 liter engine? Does anyone have a recommendation on a modern compatible internally regulated alternator and associated schematic that I could replace the existing system with? Is 14.5 volts at the battery too high a voltage to be recharging the battery with?
Thanks for reading and for any suggestions you may have!