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Moss Lucas Control Box/voltage regulator

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TulsaFred

TulsaFred

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I bought the expensive pre cleaned and pre adjusted Lucas control box for my bugeye. There is a write up on their site describing how and why they offer these at twice the price of the regular units. They specifically state that they adjust the regulator to limit voltage to 13-14 volts and that they know this is not the recommended setting as original (lucas control box tests state 15-16 volts).

Well, i did register charge when i installed the new unit (previously wasn't charging at all). However, I took for a drive last night (headlights on) and the battery drained and would not start the car. Got back home after pushing the car and popping the clutch to start.

I tested the generator and it puts out increasing voltage with increasing speed, registering 7.85 volts at idle but quickly up to 18 volts at about 2000 rpm or so. I stopped there, but surely would have kept going higher with rpm.

I hooked all back up and tested charging voltage at the battery with regulator in place. Shows 13.5 volts (in line with the 13-14 volts Moss specifies).

SO... what gives. It seems to me that limiting the voltage to 13.5 is insufficient to handle the load of the headlights, other lights, etc.

Thoughts ?
 
Hi Fred,
How old is your battery? you might need to take it to a battery shop and have it thoroughly tested. It might have a dead cell or two. 13.5 V from your charging system should be fine. that service MOSS provides in adjusting those voltage regulators is WELL WORTH THE MONEY btw :smile:!
 
I have a whole pile of RB 106 regulators that are probably good but would like someone to go through them and clean and adjust them. Be nice to know who could do that. I'll bet the old ones are more reliable than the new. I tried to adjust one that a PO had been fooling with and burned up a generator with. I fared no better and cooked a generator as well so now I'm a little gun shy.

Kurt.
 
There used to be a guy who would convert your mechanical regulator to electronic....and it looked just like a std. control unit from the outside......was wilton electric. this is what 60 Frog has in it. Unfortunately the owner has passed in 2013. When I had my first BE, I went through numerous control boxes and generators! Anyone else ready to take up the slack!
Scott in CA
 
I called Moss technical support and spoke with Blaine (I prefer Moss for most parts due to the availability of tech support on 50 year old cars!).
He didn't think the control box was the problem and wants me to check the voltage while driving with headlights on, and also to check voltage while cranking, then report back. I'll check these things. Excellent resource.
However, I'm still thinking that setting the voltage at 13.5 may be the issue. Since current is directly related to voltage, the batter charge current at 13.5 volts is low relative to the charge current at 15+ volts as per the factory setting. The lower charge current may not be able to keep up with the drain from the headlights and fuel pump?Seems to charge fine as long as load is minimal.
 
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