Rebuilt solid state regulator and now ammeter is pegging at +30??

[ianc]

If you are still on positive earth and have a coil marked +/-, then you need to ensure that your wiring at the coil is the right way about. I've pasted some advice here:

Coils for both Positive and Negative earth vehicles were produced, but who knows if anyone has changed a coil for the wrong type in the history of older vehicles, so it is wise to check polarity of the spark (see below for testing polarity using a lead pencil).

With early coils, swapping the CB and SW leads will switch polarity of the spark. Later coils use + and - but the requirements are the same.

To test the spark direction with a lead pencil, interpose the writing tip of a lead pencil between the spark plug top stud and the HT lead, leaving a small gap either side of the pencil tip. If the polarity is correct, a flare between the pencil and the spark plug will be seen (if the flare is between the pencil tip and the HT lead, then the polarity is reversed).

 

If the coil is incorrectly connected, the car will not perform well.

 

Ian Cornish

[F1loco]

Making progress. Re-wired the regulator per the wiring diagram. Now, it tops at just under 20amps. But still rises quite a bit on revs. That being said, the battery was only 12.4v at rest, so I am charging it once again. Figure the "mis-wiring" by the previous owner may be the cause of the battery drain.

 

In doing this, I notice something strange with the starter solenoid and starter. I am guessing someone installed a negative earth starter, if I had to guess:

 

 

The black negative from the battery going to the left post, as you look at in the car installed on the front firewall. To that, the two brown wires from ignition and regulator go to the same post, as well as the black wire to the starter. The white/red wire from the ignition switch then bypasses the solenoid all together (ie, the bottom post) and is screwed into a mounting point just below the black wire on the side of the starter. The post on the right has nothing connected to it. Has anyone seen this? Tried installing it correctly but no movement at the starter, so I am assuming the red/white to the starter is an attempt to make a negative earth starter work? Is this, or could this, cause any further problems?

[angelfj]

Regulator was through a guy here in the states that is well known for building the boards for converting the coil set up.

 

He inquired as what "dynamo" I had and to be honest, there was not a single case stamping I could find on it for him. We anticipated it was a replacement type with this figures:

 

 

The original Lucas dynamo fitted was model C40-1, part number 22700.

Details from the Workshop Manual are as follows :

Model : C40 - 1

Type : Two brush, two pole, compensated voltage control

Rotation : Clockwise

Field resistance : 6 ohms approximately

Maximum output at 13.5 volts : 22 amperes at 2050 - 2250 r.p.m. (connected to a load of 0.61 ohms).

Brush tension : 22 - 25 ozs. (0.62 - 0.71 Kgs).

Minimum brush length : 11/32" (9mm)

 

 

Did you have similar problems not knowing your dynamo wasn't the Lucas specs? I just tried to take a reading at the regulator from the brown/yellow and brown/blue coming off the dynamo and was getting MV readings, not even a V? But when I rev'd it, the battery readings would go from 12.7 to 14.2?

F1loco, I'd love to be able to assist you, but not sure that car you have. Your icon is a TR4 or 4A, I think. The TR4 utilized a C40, with maximum rating of 22 amps. So, the current limit should not be set above 22 amps.

 

Still not sure who supplied your regulator. Mine came from Bob Jeffers of Wilton Auto Electric, Wilton, New Hampshire.

Does your solid state regulator look like this (the unit on the right)? http://i135.photobucket.com/albums/q159/angelfj/My_installation_1_DSC07015.jpg

 

What do you mean by, " boards for converting the coil set up" Do you mean ignition coils? I don't believe Wilton do anything with ignitions.

 

I have/had an original LUCAS C39PV2, with large letters stamped on the case, fairly easy to read. The aftermarket LUCAS-type units have no markings on the case.

 

Another very important question, which LUCAS control box did the solid state regulator replace? The TR4 would have had the LUCAS RB106-2 fitted. Is this what you had?

 

There are two terminals on your dynamo. The larger terminal is the armature circuit and is connected by a Yellow/Green wire to terminal 'D' on the regulator. The smaller dynamo terminal is the field, connected by a Yellow wire to terminal 'F' on the control box. There should be NO appreciable voltage between these two terminals.

[angelfj]

Making progress. Re-wired the regulator per the wiring diagram. Now, it tops at just under 20amps. But still rises quite a bit on revs. That being said, the battery was only 12.4v at rest, so I am charging it once again.

 

 

This is good news and indicates that the regulator is limiting charging current to approximately 20 amps. Your making progress.

[F1loco]

Yes, got mine from Wilton Auto. Problem is no ID'y marks on the dynamo, so best guess is aftermarket. Will let you know results tomorrow after a full charge on the battery tonight.

 

Found a site with the aftermarket starter in the car. Apparently common practice to bypass the solenoid and run the red/white wire from the ignition to the starter, along with the negative/black wire.

 

I'll eventually get it straight. Cooling system is next on deck...

[F1loco]

"There are two terminals on your dynamo. The larger terminal is the armature circuit and is connected by a Yellow/Green wire to terminal 'D' on the regulator. The smaller dynamo terminal is the field, connected by a Yellow wire to terminal 'F' on the control box. There should be NO appreciable voltage between these two terminals. "

 

Odd, my Brown/yellow is actually the heavier of the gauge than the Brown/green(bluish) wire....

[F1loco]

Well great news...after wiring the regulator correctly and a good charge on the battery over night, it appears to be working correctly, maxing out at just under 20amps, and running 5-10+ most of the time. Now on to the cooling system this weekend...Thanks for the help and feedback.