TR2/3/3A TR3 Red dashlight on...where to start?

[karls59tr]

I installed the rebuilt Advanced Dist and connected the Pertonix as specified....fired up the engine with fresh gas after a 2 year hiatus. I also changed out the large spade connector to the generator. The engine is running smooth an strong...except the darn red light is on. Anyone have any ideas as to what the problem might be. Oil pressure is good. I ran it for a couple minutes but it stayed on. Should go out after start up.

 

[TR4nut]

If its been idle that long, chances are you need to flash the generator field - otherwise it won't have any output. Sorry, can't tell you from memory what the procedure is but it is a very easy thing to do.

Randy

 

[TR3driver]

Indicates the generator and/or regulator are not working. I'd try first revving it up a bit, say 3000 rpm for a few seconds. If that doesn't work, double-check the wiring from control box to generator. Heavy wire (yellow originally) from 'D' to the larger terminal on the generator. Smaller wire (yellow/green) from 'F' to the smaller terminal. Repolarize the generator.

If still no joy, then you'll need to start doing some trouble-shooting. My first step would be to disconnect the two generator wires from the control box, and temporarily join them together with a voltmeter to ground. Start the engine and watch the voltmeter; it should reach 12v with the engine at just a fast idle (no more than 1000 rpm or so). If not, the problem is the generator or wires. If so, most likely the problem is the control box.

There are more detailed tests at
https://www.1978mgmidget.com/Lucas_Generator_and_Control_Box_Tests.pdf

 

[Andrew Mace]

"...I also changed out the large spade connector to the generator" is the very first place I'd check, just in case the connector is somehow bad or it's not getting good contact with the wire. Then, as above....

 

[karls59tr]

Thanks for the input guys. I remember now there was something about touching a wire to the generator terminal to set the the polarity....or what TR4nut said"flashing the field". I'm pretty sure its in the manual and I'll check it out.

 

[Twosheds]

...or what TR4nut said"flashing the field".

I think TR4nut is from aviation like me 'cuz that's what I call it too.

 

[karls59tr]

Well I Flashed the Field with a piece of wire from the small spade on the "dynamo" to the Live Neg Batt post...held it there for 5 secs ...hooked it back up,revved the engine to 3 grand and the red light went out. Say you wouldnt happen to know what the idle speed should be on the TR3 when it has a mild street cam would you?

 

[martx-5]

Mine idles pretty good at about 900-1000 rpm with a 282 deg cam. Glad you got the dynamo working!

 

[karls59tr]

Thanks for the info. Dosn't the 3 look much better without the front bumper...mine's off too.

 

[martx-5]

That was a decision I made very early in the restoration...no front bumper. Every picture I saw of a TR3 <span style="font-weight: bold">without</span> the front bumper looked better to me then ones with it installed. To my eyes, the front bumper gives the TR3 a frumpy look. Besides, I'm really not into concours correct. Nothing wrong with that, but I'll leave that for those that are.

 

[TR4nut]

I think TR4nut is from aviation like me 'cuz that's what I call it too.

Close John, but not quite - the only flying I do is by the seat of my pants! Just remembered that term from some tech info I had stashed away - I liked the sound of it so it stuck with me, just wish I could remember exactly how to do it when asked!

Randy

 

[TR3driver]

just wish I could remember exactly how to do it when asked!

There's a whole raft of valid methods; basically anything that applies 12v of the proper polarity to the field winding. One easy method on a TR is to remove the field wire from the F terminal, and touch it to the A (or A1) terminal. This is somewhat kinder and produces fewer sparks than the method I usually use, which is to jam my pocketknife in between the F and A terminals for just a second.