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TR5/TR250 Its alive!

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Marvin Gruber

Marvin Gruber

Yoda
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Finally, cranked and running. Couple of small issues, little more carb adjustment but fired up and ran for about 10 mintues. One electrical issue that bothers me. I checked voltage at + side of coil with switch off. Had 12 volts. Unplugged the alternator control wiring and voltage went away. Cranked engine up again with wiring hooked up to see if engine would continue to run. Turned sw off, engine died as it should. Am I just reading some phantom voltage at coil from Alternator control?

Marv image.jpg
 
Marvin, are you getting voltage on both sides of the coil?

Wayne
 
Marvin, I should have said how good it looks. A few minor yips is to be expected.
I'm thinking the alternator 12v feed my be crossed or a diode gone bad.

Wayne
 
I'm with Wayne. Sounds like the alternator wiring is supplying current back into the dash warning lamp, and you happened to check the voltage at the coil with the points open. With no current going through the points (or anywhere else), the bulb passes enough for your voltmeter to show 12v. But it won't pass enough to keep the engine running.

Does the dash light glow with the key off and something else turned on (like the heater fan or the points closed) ?
 
Woohoo! Congrats on the build and I really like that blue...far cry from the last time I saw it! My Bugeye should be headed out for paint within the next month or so and I'll be dropping the engine and OD in the MGB in the next week then I can start working on the 4a.
Rut
 
I know on mine the Diode was bad on the original alternator, a local electrical shop re-soldered it and it has been fine since.
 
Hey Marv
It looks like we are at the same place. Even thou this is the second rebuild on the motor in less than one year. All I have left is to install the new steering rack. And reinstall the tunnel and interior.should be back on the road by Sunday .
image.jpg
 
Haven't gotten back to the electrical problem yet. Going to have the alternator checked first. I just cleaned it up and stuck it on. Tach and speedo not installed yet. Wired up overdrive yesterday and got clutch bled. Spring clean up and grass cutting is going slow the finish date.

Marv
 
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