TC18 Alternator Light is ON

[guyw]

Well, it looks like my TC18 is having the same issue now. The battery is a couple of years old, but tests OK with a battery tester and under load. It charges fine using an external charger. The Alternator puts out well over the minimum 28 volts AC under no load and at high throttle as specified in the repair manual. The battery tester shows just the normal battery voltage while the engine is running. I have checked and cleaned all the connections to the battery, alternator and voltage regulator. The charge light will sometimes go out when the engine is running over 2000 rpm, and is usually on when at idle, but sometimes it will go out even then, but the battery tester shows just normal battery voltage no matter what the engine rpms are or the state of the charge light. I am assuming I have narrowed the problem down to the voltage regulator, but since the dealer is closed for the long weekend and won't be open until Tuesday, thought I would post to see if anyone had any thoughts. Thanks!

Guy.

 

[Gedfish]

I'd second the reg as your most likely source of bother if the alt is outputting OK. The reg would be obvious if it's external (I like the external types because it makes servicing and fault detection easier). Good luck. If you're having no success, don't be too proud to call the autoelectrician!

 

[jinman]

Of course, I don't have a TC18 electrical schematic, but if I were having a problem with the alternator and found out New Holland wants $233 for the alternator and $150 for the regulator, I'd be checking out this 40 amp alternator with an internal regulator for about $70 or one of the one-wire Delco models.

 

[guyw]

Jim,

As usual, great advice. I found a source for the voltage regulator via eBay for $70. Am going to try that first. If that doesn't work, I will try the 40 amp alternator. I have the wiring diagrams for the TC18, TC21 and TC21D. The 40 amp alternator is for the TC21D and would probably just bolt right in, but it would require some re-wiring and possibly the addition of a 3.4W light bulb to substitute for the "electrothermal choke" shown in the wiring diagrams.

Guy

 

[guyw]

Received the new voltage regulator I bought on eBay. It is slightly smaller in size, and the connector latch is male rather than female on the original. I replaced it this morning and tie wrapped the connectors together. Fired it up and no charge light anymore and the battery tester shows the circuit is charging again, so I should be all set. As the voltage regulator I got was only $70, I have hopefully saved $80 over the part from New Holland.

Guy.

 

[jinman]

Wow! You did a nice job and saved a bundle.:thumbsup:

 

[rbsharp]

Guy ,

how is that regulator working out you got off ebay ,I have a TC21 that has a bad one on it because to starter key keep sticking and let the glow plugs keep running,the picture of your old regulator is the same as my and the dealer says all electronic part on TC18 -TC24 are the same

 

[rodster]

I just bought the same voltage regulator on Ebay, performed the same install as guyw. Worked like a charm. Thanks guyw and tractorbynet

 

[guyw]

Sorry I missed this post. Was in CA for three weeks about this time and just marked everything as read when I got back rather than trying to read through all the posts. I have not had any problems with my charging system since I replaced the regulator.

 

[guyw]

I just bought the same voltage regulator on Ebay, performed the same install as guyw. Worked like a charm. Thanks guyw and tractorbynet

Great! Really glad it worked out for you too. As I just posted, I have not had any charging problems since I did my install.