75 jd 400 elec start headlight issue?

[Burdvw]

Hey guys,
I have a 1975 jd 400 with electric start and i keep blowing headlight bulbs. i was told by a friend that in some sleds you need to have a battery otherwise you will keep blowing lights because of the altenator putting out to much voltage i dont know how true this is and wanted to ask you guys or do i just have a bad voltage regulator? i also am worried that if this is true by not having a battery am i doing damage to the electrical system? any help would be great!!!

thanks chris

[JD600]

I would install a new Voltage Regulator. Does the light get extremely bright right before it blows out? Also, if you don't have a battery in the sled, i assume that there is a bypass plug installed in the main wiring harness where the electric start harness would plug into it?

DE

[Burdvw]

yes there is a bypass plug installed and yes the bulb gets extremely bright then pops

[JD600]

I would definately say its a voltage regulator issue. You might try cleaning the ground connection on the regulator as a poor connection won't let the regulator function correctly

DE