New metal halide fixture acting up

[Katfsh]

I bought a metal halide fixture off of ebay and its not working right, I contacted the seller about but thought that i would get the opions of every one here. At first it would not cut on so I took it apart played with the bulb and got it to barely cut on, dimmer than an led, so I took the bulb out and flipped it around and bingo worked great. I cut it off after it ran for about seven hours and let it sit for about 2 hours and cut it back on and its only dim again. i checked out the voltage earlier today and it seems as if every thing is right, 120v going to ballast and 980 coming out of the ballast just as it list on the side of the ballast. Would the bulb be causing this? Any one have any suggestions before I contact this guy again?
thanks
katfsh

 

[Len]

What type of ballast is it? is there a coil and "canned" capacitor in the enclosure? Look for an ANSI code (for metal halide ballast, this number will start with a M, something like M59 and may be three digit). We should first determine it's the proper ballast. Sometimes ebay sellers don't know what it is they are really selling.

 

[Katfsh]

well len I looked and there is no anse code on the outside of the ballast box, and I really dont want to crack this thing open until i talk to this guy some more. This is a total fixture with one 250w wh 15000k bulb and two actnic power compacts with four leds, and the mh ballast is external. I played with it some more this morning when I cut it one it barely glows on just one end of the bulb and can take the bulb out and flip it around and it still glow on the same end of the bulb itself. Whats really odd to me is that I can stick the end that glows to one side of the contacts and leave the other end not touching anything and it will still glow. If I put the bulb in and while its glowing I can thump it or tap it, it will light up as I touch it but then it goes right back to the dim. Its not the cantacts bc they are very tight.

katfsh