Yea definitely cycle them plugs longer than that. In that cold you could do 14 seconds easy. You did half of that. I'd much rather do one single long cycle than having to do several cycles. When you do several cycles like that it's hard to calculate just exactly how hard you're being on the plugs. But I guess you have to keep in mind that you need the good glow plugs to cycle them that long. If you have autolites or something other than Beru's you'll fry them cycling them longer than 10 seconds. Hell I had one new autolite I found on the shelf in the garage that I ran a test on and it only went 6 seconds before it fried.
I have beru's on the front half, gonna do the back half on saturday, I guess I could of cycled them twice or maybe a lil longer, The PO, so far, had two different kinds in there. The last two I pulled were AC 8G 10.5v (not swollen) and two were junk autolites both swollen
. even though the ACs aren't swelled up I still want to have the ZD1s all around cause everybody swears by them.after I do the other four I'll do another cold start video if it get's that cold again. Thanks for the advice