jdemaris 6.9 glow plug question

The brand of the plug won't make a bit of difference in actual starting - except - dual-coil self-regulating plugs are basically burn-out proof, while many other's are not.

I agree with Bob that there isn't any better out there than the dual-coil Beru plugs. That being said, the single-coil Berus will burn up just as fast as an Autolite, Champion, Delco, etc. Bosch, Wellman, Delphi, etc. all sell dual-coil plugs now that hold up just as well as the Berus. If you buy new plugs today from Ford or GM - you get Beru dual-coil plugs. It may cost a few bucks more that way - but sometimes it's easier going to Ford if you need them in a hurry.

As I said before - if you want to be sure - you need to check with an ammeter - one by one with each glow plug. It's easy to do and takes little time - and saves a lot of guess work.
I already gave you all the test specs.

In regard to what Alan said about the 6.9s being tough starters? Maybe somewhere - but not with any of mine. My 85 6.9 and my 94 7.3 are both excellent cold-weather starters. Same with my Isuzus and my Dodge-Cummins. Only bad starters I've ever had are my GM 6.2 diesels. The best of the lot is awful - and the worst id more awful. My 1985 with the 6.9 can sit for two months - and then I go out and try to start if at zero degrees with no block heat - and after 15 seconds of glow-plugging it starts right up. With my 6.2s? At zero - you can more-or-less forget it unless you've got the block heater plugged in. And at 45 degrees F above? They still need a good 10-14 seconds of glow-plugging. My 85 6.9 currently has Motorcraft ZD1A plugs - Ford # E5TZ12A342B - which came as either Bosch or Beru years back and now are usually only dual-coil Beru.

Motorcraft glow plugs, from the Ford dealer, are Beru, and as good as you can get.

It's time to get a test light, and probe at EACH glow plug, to be SURE they are all being powered up. There are fusible links, and various other things that can go wrong in the harness, preventing power from getting to one or more of the GP's. Just because the"wait to start" lamp is lit, it doesn't actually PROVE the GP's are getting power.

If one or more of the GP's is not getting power, or is "open" the system voltage will rise quicker than it should, signalling the controller to shut off the GP's SOONER.

In other words, the "glow plug on time" will be LONGER with ALL the GP's being properly powered than if there are one or more that are not heating.

Another thing you can do, IF you have access to a DC clamp-on ammeter, or an in-line ammeter is to do as demaris suggested, and check the AMPERAGE actually being drawn by EACH GP.

Check glow plugs of course.

But, that 6.9 Binder is one of the worst engines ever for not starting unless it has the required spin speed.

New batteries, cables and a fresh starter will just simply make a new engine out of it as far as cold starts go.

Allan