1994 6.5td Glow plug voltage.

[bradthefixer]

Hello All, What voltage should I read at an individual glow plug? with key on engine off, no other loads. I just replaced the original GPs at 273,000 miles. Been checking them every 2 years so they came out easy. except No 8 got it loose then hit the key and pow! its out. I used a 2 1/2'' hole saw for a hole in the fender well, then patch it with an electrical mastic pad. All the old plugs read less than 1 ohm, bench test with good Batt all were good. Decided to change them before they get fat and wouldn't be able to get them out. Also was starting hard it seemed. New Bosch Durotherm's, and it's still starting hard. Checked all new plugs with ohm meter before I installed them. So what voltage should be sent to the plugs if the GP rely is good? I put a lot of miles on this truck without any cheesy mods. Best vehicle I've ever owned. 100% stock except a Rhino muffler. I've gotten a lot of good info from this site. Glad I finally figured out how to post!

 

[ak diesel driver]

hard start the first thing I would do is put a clear line on the IP return line

 

[Will L.]

Voltage should be identical to voltage at GP relay post. Near voltage of battery, maybe 0.1 volts less.

 

[bradthefixer]

Have clear fuel tube at IP, no air bubbles

 

[NVW]

I've never checked mine with a DVM, but the dash gauge drops significantly.