Question on glow controller function

[Terry Donlin]

I've swapped a '81 6.2 "J" into a '91 suburban 1500 body. I've bled the injectors and it still doesn't want to start. I was measuring the voltage on one of the glow plugs and most of the time it would only show a fraction of a volt after turning the key on with flicker around 12 volts about every 7 seconds. Is that voltage normal output from the controller? I expected it to operate at 12 volts for a few seconds to get the glow plugs hot.
Advice?
Thanks, Terry

[NH2112]

Well I'm normally not one to recommend throwing parts at a machine till you fix it, but this time I have to recommend just putting an 85-93 glow controller in and enjoying the closest thing to trouble-free starts that exists. The swap is pretty simple, with the schematics in the DP troubleshooting guide telling all you need to know.

[Terry Donlin]

Phil,

I have the newer style controller installed out of the '91.

I enlisted my wifes help *turning the key" and was able to watch the glow plug voltage. It came on for about 3-4 seconds then only flickered around 11 volts every few seconds.

Are glow plug wires sensitive to which glow plug they are attached to? I'm not sure.

Terry