Glow plug/ignition problem

[Dieselnoob]

Hey everyone,
I'm new to this forum/diesel world... So about a year ago I made the jump to buy a diesel. Since I only know basic stuff about them I went cheap did some research and bought a 86 6.9L f250 4x4 4spd. It's ruff looking but the frame, engine, and drivetrain were solid. Now to the problem being winter in md I was having glow plug problems so I replaced them it ran fin for a few days I even got a 7degree start no plug in.Now though my trucks glow plugs won't switch on only sometimes if I jiggle to key off/on so I replaced the glow plug relay still nothing. So u plugged her up now when she's running (even after about 15miles)she will idle and move fine but when I take her out of gear coming to a stop she dies but will start right back up. But!! If she fires up on the glow plugs she won't die when I take her out of gear... So I traced to problem to the positive wire running to the ignition (meter test)only sometime will it get power from the ignition. Now should I bypass the key ignition with a switch or replace it all? And could all this affect my idle? Maybe the fact that it works when it wants to and the sudden voltage change make her die? I know my gas engines but diesel

 

[Dieselnoob]

PS- I need her running good I have a 14k tow I have to do this week(truck is included in that)

 

[79jasper]

Try replacing the ignition itself.
Or just bypass with a switch.

Sent from my USCC-C6721 using Tapatalk

 

[Wyreth]

Sounds like you may have a stuck metering valve in the IP. Or worse a dying IP.

Pour a couple quarts of ATF in the tank, and do the "atf in the filter trick." That's where you take off the fuel filter, dump the diesel that's in it into a catch can, then fill it with ATF. (or dieselkleen, your choice) Be sure to only fill the filter from the ring of small holes around the outside. That way it filters all the ATF. Even particles less than one micron can damage the IP. Once full, put it back on, then start the truck. In about 30 seconds or so, it will sort of mellow out and get quiet. That's when you know it has started burning the ATF from the filter. Immediately shut it down, and let it sit overnight. Next morning, start it and let it warm up. Then drive it around and kick the crap out of it. Don't be afraid to repeat it if necessary.

Hopefully that will solve the dying issue. If not, you may be looking at replacing the IP. If so, talk to Conestoga diesel. DO NOT cheap out on an IP you will be very sorry. (also please read through the hall of shame before you buy anything for your truck)

 

[Dieselnoob]

Thanks I ended up bypassing the the ignition gp to a push button. I kicked up the idle a bit and she runs fine now but I will run some ATF through her this weekend after I do this tow tomorrow am.

 

[Desert Diesel Dog]

have you looked directly at the ignition switch?

my engine wouldn't keep running. if you started it, but didn't hold the key 'thingy' over... it would just let the engine die.

i had to replace a switch because it was actually coming apart at the 'seem'. what I mean is that it had opened up about an eighth inch on one end [still KINDA worked] i don't know how it happened, but the two 'arms' that were holding it together were bent out of position... allowing the plastic part to separate from the metal part.

i have heard of another case of the switch coming apart.

after i replaced the switch with a new one, i bent in the two arms of the old switch [with a vice] leaving me with a spare that might still be good. [who knows?]

i was able to replace the switch Without dropping the steering column. as i remember, i disconnected then re-connected the connector while the switch was unbolted and out of position.

anyway... after replacing the switch it started and ran perfectly.