I have a '89 F350 7.3. I am new to diesels and my truck. The truck is unmodified except for having the fishbowl removed. The problem existed prior. My truck has 66k original miles (know the previous/original owner) and runs very well, but if she sits for more than 8 hours, she is a bear to start.
The mornings here are currently in the low 60's and the evenings have been dipping into the fifties, but even if I crank the truck in the afternoon for the first time I have to go through the startup cycle four or even five times before she finally roars to life.
I do not wish to burn the starter up so I only hold the ignition just a few seconds (maybe 4 tops) upon each attempt. When the truck is hot, it will start just by bumping the ignition switch. When it starts (after being down a while), I get the customary PUFF of bluish smoke, which will not come back until the next extended down time. I am currently running Power Service in each tank at every fillup. She accellerates and idles great - just have to sweet talk her evry morning.

 

Glowplugs?????

 

Have not tested the GP's. The light comes on for ~6 seconds initially and I can hear the eight little clicks for the "firing" of the plugs. Would the GP's die after such short mileage?
If the truck is plugged in, I can start it with no problem. I have read previous threads discussing how to test the GP's and will try this.
Thank you.

 

I replace my glowplugs about once a year. They are not too expensive and pretty easy to do replace. Test them out and I bet that is the culprit.

 

Glow plug system, somewhere. Check the plugs first. Get the Ford/Bierut type. Not them freakin champions.

 

I Would Check The Plugs But Also This May Lead To The Pump,,i Was Having Similar Problems With Mine And Checked The Plugs And They Was All Good,wound Up Being The Injection Pump.when I First Took Mine To The Local Shop They Popped The Hood And Got My Rpms Up To Around 2750 And You Could Hear It Breaking Down A Little So They Knew Right Away What It Was.i Would Give This A Try And See If Yours Breaks Down Any.

 

if ya plug it in and it starts rite up its the glow plugs for sure hands down. either bad plugs or controler. or wiring just have to check it over.

 

Glow plugs or Controller or both, also, you shouldn't hear 8 clicks, the glow plugs don't click, the relay does.

 

Thanks to everyone for the great insight.

 

Dieselsauras,
My 2 cents, install a manual switch for your GP's, works great, here's the link:
http://www.members.shaw.ca/k2pilot/G...%20diagram.jpg
saigon

 

Appreciate that, Saigon.

The schematic is a nice touch.

 

My 87 7.3L has almost the identical problem... I feel like its my GP or controller but I have checked all of my GP and they are all working... one question, though: When the GP are on I'm only getting about 9-9.75 volts to each plug. Does anyone know if this is correct or should I be getting 12 V? Also, I found out that my GP stay on even after my light goes off (for about another 10 seconds before they start cycling). Sorry to kind of post a question under your thread, but I thought some of my info might help... as I said my truck has exactly the same symptoms as yours.

 

[QUOTE=daddydcs]I have checked all of my GP and they are all working... QUOTE]

How did you check them? When they go bad they go "open," to check, you have to REMOVE the wire, and check for continuity with an ohm meter or a test light.

The glow plugs are 6 volt plugs, so they should function with anything more than that, but I'm pretty sure they are supposed to be energized with 12 volts for a faster start.

Most people on FTE who have had GP problems have bypassed the GP controller, and added a pushbutton.

 

Here are several solutuions, the starting problem after it sits for a while could be linked to your injection pump. The gate valve wears and wont seal properly and aollows fuel to drain back into the fuel line causing a slight air gap, the truck starts and then dies immediately right. Its the pump most likely. The injectors when you here the click noise the module is designed to rapind click so the excess fuel that did not burn during start up burns off, its an emission thing. YOu should only here the one click at first and then the on off of the module. Also try this dont watch the glow plug light. turn on the dome light when you get ready to start and watch it dim when it brightens up try to start it. Ford put put a bulletin years ago that the light was not enought time to get hot enough. Try that the let me know. I h ave more tricks. If y ou bypass the module with a switch, yes it will work but they dont last as long. The system works if all the compnent work together.

 

Yea,
I agree with Ambmech, could be your pump............but I don't agree on the bypass switch not lasting long.If you follow the diagram to the letter you wont have any problems starting even in the coldest weather, I ripped off my controller when it started acting up, came on while driving once in a while and and fried the plugs,if you have crappy glow plugs, motocraft and such, the tips will break off and drop down on the pistons, you can imagine what that can do. On the other hand don't get paranoid over your controller, it may last the life of the truck ,but keep a real close watch on it they are known to fail.
Saigon