so i recently bought a 86 f25 6.9L diesel, the glow plugs warm up very slowly, when i turn the key, the light flashes on average about 60-70 times, then its also making a very loud clicking noise from the engine compartment, i think its the relay and im not sure if its suppossed to do that, i have to let the glow plugs "warm" about 7-10 times for the truck to start. i think its the relay, but im trying to spend as little as possible to fix it.

along with that issue the transmition shifts really hard from first to second, and to third, a friend told me its supposed to, i dont believe him.

and the engine temp light is always on, ive checked the coolant levels and they are good, the actual temp gauge says temp is normal...

HELP???

 

The relay must be working since the glowplugs are getting power. That is probably what all the clicking is about. Since it's clicking rapidly, I am going to guess the controller that controls the relay is going south.

I am thinking you have the older controller setup. On my truck I have the newer all in one setup in behind the aircleaner on top of the engine. Check yours out, if you have the older setup your relay is over on the pass side inner fender(along with the starter solenoid) and your controller is somehow screwed into the engine near the firewall.

I have never personally laid eyes on this setup. But I hear over and over that these old controllers can go bad and turn your glowplugs on all the time, and burn them all out. If you can find this thing, see if it's the original one which was prone to problems, or maybe it's been replaced.

They have a few problems with the type I have also, but mainly the type I have is sensitive to wiring connection problems and burnt out glowplugs. The system has to be in tip top shape for it to work correctly. So I converted mine to a manual pushbutton. When I start my truck, I turn the key to run, and then hold a pushbutton in for about 5 seconds, crank it about 3 revs, and then hold it in about 5 seconds more, crank it again, and if it's fairly warm outside, it will crank right up. If it's cold I might have to hold it for another 5 seconds, or if I start out and it's really cold I will sometimes hold it for 7 second or so. Most all heavy equipment is like this with a manual glowplug control of some sort. Some people like this setup, some people don't. You could change your setup to this also if you wanted to, and not bother with the controller.

 

so i have looked all over my truck and the wires to the controller have been cut and spliced, the glow plugs still dont warm up, so i was wondering if anyone had a diagram of how to wire in the push button or can explain it to me very well?

thanks again.

 

What type of controller do you have? Does it look like this? And is mounted at the back of the engine?

glowplugcontroller.jpg Photo by franklin24401 | Photobucket

 

yes its mounted in the rear of the engine behind the air intake, on the driver side. but the controller no longer works since the wiring has been redone to avoid using the controller, but the glow plugs just wont warm up. i have the relay and controller like in your picture thats mounted in the front by the starter solinoid. and i have a controller like this picture that has no wires.

 

For your transmission, check the fluid, change the filter if it needs it and you drop the pan. But for hard shifts,


1. Make sure you have a vacuum hose running from the firewall mounted block on the passenger side to the vacuum modulator.


2. If the vacuum hose is hooked up, and all seems fine, then replace the vacuum modulator. IIRC one bolt, loosen, pull out old, install new, tighten and put the vac hose on it.


BWD VM135 - Transmission Vacuum Modulator | O'Reilly Auto Parts

 

Follow all the glowplug wiring and find out what it's hooked to. It sounds like you have the older system and the solenoid on the pass side fender activates the system. If you follow the wiring from the glowplugs over and they end up on a large lug of a solenoid on the inner fender, then all you have to do is activate this solenoid, just like you would a starter solenoid.

Make sure it's fed with a large wire from the battery. Take a smaller wire from the battery, put a small fuse in the wire, and then run it into a pushbutton momentary switch that you mount in or under the dash somewhere. The run another wire back out and hook it to one of the small terminals on the glowplug solenoid. When you get it right, the solenoid should click when you push the switch. This should power the glowplugs.