O.K. I have replaced the glow plugs already and need to know all things that would make a diesel hard starting when cold only. After she gets warmed up, it starts up right away. In my owners manual, it says you can pump the fuel once or twice on warm days and a couple more times on cold days. This helps some but is still hard starting. What shall I do?

Ace


1989 Ford F250 4x4 7.3L

 

It sounds like the glow plug relay may need changing, or check the wiring to make sure that they are not frayed, thereby shorting out. I would need to know which truck you have to tell you where the Glow plug relay is..

Theo

 

Sorry theologian. I edited my first post with my truck info. How does one do a homeowner check on the glow plug relay for defectiveness?

 

Hi, I would check the cabling first, had the same sypmthom myself once, and found a cable on the relay was loose.
An ok relay with ok plugs will click on for about 10 seconds (WTS light on) , then cycle for a while. You will also see the voltage dropping heavily when this goes on.
Burnt out plugs or cable failure will make the relay to stay on too short, 3-4 secs. and the glowing will be unsufficient.

 

First thing to check is the glow plug relay controller.

On the '91 7.3L it is behind the airfilter at the back of the engine. I suspect the '89 7.3L is very similar.
Check the wires for broken, loose or corroded wires.
There is a few checks you can do on those connections, but I cannot remember them exactly. However they should be well documented around here. basically the checks are 'connect power to this, while touching this terminal - etc'. Like I said, I can't remember them exactly, so I don't want to mess you up any more for starting problems.

Next check is the starter and starter solenoid. With the hard starting condition, usually that solenoid gets burnt out. Have the starter checked at a shop, or just buy the rebuilt solenoid. (40 CDN vs a full 400 CDN for a starter).

Third check is the fuel filter. Check the pressure coming from the fuel filter valve while cranking. There should be a spray of diesel that comes out of that valve. Stand to the side, or where goggles, of course. Replace the filter just in case (35 CDN)

Fourth is batteries. They may be losing their charge, however after being started finally, they charge up enough while running to make it seem like it is easy starting after warmed up. Load test the batteries at a shop. It might suck, but replace the 'sub optimal' batteries, if they exist.

Fifth is injection pump. Might have a lot of crap in it (milky stuff and parts of 'rubber' floating). That needs to be clear of any particales, nad it is not cheap (950 CDN). That should be a last resort, however.

Like RayHell said, if the glow plug controller is working properly, you will hear it 'clicking' after the WTS light goes out. It should drop the voltage up and down in sequence with the 'clicking'. If that does NOT happen (voltage drop is the important thing here), then the controller is not working properly.

I have experienced ALL of the above at one time or another, and had to troubleshoot them all on my own vehicles. At this point, it is second nature for these checks on my trucks (except that glow plug controller check, I have only needed to do that once, and that was the problem).

I shudder when I think of buying a PSD, as I will have to learn a whole other set of checks...

 

OH< I forgot the most obvious thing...
WHen you cycle the glow plugs multiple times (3 or 4) is it easy starting?

I mean , turn the key on, let the WTS light go out, then turn key off. Repeat that 3 times, then last time turn the key over to start the vehicle.

IF it starts easy (or easier), it is the glow plugs or controller for the glow plugs. The reason is of course, they are not heating the fuel enouigh after a single WTS event, but after a few, they would have heated the fuel enough to let it ignite under compression.

The otehr thing I have heard for hard starting is water in the fuel that is PAST the fuel filter, but I have never experienced that yet myself. Water doesn't compress or ignite at all, and thus will create a hard start condition. (So I have read).

Let us know what your up to with this.

 

Could it be the transfer pump also?

 

Hey guys. This might sound crazy, but I'm just now getting back to my hard starting diesel truck. It's been sitting in my driveway for all this time and I only get to use it sparingly. So, I still have the hard starting issues, but now I've got other issues that aren't helping my situation at all. One, my batteries are now very low on juice from sitting all the time. Another thing is my ignition switch is acting up as well. When you turn it to the "On" position, it isn't quite far enough to get the WTS light to come on. You either have to turn it just a little more and hold it so it doesn't flip back to the "On" notch in the switch, or turn it back just a hair to find that special spot where the WTS light will come on. I bought another manual (Chiltons) because the Haynes doesn't have diesel engines in it. Can't find much on the stuff I need in the Chiltons manual either to help me troubleshoot. It just has lots of information on how to remove and install. I'm really getting frustrated with this truck as I have someone who wants to buy it but it's not running very good right now. Just so you know, after the posts above, I replaced the glow plug relay and nothing changed. The glow plugs were new when I started this thread back in the day, so I'm hoping it's not them. I'm also not hearing the clicking that I used to hear when the WTS light goes out. The dang relay is new but no clicks. *sigh* Any help would be greatly appreciated.

 

Sounds like you need to adjust the ignition switch first.

The actual switch is under the dash on top of the steering column.
There is a rod that runs from the key down to the switch, which have been known to break or bend.

Since the power to activate the glow plugs comes from the ignition circuit that opens the fuel shut off solenoid, if the glow plugs will not heat, the fuel shut off solenoid will not open either.

 

Hey Dave!

Hey, thanks for the info on the switch. I'll be looking at it tomorrow to see if I can find any problems. I'm also taking the batteries down to have them checked and buying new ones if the won't hold a good enough charge. Someone also suggested I drain the water separator as well as the fuel might be dirty or laden with water. I've got so many things to check, I don't know where to start! LOL! Well anyway, I'll let you know what I find. Again, thanks!

 

I just re read your first post.
Pumping the throttle on a diesel does nothing, except exercise your leg muscles.
There is no accelerator pump in fuel injection motors, those went out with carburetors.

Just depress the throttle 1/4 to 1/2 on warmer days while cranking till the engine fires.

 

O.K. I took the batteries in to be tested and the guy at the counter said I had 9 cranking amps out of 1000 on one and not much more on the other. The old batteries were 900 CCA and 1000 CA. I bought two new ones (Die Hard) with 850 cranking amps. Installed them and went to turn the truck over and it acted like I still had the old dead batteries in. I did a check to see if each battery was getting a good connection and they were. What could cause this? I'm at my wits end with this beast. Almost ready to give it away. Well, not really. I just don't have the time to spend fixing it and I have to get rid of the darn thing.

FOR SALE: Cheap '89 F-250 7.3L 4x4
New Batteries!