I have a '97 F-350 146,000 mi as the weather gets colder it has been more difficult to get started. I am not sure of the maintenance of the pickup because I have only had it about a year. I am thinking glow plugs going bad ( they might be originals) but today I took out fuel filter to check fuel level and it was almost empty after cranking on it A LOT which is making me think my fuel pump might be going or gone. In the past month or so I have noticed the fuel filter light coming on during hard acceleration up hill. I just changed filter recently too. the light goes out when you resume normal driving. Is this an indication of low pressure? if I put a gauge on fuel pressure during cranking will it help me diagnose fuel pump problem ( the pump is original I think).
I do not think it is CPS, the tach does move when cranking, it does not bounce but moves a little off zero.
Thanks

 

You can test the fuel pressure with a cheapo style stick tire gauge on the schrader valve on the drivers side of the fuel bowl.

You can also test the glow plugs. The outer pins on the 4 valve cover connections are the glow plugs. Two on each one. Test each to ground, should be right at or close to 1 ohm each.

You can also test the gpr. One big post should be hot all the time, the other should be hot when the key is on. With the key on, there should not be more than .3 volts difference between the big posts.

 

I didn't know the '97s had a fuel filter light. What does it look like?

Let's rule out fuel pump first. Hold open the drain valve on the fuel bowl, and have someone turn the key to ON without trying to start it. You should have a decent stream of fuel out the drain. Do you use some type of anti-gel?

To expand on Darin's post, the side of the relay that is hot on key-on will not stay hot for long. You may want to have someone turn the key for you while you hold the meter on the post. That way you can see if it comes on, and how long it stays hot.

 

The OBS PSD has a mechanical fuel pump. If you open the drain without starting the truck you'll get a stream of fuel but only until the filter bowl is empty. To pump fuel, the engine has to be spinning. That being said I think you are indeed dealing with a failing pump, or else you have an issue in the plumbing somewhere. It sounds like a pump to me though.

The Fuel Filter light is in the cluster to the right of the steering wheel and it says "Fuel Filter" when it lights up.

The glow plug relay will stay on for up to 2 minutes after you switch the key on depending on the temperature, so you should have time to get around to the front and get a meter or test light on it.

Darin won't steer you wrong

 

Clamp a jumper cable clamp on the two large posts on the GPR ( batteries fully charged ) , that by passes it . If it starts you need a new one . The fuel pump may not be able to keep up during extended cranking ..

 

OK, tested GPR, key off hot side 12.93v, key on, other terminal side 11.3v

 

What is the reading on the hot side with the key on? It will be less than 12.9. Need to know that.

 

Should be no higher than 12.6 key off or on ...Did you clamp a jumper cable clamp on the 2 large posts ?

 

I messed up a little and did the process with key off and got those readings so went ahead and replaced it anyway ( I bought one just in case). I still get no start.

 

Have you tested your fuel pressure and/or your gp's yet?

 

You STILL need to get the GPR reading 427_fordman asked about last night. Shoulda measured it before spending money on a new relay. "Replaced" doesn't mean "working". And +1 on the glow plugs; resistance should be aprx. 1 ohm each.

 

Key on hot side 11.92 Key on opposite term 11.8v, put fuel pressure guage on and get 0 pressure on cranking. Checked pins on valve cover gaskets and get no reading on both front pins and .o2 ohm on back two on passenger side. Have not done drivers side yet due to inner cooler pipes in way

 

Okay, GPR is good. Resistance readings sound strange. Test the meter - touch the two probes to each other, and it should read zero ohms. "No reading" usu means the circuit is open, i.e. infinite resistance. So those front plugs might be failed, or there may be a wiring issue under the valve cover. But super low resistance (it was def. .02, NOT 0.2, right?) means almost a dead short. .02 ohms at 12V translates to 600 amperes; that would be enough to fry the wiring almost all the way to the battery. Are you setting your meter on the lowest resistance setting, so it's reading single ohms, and not some power of ten?

 

It was fuel pump problem. Ordered new one from Riffraff Diesel, changed out and after some cranking she fired up and running. It just seems weird and lucky it broke down in my driveway. Glad it did it now instead of road trip for Christmas.

 

Sweet! I'm glad you got it up and running again. That banjo bolt is a real pain isn't it?