Hi all
This is my 1st ford truck,owned it 3 months now, when i got it the fuel filter was leaking so i replaced it, I've done around 2800 miles since then, I was on the motorway (UK) friday doing around 75mph when the fuel filter light came on, within minutes the truck was loosing power so i pulled off onto quieter roads, within another mile the motor cut out, I had a new filter behind the seat so i filled it with diesel and fitted it, got the air bled out and set off again,drove 2 mins to a petrol station and filled the rear tank with Diesel then switched to that just in case the fuel in the front tank was contaminated, Truck ran fine for next 5 mins or so until the filter light came on again, the motor was surging and running rough I managed to limp to the Girlfriends house where the truck cut out and will not start again, any ideas where to start looking?

 

How long had the truck sat before you bought it. Old diesel can form algae that will plug fuel filters. Adding fresh diesel helps but at the same time it cleans the contamination out of the tank and pumps it through your fuel filter plugging it again. Another thing to check after puting a fresh filter on is for fuel pressure. There should be a schroeder valve on the filter head that you can attatch a gauge to. If the reading is less than 4 or 5 psi it could be a sign of a failing lift pump.

 

The truck was in regular use when i bought it plus i've done close to 3000 miles since owning it, I just looked in the old filter and it looks really clean, the rear tank was empty too, i've not used it for a couple of weeks now so put fresh fuel in that one to see if it helped but not. Will i get the correct fuel pressure on the gauge you suggest cranking the motor as it wont run at all now

 

yes, if it won't run cranking may be the only way to see. I just re-read and seen the surging part. This could be an indication of major air intrusion from either rusty fuel lines or rotten rubber lines. The easiest way to tell is to look through at the entire system and see if lines are wet with fuel, if fuel gets out, air can get in. The most common area is the plastic return line caps that run between the injectors, but on my last 7.3 it was because the metal fuel lines coming out of the fuel tank had rusted quite badly. It would run fine under light load but if any work was required of it it would surge every time.

 

The filter light coming on is telling you that the sensor is detecting a vaccume in the system, meaning there is no fuel getting threw the filter. A dirty, plugged filter is usually the cause. Sense 75dually has changed the filter, and is getting the same thing happening, a fuel pressure and flow test is in order. 5-7 lbs. of pressure at the schrader valve while cranking, and 1/3 pint from the schrader valve, with core removed, and no air bubbles, in 10 seconds of cranking is what is needed. If either test fails, most probable cause is a faulty lift pump.

 

Got truck transported home, charged batteries and i have 3 to 3.5 psi fuel pressure at the fuel filter, it's running again now and the filter light is out now, darn't drive it as not many recovery vehicles around here big enough to bring it home if it dies again, is it likely to be the lift pump on it's way out rather than a blockage? Just looked on rockauto, $22 for the pump and $53 to ship it not many places will ship to the UK???

 

More than likely The lift pump is on the way out. Some people convert to an electric fuel pump, which should be readily available over there. A low pressure, low volume pump is what you need. If you decide to convert to an electric pump, by pass the pump that is on there, or remove it, and use a block off plate for a chevy motor to cover the spot where the original pump is located. Several members have used an electric pump used on refrigerated tractor-trailers, as they are designed to pull fuel up to 10 feet. Most pumps push fuel better than the can pull it.

 

Just found an electric pump on ebay, pumps 40 gal per hour at 6-8 psi, our gallons are a bit bigger than your though. Am i allowed to post ebay listing on here?

 

Yes, you can post the link to the listing.

 

Will this pump be ok?

12 Volt Electric , Electronic Fuel pump , | eBay

 

I haven't seen that brand over here, but I think it would work all right, although the volume is more than needed.

 

The electric I bought, specifically stated it was for "diesel" on it.
I don't know if that makes a difference, but just saying.

 

Right it finally stopped raining long enough to work on the truck, I temporarily fitted the electric pump on the frame rail down near the mech pump so the lines would reach, now at the schrader valve i get 2.5 psi with the pump running and 0.5psi with the motor running??? So I took the fuel line off to the IP and checked the pressure there and it's just over 4psi, seems to run fine, gear changes feel sharper than they ever did, think i'll leave it as it is and see how it goes now