Replaced Injection Pump and Mechanical Fuel Pump - Will not Start

Odin

Registered User
Joined
Sep 26, 2016
Posts
3
Reaction score
0
Location
Texas
I just got a 1988 F250 with the 7.3 IDI. When I bought it, it would start cold fine and ran great, however when it was hot it would not restart. I was told it was the injection pump. I bought a BWD reman pump from O'Reilly's and put it in. I got it running and drove it for about 30 min, on the way back to the house it shut off at a stoplight and would not restart.

I took it to a local shop and the replaced the mechanical fuel pump and it still won't start. The shop is telling me that the 2 day old injection pump is bad.

I am at a loss, is it possible that the new injection pump is bad? Is there something else that I need to look at? Any and all help would be appreciated.
 

DaveBen

Full Access Member
Joined
Sep 29, 2010
Posts
2,098
Reaction score
842
Location
Ukiah, Ca
YES it is possibly a bad pump. You should look at Conestoga Diesel for that pump. These guys are great and members here.
 

icanfixall

Official GMM hand model
Joined
Apr 10, 2005
Posts
25,858
Reaction score
682
Location
West coast
Welcome to the forum. Sadly you may have a bad injection pump. O'reilly's is not known for selling good pumps. This is why this forum has suggestions where to purchase known properly rebuilt injection pumps.
Can you tell us what the level of the fuel tanks were when this happened? Reason for asking this is these trucks fuel tank suction filter breaks off and that raises the suction level to about 1/4 tank. This means you show 1/4 tank of fuel but can't suck it out. Then sometimes this broken screen will plug the fuel tank switching valve so you can draw fuel from the tanks. For now lets hope the tank level is around 1/4. Thats an easy fix. Never let it get that low again.
 

Odin

Registered User
Joined
Sep 26, 2016
Posts
3
Reaction score
0
Location
Texas
I am not sure how much fuel was in the tanks, one of the things on the list to fix is the fuel gauge. It may have been that low.

I am going to get it back from the shop, top the tanks off, bleed the lines and charge the batteries and give it another go. I have a warranty on the pump so I can pull it and get it replaced.

Thank you for the responses, I will run through these things and let y'all know what I come up with.
 

OLDBULL8

Good Morning Ya'll.
Joined
Feb 12, 2009
Posts
9,923
Reaction score
342
Location
Delphos , Ohio
I gave you the same response about the tank fuel level on thedieselstop forum. trucker87 on there.

Welcome to the Oilburners, you will find more info and pictures if needed on here.

Here is your fuel gauge circuit.
 

Attachments

  • Fuel_ selector_wireing (2).jpg
    Fuel_ selector_wireing (2).jpg
    322.4 KB · Views: 18
  • Fuel_ selector_wireing.jpg
    Fuel_ selector_wireing.jpg
    511.2 KB · Views: 13

dgr

Full Access Member
Joined
Aug 5, 2012
Posts
915
Reaction score
238
Location
sac town
Depress your schraeder while cranking. If fuel sprays out, the lift pump is working. A clear hose on there will help you see if there is air in the supply side. If it does not spray fuel, either the lift pump is bad or the lift pump is not receiving fuel = blocked line or sucking air.

Turn on your key and then disconnect the wire to the top of the IP. You should be able to hear it close. Reconnect the wire. You should hear it open.

If the lift pump is providing fuel and the solenoid in the IP is functioning, crack all the lines at the injectors and crank the engine. It should dribble fuel out of the line nuts at the injectors.

When I need a new pump, I am going to order from one of OBNs vendors. But, I think some basic diagnosis should be performed first. Would be a sad thing to buy a new pump and find out the FSV valve is bad or you ran out of fuel.
 

Odin

Registered User
Joined
Sep 26, 2016
Posts
3
Reaction score
0
Location
Texas
Ok so after running through lots of options I gave in and took it to a mechanic in the area that works on and ownes an IDI. He had the truck for about 3 weeks and ran ever test he could think of and came to the conclusion that I had some rings stuck from it sitting before I bought it. It would start cold becuase everything was tight but once it had warmed up there was too much compression loss for it to turn over.

Not being one to give up I went to the local starter and alternator shop and bought a new World Power Systems starter that was for a CASE Frontend loader. With 2 new batteries, new cables and the new starter the truck starts with no problem now, hot or cold.

Just figured I would give an update and hope it helps someone else. For reference the starter shop said it is a 4 kW starter and it turns about twice as fast as the one that was in there.
 

Forum statistics

Threads
93,001
Posts
1,155,996
Members
26,589
Latest member
tke395

Members online

Top