so i bought an 86 f-350 about 3 weeks ago and it started great and ran like a champ for a couple days and then it died one day at a stop light. started right back up. then it would start to die more and more frequently until it just wouldnt start at all. i checked fuel pressure at the schrader valve next to the fuel filter and i was only getting a trickle of fuel as the engine attempted to turn over. ok, replace the mechanical pump. it ran great for a few days and then had the same problem again! so now i'm thinking that maybe there is debris in the fuel tank that is clogging the line. what do you all think?

also the last time it died when i attempted to restart, the wait to start light would not come on at all. i'm thinking the glow plug control switch is bad, or a fuse blew.

any opinions?

 

side or rear tank? the rear tanks have a problem where the pickup tube breaks or cracks and gets air in the system.

I used an electric pump on mine.. saves a lot of time if a return line goes bad and you have to re-prime.

glowplugs... I would start with the relay, then check the actual glow plugs, then the controller, they do go bad so i'm told.

 

its actually a flat bed with two tanks. i'll check the tubes regardless, if they didnt do a good job on the flatbed install i'm guessing that the pickup tubes would be more prone cracking anyway.

 

things to check:


pickup tubes inside the tank.
Tank switcher (sucking air)
return lines off the injectors (with elec pump you will see them leak)
0-rings on the return line caps
EDIT: check the water seperator, they are KNOWN to leak air into the system.

it WILL be a PITA to get it to fire if it runs dry using the mech pump since you have to crack the injector lines and bleed the air out.

on the glowplug isssue, it's possible for the relay to melt closed and burn them out all in one shot chances are the motor won't start without at least a few good ones from my experience, to check glowplugs with a meter set it to ohm's and check between the wire terminal and ground for each (with the wire disconnected). should read under 2ohms and will read infinite if it's bad.

 

updates??