truck wont stay running after rebuild
- Thread starter 6.4 Stroker
- Start date
broncof250444
New member
It would be due to a injector that's not torqued down correctly or the injector itself that's bad and the combustion gas it actually going threw the nozzle. seen this a few times. Also im sure you have checked fuel psi?
Also if you changed fuel filters during this did you snap the filter in the cap on primary filter? if not it will suck air around the o ring.
Also you need to get the bleeder tool that screws into the rear banjo that way you can start it with the bleeder in place and see of the truck stays running during this test.
6.4 Stroker
Member
I know Injectors are torqued down to spec. I checked them twice. I diden't changed fuel filters. I was gonna wait untill I got the truck running.
I have not checked fuel pressure yet. I'll make a gage and bleeder and see what it reads
6.4 Stroker
Member
Okay got some interesting findings.
I borrowed a bleeder from a friend and made fuel pressure guage.
With all the air out of the system "Key On Engine Off" fuel pressure read 6 psi. Right in spec. as soon as i turned over the engine the bleeder shot all sorts of air out and the gauge pressure went up with each RPM of the motor "like a compression test" up to 30 psi!!
I think Im on the right track.
I borrowed a bleeder from a friend and made fuel pressure guage.
With all the air out of the system "Key On Engine Off" fuel pressure read 6 psi. Right in spec. as soon as i turned over the engine the bleeder shot all sorts of air out and the gauge pressure went up with each RPM of the motor "like a compression test" up to 30 psi!!
I think Im on the right track.
broncof250444
New member
Sounds def like compression in the fuel..... Next will be hard to diag which side on that 6.4 but take the fuel lines off on the front of the heads and crank over with the "s" wire from the pass side fender well by air cleaner and see which side is building compression in the fuel system. Then tear that valve cover down to inspect.
so your saying it can go up the injector and basically push out of the return side coming out of the head?
I could def see an injector not getting torqued, not having the compression washer or having two washers...
I could def see an injector not getting torqued, not having the compression washer or having two washers...
6.4 Stroker
Member
Great!! Ill get this thing running yet! Thanks for the help guys! Ill post what i find tomorrow.
I have a feeling its a dumb mistake like that, :slap:
broncof250444
New member
Yep Ive had 1 6.4, 8-10 6.0's and 2 7.3's seen do where the injector had something broken inside which couldnt hold the needle down on the seat in the injector nozzle.
Lossen injector or double copper gasket is most common to see that problem tho.
6.4 Stroker
Member
Well guys, I found the problem #7 injecter was under torqued.
Bleed it again, started right up and I let it idol untill it warmed up all way then shut it off. This morning went go start and fired right up!
Thank you guys for all your help!! I would of had a hell of a time figuring it out on my own. Thanks!
Bleed it again, started right up and I let it idol untill it warmed up all way then shut it off. This morning went go start and fired right up!
Thank you guys for all your help!! I would of had a hell of a time figuring it out on my own. Thanks!
91turbogsx
Active member
Good to hear! Glad you found the issue and it was a simple one at that.
NoSlow6.0
New member
Not sure how the fuel systems compare vs the 6.0's as far as getting all the air purged out. But everytime I've ever broke the fuel system open or changed injectors on a 6.0 its at least an hour or more of cranking and dying and the spitting and sputtering for another half hour or so. It's always been a real pain in the A$$ trying to get it back running. Maybe you just need to hook up a battery charger or have a couple of spare batteries and just keep on trying that's the only way I've had any luck. I've not seen too many other people with this problem but its always been a sure thing with me.
Lassie
New member
???????????? After a head teardown even.....6.0's should take one crank cycle of 15 to 25 seconds until low pressure oil builds (HPOP res filled). After few minute rest for starter, another 15 second crank will fire it up.....rough for a few seconds and clear up. The fuel system will self prime with a few key on cycles too. This is typical of what I see.
Cool you found it good call on the injectors being not torqued I'll have to remember that
