Did you open the bleed screw? Did you pump the primer until you could barely push it down anymore? In my experience, 9 times out of 10, this type of problem comes back to a loss of prime.
LB7: Started up then died. Now engine wont start anymore.
- Thread starter Jeremy
- Start date
Did you open the bleed screw? Did you pump the primer until you could barely push it down anymore? In my experience, 9 times out of 10, this type of problem comes back to a loss of prime.
No I did not. I'll try that when I get home.
Another friend suggested to check the fuel filter for water? It did find it odd that I filled up the tank and then all of a sudden the next time I went to start it (even though it was days later) it had trouble starting.
Put an LML filter head on it, they dont have the heater in the top which is another source for leaks besides the plunger! Like Bryce said you have to re-route the fuel lines a bit but they work great for cheap. Also you can prime pump the sht out of your filter head and create 10-15 psi in the short side of the fuel supply and look for leaks. If you use the bleed screw make sure you remove all fuel residue from the area so its dry and you can see if fuel is seeping out any where!
So i went out when I got home and loosened the bleeder screw and primed the filter. After the fuel sprayed out, I started tightening the screw and noticed it felt weird. I pulled my socket off and the head of the bleeder screw came with it. And i am not the type to over torque stuff, so I'm wondering the if the bleeder screw was already cracked and coming apart? I didnt notice a fuel leak coming from the bleeder screw before I started playing with it so I guess it may be unrelated to my no start issue.
I noticed that someone made a comment about my batteries and terminals, the terminals are clean and tight and the truck cranks powerfully, just doesnt fire. So I dont think they're related to my no start issue, but if im wrong please correct me.
I am going to pick up a new bleeder screw for the filter head tomorrow, if I replace it and it doesnt work basically the suggestion is to replace the filter head with a replacement designed for an LML?
Thanks again guys.
I noticed that someone made a comment about my batteries and terminals, the terminals are clean and tight and the truck cranks powerfully, just doesnt fire. So I dont think they're related to my no start issue, but if im wrong please correct me.
I am going to pick up a new bleeder screw for the filter head tomorrow, if I replace it and it doesnt work basically the suggestion is to replace the filter head with a replacement designed for an LML?
Thanks again guys.
The filter heads for LLY's have been hard to get and on back order, The LML head is just another option. First rule about filter bleeding is dont touch the bleed screw.... Second rule of bleeding is dont ever use the bleed screw. Its absolutly not needed and is a major cause of start and die (loss of prime issues) Just try to pre-fill your fuel filter with fuel, if it is not possible to pre-fill you can still just install new filter, depress prime plunger 30-50 times smoothly then try to start, repeat till vehicle runs, 3-4 times average with dry filter, the factory lift pump will purge air from system, you will get the feel of the primer when fuel is finally present. Good luck.
LLY filter head p/n 12642623 with filter and sensor $160ish retail
Seems to be available now.
IMOP, it is not a good idea to pre fill a fuel filter. The stuff you are putting in is not filtered. I use the bleeder screws all the time with zero issues. It takes about 10 pumps and your done.
I was researching this thread and have a question. I have seen that some say only pump priming plunger three times or it will damage the filter head. Is this true for a 2003 LB7? Also I am having a similar issue. It has been starting hard when warm for a month now using the truck 2-3 times per week. Always started good cold (2-3 seconds). when warm could take up to 10 seconds maybe a little longer. Then this past weekend I replaced the fuel filter with an ac delco and had some trouble with the large o-ring but managed to get it to stay seated long enough to get the filter in place. Ran it for a test ride and got the same hard start. Then today while at idle (on busy road) it stalled. Thought I was going to have to have it towed but after considerable cranking and about 20 minutes time it started. started driving home and it stalled again as I was going down the highway but I pumped the throttle a couple of times and it took off. Managed to make it all the way home (about 40 miles). shut it off when i got home and started it right back up. I started it again a couple of hours later and it idle for about 2 minutes and stalled. now about 6 hours later it still wont start. Also I get a low fuel rail pressure code p1093. While cranking the engine my scan tool shows a frp of 229 ( I am assuming the units are Bars) which is about 3300 psi. Any ideas, thoughts, etc...
Well I replaced the broken bleeder screw today and tried to fire up the truck, still doesn't start. I have given the truck breaks in between each time I try to start it, and it has been unsuccessful.
Its so odd that it was doing the same thing on Saturday morning, then it ran perfect for a few days, and now it wont start again...
Any advice on what should be my next step? Replace the filter head?
Its so odd that it was doing the same thing on Saturday morning, then it ran perfect for a few days, and now it wont start again...
Any advice on what should be my next step? Replace the filter head?
Well you start with clean fuel and container and pour fuel into the side it enters from the tank, and waalaa no unfiltered fuel!
Well if your priming the system and getting fuel to the supply side of the pump you dont have a filter head problem.
So why not just dump your "clean" fuel in the tank, and say the Hell with the filter? Or put it on dry, open the bleeder screw, for its intended use, and pump the primer 10 times and be done with nice filtered fuel going through thousands worth of injection system.
I thought everybody just put the filter on dry turned the bleed screw and just turned the key on and the lift pump bleeds the air out for you,no pumping here,well as long as you have a lift pump i guess.i dont like pouring fuel straight into the filter either.
Makes sense. I guess im getting so frustrated with this im not using my head.
My next guess would be a sensor is going/has gone bad possibly?
Post where your from, and see if you can get a recommendation of some help in your area so you dont just start spending money.
Had this exact issue for 10 months now. Truck was once towed, dealership got it started, replaced some of the fuel lines etc. etc. It never did start good after the dealer had it and "fixed" it. Finally got tired of rolling the dice as to whether or not the truck would start and stay running because it finally stalled after 30 seconds and would not start again. This time I started with the basics fresh diesel, fuel filter to no avail. I removed the fuel filter head, 2 bolts, 2 fuel lines, 2 electrical connections. Took it apart, 3 torx screws for the plunger (one has a wire attached to it) and 2 torx screws on the bottom side and found that it was packed with dirt. I know this isn't good, but blew air through it to remove all the dirt that was blocking the fuel from getting through full time. Made sure it was spotless, reinstalled, primed it and it fired right up. It has been starting and running better than it has for months. Anyway, just one more "easy" and free thing to try. Worked for me.:woott: