I just got done replacing all the caps, o-rings, and return fuel lines. I also had to put in a new injector and #5 injector line. Oh, and had to replace 2 gps. Went to start is am and it kind of started then stoped. I had to crank and crank forever before it stumbled and finally started. The return line kit i used was one i bought off ebay, maybe those are not good quality?? I spun the fuel filter off to see if it was full or had a bunch of air in it. to my surprise no air, i actually heard it suck air thought the oneway flapper valve. Alos somone said there is a olive nut behind the #8 injector. the only thing i can find is a place where 3 return lines meet. My truck starts worse now thatn it did before the return line kit. I also took the fuel to ip supply line off. I am at a loss as to where air is getting ??? Please help!!
Super Hard start after repairs
- Thread starter seacow
- Start date
Goofyexponent
Mentally Unstable..
I would highly reccomend talking to TYP4 about his return line kit. I ALMOST bought the kit from ebay, but TYP4's kit is WAY nicer and he's great to deal with!
icanfixall
Official GMM hand model
You found the place near the #8 injector that has the olive gasket in it. Remove that entire line off the motor to repair or replace the gasket. Its just that easy. How long did you run the motor... Did you get all the air purged from the pump and system. These motors run ruff after the fuel system is opened for repairs but... It will purge out. Air your glow plugs working... I had a hard start issue I thought was my Moose pump failing... So I changed it out for a spare pump from Pensacola pumps... Still had the hard start issue. Found the problem was the power supply line to the controller was in two pieces... I had made this wire myself and the soldiered lug at the controller didn't take... I still had a wait to start lite the same amount of time as before this issue... I just didn't have any glows that were working.... Resoldiered it and its starts in 1/4 turn of the motor... But again, it seemed like I had a fuel-air issue because it was so hard to start and it would run ruf for about 15 seconds... Funny how much these motors depend on a glow plug to lite them off cold...
icanfixall
Official GMM hand model
It really sounds like your glow plugs are not working. Did any of them get the connections bumped while doing the work you did... Why did you remove all the hard lines and did you reinstal the vibration line dampners....
I had to remove all the hard lines to get to the #2 and 7 lines they were leaking a lil bit and i also figured that with them out of the way make it a little bit easier to do the caps. And yes vibration clamps back on in their original positions, I wont even try to start it without those. it acts as if i have no fuel or major air leak, before this i had 2 gps burned out and it would at least fire with abou 1/4 turn of the motor, its as if the injector pump is leaking down.
It kind of fired, and then it just spun and spun until it finally started and then it ran like crap for a about a minute. Shaking sputtering and blowing gray/black smoke and some white. I really gotta get this diagnosed and fixed before a take a starter out.
benwill1
94Ecabfaciditrb4x4
After I replaced my return lines and caps, it took a month or so before it would start-up without turning over several seconds. I think the new caps and o-rings take a little bit of running to seal good enough to prevent air from entering the system? give it a few days..maybe a week. They will leak air in, without leaking fuel out...belive it or not.
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yes it definatly sounds like air intrushion. are you sure the caps are all the way down? ive also seen people when they replace the hose in between the caps either cut them to short or to long and it puts a bind on the caps and causes them to leak air in. also how does the olive seals on the main line coming from the filter housing to the ip look. i tell you to check this closly because i just went through this. i put new caps and hoses and it still was hard to start. the way i found that the olive seals were leaking was i saw a drop of fuel leak while the motor was running and it had been dripping so long that it had actualy cleaned a spot on the intake gasket. hope you get it fixed and have a merry christmas.
jim x 3
1988 F-350 DRW
Sea,
Assuming your engine is like my 1988 7.3, also check your electrical connection to the temperature switch just in front of #1 cylinder (behind the upper coolant hose). If the electrical connection got disturbed while working your fuel system (which is possible because the wires are in the GP harness) then you don't have a functioning cold timing advance (CTA) and Fast Idle (FIS).
So your warm starts would be fine, but cold starts would suffer as you described.
You can check that the electrical connection is in place by going Key ON, set the throttle, then check the FIS to see if its set.
Regards,
Assuming your engine is like my 1988 7.3, also check your electrical connection to the temperature switch just in front of #1 cylinder (behind the upper coolant hose). If the electrical connection got disturbed while working your fuel system (which is possible because the wires are in the GP harness) then you don't have a functioning cold timing advance (CTA) and Fast Idle (FIS).
So your warm starts would be fine, but cold starts would suffer as you described.
You can check that the electrical connection is in place by going Key ON, set the throttle, then check the FIS to see if its set.
Regards,
How do I check the FIS? My truck does kick up to high idle after it starts and i give the pedal a little tap. Also is am i plugged it in and it started right up just one little puff of smoke and that was it. So wierd? i think i am going to have to dig in and check the glow plugs maybe I smoked a couple with all that cranking and maybe my controller as well seeing how it burns maybe 9 secs first time and then not even 2 secs after that?? Any Ideas?
LCAM-01XA
Full Access Member
Seacow, the fire then die you're experiencing is definitely an air intrusion issue. However, the caps and o-rings ain't all that sensitive as everyone is making them out to be - ALL my hoses are cut a bit too long and kinda weave between the injector caps and I have no leaks whatsoever. Also I once had to remove the line off the #7 injector while in a truck stop so I can tighten the injector down in the head, during this I apparently cocked the cap and when I fired up the truck it was dripping fuel - I simply wiggled the cap a bit and the o-ring seated again and it's soon to be an year since then with no issues whatsoever. I'm using a GP Sorensen kit that the PO had left for me under the seat of the truck when I got it...
Also, I will have to disagree with what Jim says - I sometimes have to fire up my truck on low idle so I don't wake up the neighborhood, she starts up just fine in cold and stays running - granted she rattles a lot and for the first minute slightly misfires, but she stays running and I can drive her immediately. So the solenoids ain't your issue, and neither are your GPs.
I'd suggest that you look into the main return line from the engine back down to the frame rail, that started leaking on me last fall it it took me like a week to figure it out - after replacing the rubber hose there I also removed the return hose from the filter head, I have since then had the heater o-ring develop a leak but since it is at the highest point of the filter head and there's no return line there no more it couldn't drain my filter, and I was starting just fine, only making a mess while running.
On the olive donut behind the #8 injector - not all trucks have that, mine for instance don't - you will only have it if you have a large steel return line coming off your IP and running on the driver side of the intake under all the injector pressure lines. Trucks with that setup also have a cap on the #2 injector with only one port, and there's just one return hose hooked up to it, leading to the #4 injector. For comparison my truck has no IP steel return line, instead the IP return flow passes through the #2 injector cap (the cap has two ports at 90 degrees from each other), and then passes through all the driver-side injectors till it reaches the rear of the engine. I suspect this is why I have the 1/4" return lines, an not the 3/16" that is typical for the '6.9 trucks that also have the steel IP line - the injector return lines in my case have to handle the flow from both the IP and the injectors themselves. This is actually a factory setup, I haven't modified it at all, other than when I removed the return line from the filter head I ran its hose from the # injector to the IP return port (with a Tee fitting) so now the IP split its return flow through both banks of injectors - they still Tee together in the rear of the engine and from there down it's one main rubber line (the one that was leaking on me last fall).
Also, I will have to disagree with what Jim says - I sometimes have to fire up my truck on low idle so I don't wake up the neighborhood, she starts up just fine in cold and stays running - granted she rattles a lot and for the first minute slightly misfires, but she stays running and I can drive her immediately. So the solenoids ain't your issue, and neither are your GPs.
I'd suggest that you look into the main return line from the engine back down to the frame rail, that started leaking on me last fall it it took me like a week to figure it out - after replacing the rubber hose there I also removed the return hose from the filter head, I have since then had the heater o-ring develop a leak but since it is at the highest point of the filter head and there's no return line there no more it couldn't drain my filter, and I was starting just fine, only making a mess while running.
On the olive donut behind the #8 injector - not all trucks have that, mine for instance don't - you will only have it if you have a large steel return line coming off your IP and running on the driver side of the intake under all the injector pressure lines. Trucks with that setup also have a cap on the #2 injector with only one port, and there's just one return hose hooked up to it, leading to the #4 injector. For comparison my truck has no IP steel return line, instead the IP return flow passes through the #2 injector cap (the cap has two ports at 90 degrees from each other), and then passes through all the driver-side injectors till it reaches the rear of the engine. I suspect this is why I have the 1/4" return lines, an not the 3/16" that is typical for the '6.9 trucks that also have the steel IP line - the injector return lines in my case have to handle the flow from both the IP and the injectors themselves. This is actually a factory setup, I haven't modified it at all, other than when I removed the return line from the filter head I ran its hose from the # injector to the IP return port (with a Tee fitting) so now the IP split its return flow through both banks of injectors - they still Tee together in the rear of the engine and from there down it's one main rubber line (the one that was leaking on me last fall).
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What i dont get if its air intrusion then how come when its not plugged it starts really hard, but this am i plugged it in, and it fired rightup with no stumble? Shouldnt it have stummbled this morning too if it was getting air into it?? Starts hard with no preheat and starts great with preheat? I am at a loss?
Alex S
Jeoff
sounds like a GP problem, or are you holding the gas peddle down at all when you start?
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