Longer cranking...

[Dieselfuture]

30 minutes ago, Mopar1973Man said:

 

Injector o-rings would push fuel into the oil.

Crossover tube o-rings would leak fuel onto the manifold.

Can someone educate me, I thought orings were to keep oil out. And fuel is sealed off with copper to metal and metal to metal. But then again I forget a lot.

[Mopar1973Man]

The injector o-ring seals the fuel return from pumping into engine oil.

 

The copper shim is a multi-function part. It seals compression gases to fuel return, transfer heat from the injector tip into the coolant jacket and set the spray depth in the piston.

 

Crossover tube o-ring seals the return fuel rail from leaking on the manifold.

 

Little better?

[Dieselfuture]

1 hour ago, Mopar1973Man said:

 

Injector o-rings would push fuel into the oil.

Crossover tube o-rings would leak fuel onto the manifold.

Can someone educate me, I thought orings were to keep oil out. And fuel is sealed off with copper to metal and metal to metal. But then again I forget a lot.

Yes thank you, I think I knew that at one time. Seems it's a lot easier to ask then research, lol. Soon if not already most people will be dependant on someone else telling them how it is.

[notlimah]

11 hours ago, BIG-BLACK-DODGE said:

Following this... I have the same issue as you.

but i have a basically stock Airtex intank lift pump ( new).

I get a slight diesel fuel smell in the cab but every thing seems dry... 

You did tighten injector lines eh? Not sure if i read that u did that or not.

I was thinking it's my injector o-rings.

if so fuel would be in the oil correct? 

I took an oil sample but haven't sent it away yet. 

 

 

Yea injector lines are tight and completely dry. I'm 99% sure the issue is coming from somewhere in the return lines so that's why I'm replacing the grommets at the fuel T. 

[notlimah]

Quick update guys!

 

Well I got the 3 grommets replaced. I don't have to high of hopes of that being the problem as they all looked to be in pretty good shape.

 

 

Old grommets on top, new on bottom. I took a green pad to the T to clean it up a bit and sprayed it with brake clean then aired off. Got in reinstalled and pretty well snugged down. 

 

I then tackled my fittings at the VP inlet. I didn't like the way it was tightening down as it would cover my power steering fluid cap so I got a couple new fittings from Vulcan. 

 

I also wanted to check my T for my fuel pressure gauge just to make sure. It looks like it's possible the loctite didn't fully cure on the piece that connects the hose to the fittings so I'm letting that dry overnight.

 

 

If there was a slight leak there before, hope it's gone now. I'm also trying to find a better place to mount that needle valve so I can get to it easier, I'll be doing that tomorrow.

 

Also, does anyone see anything wrong with this?

 

 

Thats how far my needle valve sticks in my fuel T. Any flow issues or anything there?

 

Ill get everything out back together and primed tomorrow and let it sit as long as possible and see if my leak is gone.

 

[BIG-BLACK-DODGE]

On June 28, 2016 at 0:11 PM, notlimah said:

So just talked with Eric and he seems to think there's nothing really wrong. He said that even when parked on a hill with a completely sealed fuel system that gravity could still pull some fuel back. Either way he said that 5-8sec before starting isn't a huge concern and that I shouldn't worry about it. So just for my piece of mind I think I'll replace the T fitting grommets, replace the return banjo on the VP and replace the fittings for supply side of the VP. Eventually I'll replace the crossover tube O-rings, but that's just something I don't want to mess with right now. I'd like to wait until I can get some new injectors before replacing those.

 

Ha ya right!! That thing is not right! Period!!!!

lol that thing should fire imediately or very close to it...

So once it starts, u shut it off and it'll fire right up correct? 

I bump my key, the pump runs to 16psi then i start it and usually it fires instantly but some times it starts then stalls right away. Then i try to start again and she lights right away.

 

Did you consider the vp44 itself? That may be my issue too?? I have very high miles on mine (435,000km's) but i have stock intank lift pump. 

As soon as mine fires up it's good for the whole day.

You ride bulls for 8 seconds... U don't crank a cummins that long...?

So can u get your fuel pressure to 16 psi then try starting it? I'm not familiar with these fass/airdog lift pumps. 

On my truck if it's warmer out it starts almost instantly. I thought maybe it could be my rings are going less compresion etc but last winter i went out, fired it up then **** it off. Went in house 4 an hr, go outside and it fires right up... So for me it seems like it's just fuel bleeding back.

 

[notlimah]

I can bump the starter and get my fuel pressure up and then the truck will generally start up fine yes. The problem is, doing that isn't exactly the way I'd like to start the truck up every-time. I don't think it's the VP, all the symptoms I'm having point to leak in the return fuel lines or crossover tube o-ring, or worse case, leaking injector o-rings.

 

Just to recap what I've been dealing with

 

With the truck parked uphill...

 

-At key on, fuel pressure bump to 2-3psi with typical lift pump *brrrp*

-turn key to start and will crank for 5-8 seconds, first a small hicup/tried to start followed by a full start

-idles smooth, no excessive smoke, will run fine the rest of the day as long as not parked on steep slope up hill

generally takes about 4 hours parked in my driveway for it to start taking longer to fire up. Otherwise, insta-start

 

With the truck parked downhill...

 

-At key on, no fuel pressure bump and no lift pump *brrrp*

-truck will start almost immedietly

-idles smooth, no excessive smoke, will run/start fine the rest of the day except every start still wont have psi bump or lift pump sound.

[BIG-BLACK-DODGE]

On July 2, 2016 at 6:48 AM, JAG1 said:

BIG BLACK DODGE, what kind of fuel pressures do you see with the new intank lift pump?

 

The town talk is it needs to come out and get a different pump. Plus some other things to make it right.

Ha ha 435,000 km's running Edge Juice/attitude,air intake and MBRP 4" turbo back tells me the fuel pressure is just fine... Lots of towing too and all in the Rockies! 

 

I have 13-15 psi at idle and driving around town it's at 11-13 and on the hwy cruising it sit's around 9-11. Full throttle it goes down to 5 usually for a second then it comes up to 6-7psi. I know i know... That's just terrible for my injection pump... Lol but like i said 435,000 km's on this injection pump tells me it's just fine fuel presure. 

The Edge is usually always on 3 (Drive) and sometimes 4 ( race) and those pressures i gave are for mostly number 3.

It doesn't drop the pressure too much maybe 1psi from when i put it on stock setting. 

I was thinking of putting those BD oversize banjo bolts but i'm not sure if it'll drop my pressure... I wonder if when i stab the throttle and i see my fuel pressure drop to 6-8 psi if those larger banjo bolts would keep the presure up?? 

I looked all over and can't find anyone who did an experiment with those banjo bolts on stock lines and stock pump. 

Edited July 6, 2016 by BIG-BLACK-DODGE

[Me78569]

I noticed 0 improvement when I went with a big line kit.  Same pressure drop.  The lift pump simply cannot keep up.

[BIG-BLACK-DODGE]

oops

1 hour ago, notlimah said:

I can bump the starter and get my fuel pressure up and then the truck will generally start up fine yes. The problem is, doing that isn't exactly the way I'd like to start the truck up every-time. I don't think it's the VP, all the symptoms I'm having point to leak in the return fuel lines or crossover tube o-ring, or worse case, leaking injector o-rings.

 

Just to recap what I've been dealing with

 

With the truck parked uphill...

 

-At key on, fuel pressure bump to 2-3psi with typical lift pump *brrrp*

-turn key to start and will crank for 5-8 seconds, first a small hicup/tried to start followed by a full start

-idles smooth, no excessive smoke, will run fine the rest of the day as long as not parked on steep slope up hill

generally takes about 4 hours parked in my driveway for it to start taking longer to fire up. Otherwise, insta-start

 

With the truck parked downhill...

 

-At key on, no fuel pressure bump and no lift pump *brrrp*

-truck will start almost immedietly

-idles smooth, no excessive smoke, will run/start fine the rest of the day except every start still wont have psi bump or lift pump sound.

 

Yep i have the exact same issue but my truck starts up much faster than yours. 

I'm wondering if it's injector o-rings or even an injector bleeding down??

i better send that oil sample in before i was out a cylinder if it is injector issues....

also my truck is WAY over due for a valve set... I can't see that being it but never know. 

My truck used to do this intermitently...now it does it all the time. Same year trucks same issues... Lol

Edited July 6, 2016 by BIG-BLACK-DODGE

[notlimah]

I should have my oil checked next go around. I was kinda betting on it being grommets or washers gone bad but we'll see after this recent update on the grommets. From all the reading I've done, it's the crossover tube o-rings that are the last things changed, and typically end up fixing it if you've already replaced the washer at the back of the head and the grommets at the T and no fix.

 

I'll report back in the next few days to let you guys know if the grommets fixed it. I need to wait for the air to bleed out of my fuel pressure gauge lines. I'm seeing sporadic pressures right now, same as I did before when I installed the gauge.

 

As far as my fuel pressures, when all the lines are bled and everything's running warm. I never see below 17psi and typically see 17-18psi at all times. Those pressures are low, but like you said, that's a long time for the pump to still be rollin on pressure like that. My 99 is at 170k and stock VP and for majority of it's life was running on stock lift pump and she's still running strong as ever!

[BIG-BLACK-DODGE]

36 minutes ago, Me78569 said:

I noticed 0 improvement when I went with a big line kit.  Same pressure drop.  The lift pump simply cannot keep up.

 

So big line kit on a stock brand new pump? 

And you left the stock size banjo bolts or changed them all to ones with bigger holes?

13 minutes ago, notlimah said:

I should have my oil checked next go around. I was kinda betting on it being grommets or washers gone bad but we'll see after this recent update on the grommets. From all the reading I've done, it's the crossover tube o-rings that are the last things changed, and typically end up fixing it if you've already replaced the washer at the back of the head and the grommets at the T and no fix.

 

I'll report back in the next few days to let you guys know if the grommets fixed it. I need to wait for the air to bleed out of my fuel pressure gauge lines. I'm seeing sporadic pressures right now, same as I did before when I installed the gauge.

 

As far as my fuel pressures, when all the lines are bled and everything's running warm. I never see below 17psi and typically see 17-18psi at all times. Those pressures are low, but like you said, that's a long time for the pump to still be rollin on pressure like that. My 99 is at 170k and stock VP and for majority of it's life was running on stock lift pump and she's still running strong as ever!

 

Yep i'm fairly new to the Cummins world and the vp44's but i read a TON of literature and i just don't buy this big presure thing. Sure maybe with big turbo and injectors but not stock.  Same with the 14 plus psi need to cool the pump, i don't agree with that either. I think you just end up heating up the fuel in the tank more...

moparman is going to hate me for this lol. 

So on your speratic fuel pressures, is that an electric gauge? My edge was bouncing all over the place for fuel pressure and i have the alarm set for 4psi and it was going off like crazy. 

Ended up being a bad conection on the fuel pressure sender for the Edge. I unpluged and pluged back in. Good for a month them happened again. This time input dialectric grease on the plug and she's fixed for good. 

Edited July 6, 2016 by BIG-BLACK-DODGE

[JAG1]

4 hours ago, Me78569 said:

I noticed 0 improvement when I went with a big line kit.  Same pressure drop.  The lift pump simply cannot keep up.

I went to 1/2'' lines with the same stock carter lift pump installed down on the frame and it made a big difference. It made me very happy to have met Eric at Vulcan as it was an amazing change for the better.

 

Boss Hogg, Do they make you run the ULSD like here in the states?

[notlimah]

I definitely think 14psi is needed to cool the pump and I don't think it matters whether it's stock or highly modded truck. Although, there are some cases like yours and mine where the pump just seems to run for a lot longer then it seems it should but I think these cases are a lot more few and far between. 

 

My fuel pressure gauge is mechanical. It did this the last time I opened the fuel lines. Took a little bit of driving before all the air got out and the needle stayed rock solid from then on.

[BIG-BLACK-DODGE]

7 hours ago, JAG1 said:

I went to 1/2'' lines with the same stock carter lift pump installed down on the frame and it made a big difference. It made me very happy to have met Eric at Vulcan as it was an amazing change for the better.

 

Boss Hogg, Do they make you run the ULSD like here in the states?

I don't think so. I do see ULSD signs on some of the pumps. I'll have to look into that more. 

And what differences did you see in pressures? Higher pressures or just more stabilized and not droping so much?

3 hours ago, notlimah said:

I definitely think 14psi is needed to cool the pump and I don't think it matters whether it's stock or highly modded truck. Although, there are some cases like yours and mine where the pump just seems to run for a lot longer then it seems it should but I think these cases are a lot more few and far between. 

 

My fuel pressure gauge is mechanical. It did this the last time I opened the fuel lines. Took a little bit of driving before all the air got out and the needle stayed rock solid from then on.

My theory is if you constantly pump fuel through that pump and back to the tank, eventually the fuel in the tank will become warmer because you are pumping it through a hot pump. . Not a big deal on short trips but on long hauls i could see it heating the fuel more. 

We should start a thread asking what peoples fuel temps are. I'd like to hear what everyone elses is. 

And another reason why maybe my Injection pump has lasted so long is my truck is a 6 speed and when i let off the throttle to shift gears the pressure jumps up everytime where as on an automatic trany maybe it would drop my pressures longer???

also I have the H.O pump. Did thecauto's come with H.O pumps?? Maybe that plays a roll. ???

 

Edited July 6, 2016 by BIG-BLACK-DODGE

[dripley]

HO's only came in the 6 speeds. 

[leathermaneod]

I would like to know fuel temps as well, because I too believe that the fuel is heated. Especially on long trips and especially when the tank is near empty. Problem is, not that many guys have the ability to monitor fuel temp. 

[notlimah]

I saw FASS setup to read fuel temps on a 4th gen I believe but it was showing how well their fuel heater worked.

 

The way how I understand the VP44 overflow valve working is that it wont be cycling fuel through the pump to cool it unless its at 14psi or higher. Otherwise fuel is just flowing through the pump to supply the engine as needed.

 

I do agree that on a low tank of fuel or longer trips that fuel will get warmer then shorter trips with high fuel tank levels, but even the fuel leaving the engine and going back to the tank and then directly back to the VP would cool off quite a bit I'd imagine.

[dripley]

14 PSI is where the overflow is fully open. Some fuel constantly flows thru for cooling. That is my understanding. Someone correct if I am wrong.

[Me78569]

The quadzilla reads fuel temp. 

 

my fuel temp in the vp44 is always ~15-30*f over ambient regardless of how long you drive.  the tank acts as a good heat sink.