Jump to content
  • Welcome To Mopar1973Man.Com LLC

    We are a privately owned support forum for the Dodge Ram Cummins Diesels. All information is free to read for everyone. To interact or ask questions you must have a subscription plan to enable all other features beyond reading. Please go over to the Subscription Page and pick out a plan that fits you best. At any time you wish to cancel the subscription please go back over to the Subscription Page and hit the Cancel button and your subscription will be stopped. All subscriptions are auto-renewing. 

is my vp44 shot


Recommended Posts

If u just changed the fuel pump and lines with old ones make sure none of them are leaking I’d hate for u to spend all that money and it be a simple thing like oring inside of aftermarket hoses or ur filter not being properly seated take the filter back off and make sure it is completely full

Link to comment
Share on other sites

If the raptor 100 has any air in it won’t pump to full pressure and will ruin itself if it isn’t full.. feel the pump after trying to run it if it’s super hot it isn’t any good hope u figure it out I’d also check ur pick up if it’s messed up and can’t draw properly 

Link to comment
Share on other sites

8 minutes ago, snoogett said:

If u just changed the fuel pump and lines with old ones make sure none of them are leaking I’d hate for u to spend all that money and it be a simple thing like oring inside of aftermarket hoses or ur filter not being properly seated take the filter back off and make sure it is completely full

i have checked for leaks, there are one. i am getting a weird sucking noise when the lift pump is running. its not constant but it sounds like there is air in the filter housing area, but i cant get it to not make that sound no matter how many times i bleed everything. i cant say i noticed it when the pump was on my other truck

Link to comment
Share on other sites

So probably need to take it back out and make sure there is no cracks in the aluminum plate that the hose fittings screw into.. sounds like you have found your problem u just need to figure out where it’s coming from.. maybe u have the  return hose and the tank hose swapped

Link to comment
Share on other sites

I replaced my pump motor several years and spent an hour and a half trying to get primed. That's the only time that it was that hard to get started. It did finally start and I never figured out why it was so stubborn that time.

 I would check over anything messed with on the install to be sure all is tight. 

 

  • Like 1
Link to comment
Share on other sites

U could take the line loose from the filter housing if it is still hooked up and fill it with diesel/ atf4 if u get someone else to fill it while u crack the hose on the to tank side maybe u can get it primed that would explain the sucking air noise it can get vapor locked just like any other pump

Link to comment
Share on other sites

when i took it off my other truck all i removed was the fitting going into the filter housing and the bolts holding it on the bracket. and then walked over and put the fitting in the back of the filter housing and clipped on the quick release fitting. so not fittings were removed out of the lift pump itself

dripley- i remember last time when i had to take the pump off to change the tappet cover gasket it took FOREVER to start but it finally did. but this time seems longer than before and like i said im not getting any fuel to 1,2,3 lines even after a dozen key bumps and 10+ 10 second cranks

Link to comment
Share on other sites

1 minute ago, snoogett said:

How much fuel did u let pour out cuz if u dumped it explains ur problem

If it’s past a certain point it cannot prime itself

pour out of where? dumped what? sorry im not understanding. ive primed these trucks dozens of times and never had an issue until now

Link to comment
Share on other sites

2 minutes ago, cumminsVP2001 said:

pour out of where? dumped what? sorry im not understanding. ive primed these trucks dozens of times and never had an issue until now

I apologize for the confusion when u removed the pump did any fuel come out of it? it has two places for fuel to come out sometimes three depending on your pump.. when u buy them new they usually have hydronic fluid or atf in them with the seals so they are already primed.. if u didn’t remove any fittings and it has no cracks or leaks there is really only two explanations left and that’s that the pump needs primed or is bad.. more than likely it just needs primed like dripley suggested.. also there is several locations for the pump for these yr models so may be why some of my suggestions are confusing to u. If u take the pump out and fill it all the way up with fuel or atf fluid before reinstalling it this will prime the pump and keep u from ruining it by sucking all that air through it

  • Like 1
Link to comment
Share on other sites

2 minutes ago, snoogett said:

I apologize for the confusion when u removed the pump did any fuel come out of it? it has two places for fuel to come out sometimes three depending on your pump.. when u buy them new they usually have hydronic fluid or atf in them with the seals so they are already primed.. if u didn’t remove any fittings and it has no cracks or leaks there is really only two explanations left and that’s that the pump needs primed or is bad.. more than likely it just needs primed like dripley suggested.. also there is several locations for the pump for these yr models so may be why some of my suggestions are confusing to u. If u take the pump out and fill it all the way up with fuel or atf fluid before reinstalling it this will prime the pump and keep u from ruining it by sucking all that air through it

even if im for sure getting good fuel to the vp? it can still not be primed?

Link to comment
Share on other sites

  • Staff
1 hour ago, cumminsVP2001 said:

i am getting a weird sucking noise when the lift pump is running.

Can you run the lift pump without starting or bumping the starter motor by hot wiring it?

Get the pump to run on demand by hot wiring it. 

Get a 3-4 foot piece of 5/16-3/8 hose. 

Start the fuel pump and using the hose like a stethoscope, with one end in your ear and the other moving along the fuel system, to detect the "sucking noise".   When you come to it, the sound will be loud and clear in your ear.  

 

Have you checked the flow of fuel after the fuel filter by placing a hose from the filter housing into a container  and running the pump?

Link to comment
Share on other sites

7 minutes ago, IBMobile said:

Can you run the lift pump without starting or bumping the starter motor by hot wiring it?

Get the pump to run on demand by hot wiring it. 

Get a 3-4 foot piece of 5/16-3/8 hose. 

Start the fuel pump and using the hose like a stethoscope, with one end in your ear and the other moving along the fuel system, to detect the "sucking noise".   When you come to it, the sound will be loud and clear in your ear.  

 

Have you checked the flow of fuel after the fuel filter by placing a hose from the filter housing into a container  and running the pump?

yes i have. i always do after a lift pump change

Link to comment
Share on other sites

Don’t know how loose you have 1,3 & 4 but after I installed new injectors I had to keep them a lot tighter then I did prior. Maybe get them a bit more snug and have someone crank while you turn them either tighter or looser. Before I used to have mine pretty loose and it would start and stumble along but the fittings were really loose, fuel would be spraying everywhere. Now they’re hand tight, bump once, then crank and it’ll start with pretty minimal fuel leaking. 

 

I know its not your your first time doing this but just throwin out ideas as I’m not sure why it’s this tough to get it primed all the sudden! 

Link to comment
Share on other sites

42 minutes ago, cumminsVP2001 said:

dripley- i remember last time when i had to take the pump off to change the tappet cover gasket it took FOREVER to start but it finally did. but this time seems longer than before and like i said im not getting any fuel to 1,2,3 lines even after a dozen key bumps and 10+ 10 second cranks

I lost count of how many I bumped the starter and cranked the engine after replacing the pump motor. Certainly way more than a dozen times. I did not have that hard of a time starting it after installing it new. If you have a a good heavy stream going to the VP I would not think it is the pump not being primed. You could shoot a little starter fluid and see if fires. Use it very sparingly. I would think it is warm enough out your way the grids wont come on. Might be an air  bubble in the VP.

Link to comment
Share on other sites

15 hours ago, dripley said:

I lost count of how many I bumped the starter and cranked the engine after replacing the pump motor. Certainly way more than a dozen times. I did not have that hard of a time starting it after installing it new. If you have a a good heavy stream going to the VP I would not think it is the pump not being primed. You could shoot a little starter fluid and see if fires. Use it very sparingly. I would think it is warm enough out your way the grids wont come on. Might be an air  bubble in the VP.

that was my next thought. can i spray a light mist over the intake runner or do i need to put the horn back on

16 hours ago, notlimah said:

Don’t know how loose you have 1,3 & 4 but after I installed new injectors I had to keep them a lot tighter then I did prior. Maybe get them a bit more snug and have someone crank while you turn them either tighter or looser. Before I used to have mine pretty loose and it would start and stumble along but the fittings were really loose, fuel would be spraying everywhere. Now they’re hand tight, bump once, then crank and it’ll start with pretty minimal fuel leaking. 

 

I know its not your your first time doing this but just throwin out ideas as I’m not sure why it’s this tough to get it primed all the sudden! 

for sure, i tr y to keep them as tight as i can while still getting fuel out because it does start to spray all over. i just put a airdog on my truck in the description and one bump to clear the lines out into a container, one ore bump while it was hooked up, crank for about 5 seconds and she fired right up

Link to comment
Share on other sites

×
×
  • Create New...