Jump to content

Do I need a new VP44?


Recommended Posts

Hey there guys... here's my situation.  After having no problems I parked in front of my work.  Came out for lunch and truck would not start.  This has never happened with this truck, always kicked right off.  I had my truck towed home, and trouble shot what I thought was the Raptor liftpump was inop, as no fuel was getting to the VP44.  Had them send me a new pump as this was in warranty, and I installed it yesterday.  I got the truck started, and thought everything was OK.  Went to drive it about an hour later and had to crank it for probably 20 seconds before it started rough, then smoothed out.  I was going to go into town with it, but as I was driving there I thought better of that and decided to drive it back home as maybe it wouldn't re-start.  Sure enough I got home, shut down and it wouldn't restart.  I troubleshot the Raptor, and discovered that it was not delivering fuel to the VP44 (FYI this happened several years ago with one of these pumps, stopped functioning within a day, so I had it in my head that this was the issue).  Cranked the engine over and felt for suction at the inlet of the Raptor, only suction was when the engine was cranking, i.e. the VP44 was pulling suction through the Raptor, and the Raptor wasn't working.  I should add that I could tell that the Raptor motor was running, could see and feel it.  So I called Indiana and they suggested I prime the Raptor with motor oil, which I did and did get it to pump fuel to the VP44.  I primed to the VP44 and could not get the truck started.  I have confirmed that there is fuel to the VP44 inlet, and have pulled the following codes: P1698, P0216, P1693, P0602, P1687, P1694, P0500. I know that some of these are thrown from using the Smarty, which I have set back to stock in the process of troubleshooting this.  After clearing the codes I again tried to prime the VP44 by Mikes process, cranking for 30 seconds at a time and then letting the starter cool off.  No Joy.  Checked for codes after this and have none.  I'm leaning to the theory that the fuel starvation caused by the Raptor not pumping has fried the VP44, and that when I started after first replacing the Raptor, the VP44 was pulling fuel through the Raptor and caused the failure.  I know there is a lot of experience with this stuff out there...can anyone shed some light on this before I go buy a rebuilt VP44?  Thanks

  • Like 1
Link to comment
Share on other sites

Hey there guys... here's my situation.  After having no problems I parked in front of my work.  Came out for lunch and truck would not start.  This has never happened with this truck, always kicked right off.  I had my truck towed home, and trouble shot what I thought was the Raptor liftpump was inop, as no fuel was getting to the VP44.  Had them send me a new pump as this was in warranty, and I installed it yesterday.  I got the truck started, and thought everything was OK.  Went to drive it about an hour later and had to crank it for probably 20 seconds before it started rough, then smoothed out.  I was going to go into town with it, but as I was driving there I thought better of that and decided to drive it back home as maybe it wouldn't re-start.  Sure enough I got home, shut down and it wouldn't restart.  I troubleshot the Raptor, and discovered that it was not delivering fuel to the VP44 (FYI this happened several years ago with one of these pumps, stopped functioning within a day, so I had it in my head that this was the issue).  Cranked the engine over and felt for suction at the inlet of the Raptor, only suction was when the engine was cranking, i.e. the VP44 was pulling suction through the Raptor, and the Raptor wasn't working.  I should add that I could tell that the Raptor motor was running, could see and feel it.  So I called Indiana and they suggested I prime the Raptor with motor oil, which I did and did get it to pump fuel to the VP44.  I primed to the VP44 and could not get the truck started.  I have confirmed that there is fuel to the VP44 inlet, and have pulled the following codes: P1698, P0216, P1693, P0602, P1687, P1694, P0500. I know that some of these are thrown from using the Smarty, which I have set back to stock in the process of troubleshooting this.  After clearing the codes I again tried to prime the VP44 by Mikes process, cranking for 30 seconds at a time and then letting the starter cool off.  No Joy.  Checked for codes after this and have none.  I'm leaning to the theory that the fuel starvation caused by the Raptor not pumping has fried the VP44, and that when I started after first replacing the Raptor, the VP44 was pulling fuel through the Raptor and caused the failure.  I know there is a lot of experience with this stuff out there...can anyone shed some light on this before I go buy a rebuilt VP44?  Thanks

 

I THINK YOU JUST HAVE AIR IN THE SYSTEM I COULD BE WRONG. ....BUT YOU NEED TO BLEED THE SYSTEM then you can eliminate the lift pump.....BY Mikes way  priming the Fuel system, Did you loosen each of the fuel lines at the head and banjo fitting at VP pump, then Bump starter only till you here raptor pump run for 20 seconds IIRC, repeat this process till you have fuel coming out around banjo fitting at VP. Then keep repeating process of cycling the lift pump by bumping starter till you get fuel coming from a fuel line at the head, as each line starts leaking fuel tighten it up,,repeat this process till all fuel lines have fuel coming out and have all been tightened..this should have all the air out of system

Edited by rburks
Link to comment
Share on other sites

  • Administrator

I would ensure you primed the whole system correctly before going any deeper.  Get fuel to the vp44 first, hotwire the airdog relay using a simple jumper between pins 30 and 87 of the relay.

 

Once you have fuel to the vp44 then crack the injection lines 1, 3 , 5 and start cranking.  Getting any fuel?  dont be afraid to crank for a minute.   It's not great for the starter, but it can be a PITA to get the system primed.

Link to comment
Share on other sites

Thanks all for the input.  I have verified that the Raptor (yes it's a FRRP) is running, it runs for about 20 secs. after bumping the starter.  I have cracked the VP44 inlet line and have observed fuel running from the fitting when the Raptor is operating.  I have cracked #1, #3, #4 and #5 injector lines at the injector, and observed only a trickle of fuel from #4.  What I will try this morning is jumpering the Raptor as per the suggestion of me78569 so the pump runs continuously, crack the inlet at the VP44 to get a good flow of fuel, tighten the inlet and crack the injector lines and see if that will prime it. Maybe it's just not priming?  I can hope so!

Link to comment
Share on other sites

Thanks all for the input.  I have verified that the Raptor (yes it's a FRRP) is running, it runs for about 20 secs. after bumping the starter.  I have cracked the VP44 inlet line and have observed fuel running from the fitting when the Raptor is operating.  I have cracked #1, #3, #4 and #5 injector lines at the injector, and observed only a trickle of fuel from #4.  What I will try this morning is jumpering the Raptor as per the suggestion of me78569 so the pump runs continuously, crack the inlet at the VP44 to get a good flow of fuel, tighten the inlet and crack the injector lines and see if that will prime it. Maybe it's just not priming?  I can hope so!

 

OK,  NOW THAT YOU SEE FUEL FROM#4 (trickle is all you should see just make sure its not sputtering air bubbles} tighten #4 and repeat the process, next one that trickles fuel tighten it up, only bumping starter to engage the lift pump. Im telling ya, there's a real good chance that thats all that is wrong is you have fuel lines air locked with air

these VP systems can be a beast to get started after lines have been opened up

  • Like 1
Link to comment
Share on other sites

  • Administrator

Only fuel from one port is rather scary. That means that possibly the rotor has broke free from the shaft internal on the injection pump. It could be air issues yet. So don't give up yet. I've seen rare cases where a shot of ether is all that is needed to get it to bump over. Before using starting fluid make sure to disconnect the grid heaters and only use a very small spurt of startering fluid.

  • Like 1
Link to comment
Share on other sites

These are all very good suggestions. I have bled mine more times than I care to count over the years and had good results with these methods but like stated above it can be a real pain sometimes. The second to last time I did it, it just would not prime and I did like Mike said and gave it a shot of juice and that was all it took. The last time I followed Blue Chips directions and although I did not agree with them at first it was the easiest priming I've had. Could have just been luck though as that seems to play a big role in it too.

Link to comment
Share on other sites

I did that, not 2-3 minutes of continuous cranking though, only about 30 secs at a time. I'll try longer when I jumper the relay this AM...

Look, your only gonna see fuel from one line especially at first till it starts pushing out all the Air,,,,AS soon as you see one line leeking, tighten it and bump starter to engage LP and wait for next one to seep....ITS EASY AS CRAP...IVE NEVER HAD THIS NOT WORK BUT be patient young grasshopper ...

IVE had to cycle the LP with the key 5-6 maybe 7 times when replacing VP pump to get fuel at 1st line seeping, eventually one line will pump up and the rest will follow suit..

 

   Now, if after this is done accurately and still no fuel to the other lines then you have other issues..and we can discuss that then...BUT unless you have deep pockets and don't mind throwing  parts at it, i suggest to following the troubleshooting procedures already stated above 

 

 

    Now I've never jumpered the LP fuel pump RELAY as NICK Suggested cause i never thought of it.  :shrug: .. but if you do this I WOULDN'T leave the LP running for extended periods of time cause during the LP pumps life cycle if doesn't see continuous operation for probably 20 sec. at a time when cranking... AND be DANG sure you get on the RIGHT pins.. #30 & #87. OR you could have problems that will make this one seem minimal..

Edited by rburks
Link to comment
Share on other sites

Okay, here's an update.  I cracked the inlet line to the VP44 and verified (again) that the Raptor was supplying fuel, it is.  Next I cracked 1,3,4 HP lines at the injectors.  Pulled the leads off of the grid heater.  Cranked over one minute, got no fuel at the injectors.  Cranked another minute, got a slight seepage at #4.  Tightened 4 and cranked again for another minute, nothing.  By this time my battery was getting low, so I decided to tighten the other two lines, and use some starting fluid.  Sprayed and obviously it ran until the fluid was used.  Sprayed a second time and this time the engine started to run on it's own.  I have let it run for about an hour and drove it around a bit to get the battery charged, and parked it and shut down.  I will go out in a while and see if it starts.  Geez, you guys weren't kidding about how much it takes to prime this!  The good news is that the VP44 must be at least functioning or the engine would never run.  I am still not feeling good about this until I get a few cold starts in without issue.

  • Like 2
Link to comment
Share on other sites

Okay, here's an update.  I cracked the inlet line to the VP44 and verified (again) that the Raptor was supplying fuel, it is.  Next I cracked 1,3,4 HP lines at the injectors.  Pulled the leads off of the grid heater.  Cranked over one minute, got no fuel at the injectors.  Cranked another minute, got a slight seepage at #4.  Tightened 4 and cranked again for another minute, nothing.  By this time my battery was getting low, so I decided to tighten the other two lines, and use some starting fluid.  Sprayed and obviously it ran until the fluid was used.  Sprayed a second time and this time the engine started to run on it's own.  I have let it run for about an hour and drove it around a bit to get the battery charged, and parked it and shut down.  I will go out in a while and see if it starts.  Geez, you guys weren't kidding about how much it takes to prime this!  The good news is that the VP44 must be at least functioning or the engine would never run.  I am still not feeling good about this until I get a few cold starts in without issue.

ID say your fine now,, don't underestimate what air in VP fuel system can do 

Link to comment
Share on other sites

OK here's the latest on this...just went out to start  and it took about 10 seconds of cranking before it started.  Running outside my house now, but I'm not sure how to proceed.  I guess I'll go to the store and see what happens.  Could the VP44 be losing it's prime?  Maybe the Raptor stopped pumping?  Don't know. 

Link to comment
Share on other sites

×
×
  • Create New...

Advertisements and Ad Blockers

Mopar1973Man.Com uses the income from advertisers to pay the bills on the website. Please whitelist your ad blockers for Mopar1973Man.Com this will allow advertisements to display on our pages but allows you to still block ads on the other websites you visit. 

 

image.png

I will whitelist Mopar1973Man.Com