long cranking after AIRDOG INSTALL

[jasvan10]

I am having a longer cranking issuse then i ever experienced ,I just had a airdog installed and now have excessive cranking ,now I have exchange a few sentences with one of the mopar members here and this is what I just did, 1st> the truck sat all night, went out unpluged the airdog turned key to start and it fired up about a 1 second or less crank,turned it off right away, 2nd> I plugged the airdog back in and turned the key to start without waiting for pump to prime it took about 1 1/2 seconds to crank over, 3rd my truck is sitting in a driveway with the front faceing up hill when it started the 1st and 2nd time I drove it for about 13 miles and about 30 minutes 5 miles freeway the rest stop and go lights with the truck warmed up setting in driveway front end up again I shut it off and let set for about 15 minutes ,4th I went back outside and put the key in and turned to on position let airdog prime when it shut off I turned key to start it and it cranked for about 3 to 4 seconds before starting left it running for about 6 minutes turned it off ,5th I let truck set for about 25 to 30 minutes I unplugged airdog again turned key to start position and it fired right up 1 second or less.:banghead:

[Mopar1973Man]

If its firing up right away with the AirDog unplugged most likely you have a torn diagphram in the VP44 which makes it hyper-sensitive to the fuel pressure.What is your cranking fuel pressure like 10-12 PSI? Or is it more?

[AH64ID]

Is the AD wired thru a relay and the OEM pump wiring, or off of a 12V ignition source?

[jasvan10]

First I like to thank you for the responses ,I dont have the fuel pressure guage installed yet it is in trnsit as we speak I have owned this truck now for almost 14 years now and never had one, did not know of how important it is ,as for how it is wired ,the power source comes from the alternator and I assume that it is hooked into the ecm ,I never had this issue this severe till air dog install

[AH64ID]

I was looking for what trip's the relay to turn the pump on, the VP's don't like pressure at startup (which leads to long cranking).. or so I am told, and Michael will correct me if I am wrong.

[jasvan10]

I was just reading the AD installation guide and everything looks like its hooked up correct ,I also am looking for something thats simple since it is very excessive since install I was just trying to do a little pre maintenace and created a big problem

[dripley]

Welcome Jasvan, glad you came over. My AD's power also comes from the alternator to the AD relay. But another power source has to trip the realy. Thats what AH64ID is asking. My relay is fed from the alternator but the trigger comes from the oe wiring harness for the old lift pump. That harness is behind and below the fuel filter cannister. Check out the AD instructions, I believe they will show the harness and you can follow the wire from the relay to the source. Ill try and get you a picture of mine tomorrow.Is your FP gauge going to be in your hands soon? The fuel pressures would be very helpful and somewhat critical to diagnoseing the problem. The gauge would tell us whether you are connected to the ecm or an ignition source if you cant trace the wiring down.I forgot i already have a picture. Dont let the photo confues you because my filter canister is unbolted from the engine and my hand is where it should be, but the wires you see are the oe harness and the AD harness connected.

[jasvan10]

I ordered it 2 or 3 days ago so it probally I hope by tuesday , the hook up two the airdog went down under the old fuel canister and too the center of the block ,I got my big self under the truck and the connector looks like its plugged into to where the old connector was plugged ,yes I am seeing now the importance of this gauge I wish I would of registerd on these sites long ago ,I wasent untill I bought a 2008 Super duty with the 6.4 that I started visiting the diesel sites with the issuse I HAD with it but it was under warrenty now it gone, 4.5 years of that was enough

--- Update to the previous post...

Thanks Dripley, for directing me to this site the more folks I talk to the better off I will find the solution <I did go to blue chips web site and yes these pumps are pricey but if they are what he says they are then to me reliability is more important then looks ,this truck is my daily driver I work in the construction Industry and travel around a tri county area or more so its important that I fix it still cheaper than new

[hex0rz]

I'll throw my in here...If you can't figure it out by the time the new week comes, give AirDog a call and see if they can help you diagnose the problem. They should be able to give you some good help as well.

[dripley]

I ordered it 2 or 3 days ago so it probally I hope by tuesday , the hook up two the airdog went down under the old fuel canister and too the center of the block ,I got my big self under the truck and the connector looks like its plugged into to where the old connector was plugged ,yes I am seeing now the importance of this gauge I wish I would of registerd on these sites long ago ,I wasent untill I bought a 2008 Super duty with the 6.4 that I started visiting the diesel sites with the issuse I HAD with it but it was under warrenty now it gone, 4.5 years of that was enough

--- Update to the previous post...

Thanks Dripley, for directing me to this site the more folks I talk to the better off I will find the solution <I did go to blue chips web site and yes these pumps are pricey but if they are what he says they are then to me reliability is more important then looks ,this truck is my daily driver I work in the construction Industry and travel around a tri county area or more so its important that I fix it still cheaper than new

I know what you mean. I had my truck for quite a while before I knew of any of these forums. I pretty much stumbled around on my own picking up tid bits of info here and there and starting learning about the fuel pressure issues. When my ECM went out is when I starting learning about these forums and dabbling in them. I must say that the folks here at M1973M have by far been the most welcoming and helpful bunch of folks by far.

:cheers:Now all of you can take a bow. And a big ahearty thanks from one greatful member.

I did buy a Blue Chip pump after speaking with Chip. He is very knowledgeable about the pumps and I was convinced his was a better pump. I am not saying it isnt. I think the only way to ever know is to see how long it lasts. I am taking the same care of it as most of the folks here. Look around at some of the vendors here and talk to them. They sell good pumps to. How much better mine is than say one from DAP with a new computer is hard to say. Ther is no way I no of to compare one with the other since we dont know to what extent the pumps are built. Their are Bosch minimum standard that have to be met when rebuilding, but just how far beyond that someon takes it is an unknown, at least to me. Here is some thing to read on the subject. http://articles.mopar1973man.com/2nd-generation-24v-dodge-cummins/25-fuel-system/247-bosch-certified-vp44-injection-pump-rebuilders.

[jasvan10]

thanks for replyin ,Yes, I know that I have to figure out which pump rebuilder/retailer is going to give me the better value and I agree with you on what each puts into there rebuilds is how long they last and time will only tell ,I did called airdog on Friday and basicly he gave me a test to do and I perfomed one of them and that was to pull the power to the pump and see what happens and the second was to pinch one of the other lines I cant remember which one it was something about air being sucked into the pump , but he made it clear that he only interested in making sure the airdog was working correct which is understandable ,there was another test to make sure there was no air leaks was to pull the suction line off the tank put it into another fuel can with diesel and try to start the vehical that way and see what happens I seen that I blue chips site , I checked the fittings on the airdog but its hard to tell what happened in the tank itself

[dripley]

Try this, bunp the starter and then open the drain on the fuel canister. fuel should pour out as long as the pump is running. if it is pumping like mine you will get a flood of fuel. You can also remove the line from the vp and put it in a bucket and see how it flows, but this will let some air into the vp possibly causing you to have to open some injector lines to get the fuel back to the injectors. If it is pouring out of the drain you should not have to bleed the injectors. AH and MM are very good with this kind of stuff and will help fill in any blanks I might leave out.

[jasvan10]

thanks I am good at making a mess I will try that tomorrow

[dripley]

thanks I am good at making a mess I will try that tomorrow

So am I. I guess i should have paid attention to the 165gph before I turned it on with an open fuel line.

[DB Truck Customs]

I'll throw my in here... If you can't figure it out by the time the new week comes, give AirDog a call and see if they can help you diagnose the problem. They should be able to give you some good help as well.

Yes, AirDog has great customer service and could shed some light on it . My experiences with them have been great .

[jasvan10]

yes I will call AD again on wedensday or friday I should have my gauge installed by then .Dripley ,I did what you said I put a oil pan under the AD and bumped the starter the pump turned on I then opened the wing nut on the water seperator and the fuel did not come out as I would of suspected ,It came out in a steady stream without any preasure is that normal

[dripley]

When I told you that I was talking about the valve on the oe fuel canister. My AD is connected thru the oe canister. Yours probably is not. That was a personal choice of mine. I am not sure how big a stream of fuel will come thru the AD FW seperator. sorry about that. but it sounds like it is atleast pumping fuel. You could pull the fuel lin loose from the vp and see if you have a good stream there. definately get a bucket, it will push out alot of fuel if it is pumping properly. This will also let air into the vp which will have to be bled out to start the engin most likely. sometimes not, most times yes.

[jasvan10]

OH ,you know I was thinking about that last nite if it was ok to run it through the original filter canister to utilize the water in fuel sensor that is still hooked up and can you also use the filter in it also or would that be a restriction. After I bumped the starter and checked the flow coming into the seperator I closed it and tryied to start it and it would not turn over several cranks went on 3 times about about 4 seconds each before it turned over on the 4th try. YEP there is something wronge for sure I am going to wait till next week after I get my gauge installed before I buy a IP, and get familer with what has to come off and what tools I will need to get to do this change I guess if anyone is going to screw up my truck up its going to be me I tired of bringing it in for one thing and I always have bigger issuse after I get it back ,I will be in touch with all you thats help me, I thankyou again I will keep reading and keep trying to find the problem when I get my gauge I will chime back in :banghead:

[hex0rz]

The best thing to do is to take the line off that feeds the VP44. When you bump the engine and get the pump to run, opening the F/W sep. filter will not show you much. I think this will actually cause you to introduce air into the system and essentially will drain the pump area. The air should not go into the feed line though as the system has an air separator. This is just my theory though. :whistle:Taking off the supply line to the vp44 and putting it into a bucket will show you true flow of the AD. I personally run the supply line to the OEM fuel canister. There are many advantages to this IMO. There is another aspect of security you get passing the fuel through an extra filter, you can run your fuel pressure gauge off of it, you have use of the WIF light and it preheats the fuel.The only disadvantage to doing this is that the small steel line from the OEM canister to the vp44 is going to restrict flow. I'm going to look at doing a line between the vp44 and OEM canister like the airdog lines. This will increase the flow that is desired and also have the pressure needed.I agree with the idea of waiting until you have a FP gauge to get the info you need about what is doing what. It sounds like that you may have a problem with the vp44. I know that is something you dont want to hear, but it may very be that. The AD is functioning like it should. Although, the only other aspect to it is that the fuel pressure may be too high.You have failed to mention, or I have failed to see what AD you have. If you have a 100 or 150 I believe they have a coil spring with a ball for pressure regulation. The 165 is different. Do you have the AD2 or AD1 series?If you have an AD2 165, like me, you can always try what they recommend for setting fuel pressure. According to the book, you can screw the regulator in or out and then turn it whichever way so many times to have an approximate amount of fuel pressure.Just saying this just in case you might be interested in trying if you are adamant about working on it. You wont need very much at all to work on the AD, just a basic set of tools anyone should have if they are ever so mechanically inclined...

[dripley]

The best thing to do is to take the line off that feeds the VP44. When you bump the engine and get the pump to run, opening the F/W sep. filter will not show you much. I think this will actually cause you to introduce air into the system and essentially will drain the pump area. The air should not go into the feed line though as the system has an air separator. This is just my theory though. Taking off the supply line to the vp44 and putting it into a bucket will show you true flow of the AD. I personally run the supply line to the OEM fuel canister. There are many advantages to this IMO. There is another aspect of security you get passing the fuel through an extra filter, you can run your fuel pressure gauge off of it, you have use of the WIF light and it preheats the fuel. The only disadvantage to doing this is that the small steel line from the OEM canister to the vp44 is going to restrict flow. I'm going to look at doing a line between the vp44 and OEM canister like the airdog lines. This will increase the flow that is desired and also have the pressure needed. I agree with the idea of waiting until you have a FP gauge to get the info you need about what is doing what. It sounds like that you may have a problem with the vp44. I know that is something you dont want to hear, but it may very be that. The AD is functioning like it should. Although, the only other aspect to it is that the fuel pressure may be too high. You have failed to mention, or I have failed to see what AD you have. If you have a 100 or 150 I believe they have a coil spring with a ball for pressure regulation. The 165 is different. Do you have the AD2 or AD1 series? If you have an AD2 165, like me, you can always try what they recommend for setting fuel pressure. According to the book, you can screw the regulator in or out and then turn it whichever way so many times to have an approximate amount of fuel pressure. Just saying this just in case you might be interested in trying if you are adamant about working on it. You wont need very much at all to work on the AD, just a basic set of tools anyone should have if they are ever so mechanically inclined...

I have opened my drain on the oe canister with the ADII 165 running and it will spill some fuel. I was quite suprised at how much will come out. Since the system is sealed while doing this it will not introduce air while under pressure as long as you close the valve while the pump is runnig I installed a big line kit between the oe canister and the vp to eliminate the restrictive or fuel line. That is a must if you wish to used the oe canister. I tapped my FP gauge into this line. Jasvan told me has an ADII but it is not a 165 as i recall and they do make smaller flow ADII's. I am not sure if they have the pressure regulator like the 165 and he appears to be getting conflicting info from folks he has dealth with. Jasvan, which AD are you using? I cant remember.