Engine/Transmission (1998.5 - 2002) Rasp

[AHire]

With the rasp you have a back up pump and a dummy light to let you know the rasp is not pumping. What happens if the mechanical lift pump fails? Same thing that happens when the factory lift pump fails, VP44 gets starved for fuel.

 

[Silver Bullet Ram]

True, I agree with what you are saying, but the factory mechanical pump holds up better than the electric pump. Everything does wear out but some things last longer than others.



Gary

 

[GKinney]

pump swap

If I'm not mistaken with out looking it up in the manuals, doesn't the mechanical lift pump for the prior 24 valve engines produce a much higher fuel pressure??? I know high fuel pressure on the VP44 is about as harmful as low pressure. Just a thought.

 

[rweis]

Has anyone with a RASP still had VP failure?



I am about an inch from ordering a RASP, but do not want to only be substituting problems. I do have a DTT transmission and totally have faith in their products. The RASP was their solution to the lp problem.



I just had a VP replaced under warrantee (53k) and the mechanic at the dealership basically said LOTs of fuel AT 14 PSI to keep the VP running. As close as I can tell that is exactely what the RASP does.



What is the probably that the VP will run say 100k at at a clip before being replaced again and again and again and again with a RASP feeding it.



Bob Weis

 

[SnoKing]

Ok, I am on the road for 2 more weeks. I will get a RASP from "Power By Poole" when I get home. However while I am out here I would like to start planning the install.



What thread fittings are on the pump in and out?

What thread fittings are on the check valve ends?

The Hobbs switch is probably 1/4 NPT?

Can AN-6 handle the line size adequately? (350 hp)



Thanks, just planning ahead for the install.



Bob Weis



Has anyone with a RASP had to replace the VP-44 say more than 1 or 2 years later?



I thought I had the answer to the VP-44, but my truck is having a VP-44 replaced as I write this, so I did not have the answer. Apparently my steady 12 psi from a OEM lp was not enough (cooling?) flow to keep the electronics of the VP from failing. I think the RASP will push more volume consistently at 14 psi and increases its ability to pump with rpm rather than have to catch up with high demands as many electric pumps do (that is a whole different discussion for another time). Shutting down the OEM lp after engine start is a plus so you do not have to deal with the "flippen" check valve in the OEM lp.



I hope this is the last VP-44 I have to replace "on the road". At least Idid miss the hurricane (I'm from central FL).

Bob, I noticed that you have a 2002 truck. Someone should do a VP44 failure poll by truck years. Sure seems like I read about a lot of 2002 trucks having the pump fail! So maybe I will start the poll. SNOKING

 

[rweis]

Not sure HOW to do a poll.



I know the VP failure was a temperature thing. The dealer changed the camshaft position sensor. I knew that would not do it. I drove around town for a day. No 216. I took it out to the interstate 30 miles gently. No 216 (checked the codes twice on the way out). Drove it like I stole it on the way back. 216 almost immediately when I pushed 70 mph O/D out (high revs) pushed to WOT (85mph) from a standing still start. 216'ed as soon as I "gave her heck".



Dealer cleared the code and we went riding with the dealer test device thing.



Driven gently regardless of speed w/ O/D in (up to 85 mph), fine. Driven hard or turning high rpm's for more than 20 seconds or so, 216 code.



Could duplicate events over and over. Was an eye opener for mechanic. First time he was able to see the truck run HARD while using the scanner (normally they drive AND use the scanner) and duplicate the codes.



I think one of the reasons they replaced the VP. Duplicatable, verifiable, failure codes. He thought it was from VP electronics processing overheating and not from VP mechanics.



SO how do we keep the VP electronics happy? His only answer was REALLY GOOD fuel flow which the RASP will do. I just went to the DTT web site. The RASP has a 5 year warrantee on it as well.



I just want some feedback about the RASP and VP running for multiple years without failure. I know there are other reasons for VP failure, but I wouldlike some RASP guys to give some input about their RASP decision was good for the VP (of course everybody thinks their decisions are the correct ones).



I do feel the if BK ran it he probably ran the "heck" out of it before he endorsed it.



Wife feels the truck is "unreliable" with the VP failure after only 53k (and on a 3 week vacation, and 1100 miles from home). I need for the truck to become "reliable". She feels DTT transmission is "reliable" and "can" see that the RASP "could" be reliable. She understands electric motors failing (home electric dryer motor just failed after 3 years).



After I have put in about $10k getting the truck the way I want it (DTT transmission, DD2's, KSB1B, etc) I sure don't even want to think about "changing trucks".



Bob Weis

 

[BarryG]

Rwies:

Not that this will help but I just replaced my vp44 and had just put a rasp on a couple months ago. However my VP was starting its issue before the RASP install. I can let you know in a couple years. My vp history is about 70k per pump. On number 3 now. Sure hope the rasp helps.

 

[rweis]

I just had the lp and Vp replaced. I am going to call PBP this afternoon for the RASP. I am trusting BK on this one.



An interesting observation on the new lp. The electrical connector was different and had a adapter that plugged into the OEM harness. Also the new lp runs 16psi idle and pulls down to 14 psi heavy throttle unloaded and GENERALLY 14 psi heavily loaded.



Like they have changed the lp (different harness) and the psi is higher, 16 down to 14 under load.



Thanks for all the inputs, I'll sit on the sidelines for a while.



Bob Weis

 

[paulb]

I have about 45K on my RASP now. ~75K on the truck and still with the original VP44. You'll like the RASP.



Paul

 

[JR2]

I don't think the RASP has been around long enought to know if it will make your VP last for years, but I am certain its better that what you have now and will be way way more reliable.



As soon as I can round up enough nickles I will be getting one.

 

[Double J]

After I have put in about $10k getting the truck the way I want it (DTT transmission, DD2's, KSB1B, etc) I sure don't even want to think about "changing trucks".



Bob Weis

I know your feelings exactly... I was in the same boat your in not to long ago - minus the VP failure. I figured I've already sunk enough money into the truck that I'm in it for the long haul now so I better get the latest and greatest (IMHO) fuel delivery system on the market-get the RASP and forget about LP failures forever. I'm keeping my 01 for the long haul and the wife is getting a Mega Cab in a year or two (she just don't know it yet :-laf )



To be honest, my TDR surfing was cut in half after I went to the RASP... . now I spend time reading threads like "My Steering Sucks!" and simular threads

 

[rweis]

Well, those are good points. Certainly better than what I am relyig on now for sure Oo. .



Bob Weis

 

[rweis]

Ok, got the RASP and installed and a new VP fp sensor from Westach.



Question: What fp are you seeing and where are the readings pre ff or pre VP?



pre ff: I am seeing pre ff around town, ie some idle at stop lights, some 60 mph, all transmission gears, unloaded 16 psi - 20 psi.



pre VP: I am seeing pre VP around town, ie some idle at traffic light, some 60 mph, all transmission gears, unloaded 14 psi - 17 psi.



Is this what others are seeing?



I just want to check with others with RASP to see what they are reading and where in the system they are reading that psi.



Thanks,



Bob Weis

 

[DieselRam30]

I'm seeing around 14-16 psi all the time and I believe my readings were pre VP.

 

[rweis]

RASP is installed, towed the 5er for the first time with RASP. PERFECT!



2400 rpm / 60 mph O/D out 20psi on the pre ff, 17psi on the VP side.



One other thing a couple of us are experimenting with is cooling the VP. With slight excess pressure to the VP the VP bypass should be open and aid in the VP cooling. I have installed a fuel cooler w/fan on my VP/injector return line. I will start taking temp readings in a couple of days, but warm fuel back from the VP goes back into the tank as cooler by ?? degrees. Warm to the touch to not warm to the touch. Actual temps will be posted in a couple of days.



Bob Weis