Why has'nt cummins droped the lift pump idea and went to a pusher pump ?? FORD DID!

[DieselMinded]

With all the trouble in the cummins world of lift pump failures then shorty after injector pumps why do cummins stay with the design. . even in some older CTD Ive seen people put electronic fuel pumps in line to help the lift pump and now rasp and fass ... I mean common already drop the lift pump get a pusher pump . Whats the benifit of a lift pump compared to a pusher pump???? CTD AFTER MARKET SALES?????Theres got to be something good about it> I think in '97 ford switched to a pusher .

DM

 

[WMonroe]

The 2005 Rams have the pump in the tank now.

Will

 

[RustyJC]

The 2005 Rams have the pump in the tank now.

Will

I'm not sure if this is good news or bad news. If the pumps live, it will be fine. If they don't, we'll be dropping tanks on the side of the road to change transfer (lift) pumps.



Rusty

 

[A Johnson]

I allways thought a factory pusher would be a good idea. I'm not smart enough to understand why a fuel injected gasser can use a pump in the tank but the ISB can't. Seems understandable that DC would use the sucker pump on the 98. 5 model year but then after all the issues they should have designed the tank module with a pump in it and purchased the engine without a lift pump from Cummins.



Keep in mind that the ISB is put in so many different applications that it needs a transfer pump on the engine so it is sellable to smaller OEM's. Also I think it would be possible to just put a bump on the camshaft and run a diaphram type pump like the pre 94 engines. The 12 valve 6BT Tier 2 industrial engine uses a diaphram pump with the VP-30, but the from what I understand the VP-30 has different internals than the VP-44, more like a VE pump I think.



A Johnson

 

[HoleshotHolset]

Also I think it would be possible to just put a bump on the camshaft and run a diaphram type pump like the pre 94 engines.

This style of lift pump arrangement (with minor changes... ) lasted from '89 until '98. 4 on the Cumminses. I see what you mean about the pre-Powerstroke IDI's - those lift pumps were pretty much trouble-free.



Word on the street is that Jim Fulmer ran that very setup on his ISB with a pressure regulator (VP-44's don't like 25psi at idle and 35+psi going down the road) and it worked really well.



Matt

 

[Gary - K7GLD]

"I'm not sure if this is good news or bad news. If the pumps live, it will be fine. If they don't, we'll be dropping tanks on the side of the road to change transfer (lift) pumps. "



EXACTLY!



And as also mentioned, too bad the later engines don't also use the mechanical pump - but maybe the VP-44 meeded a more reliable system PSI right at first engine crank, and the small lag inherent in the mechanical pump was a factor?

 

[RJOL]

Don't like the idea of the FP in the tank. I'd rather have it accessable so it can be changed easily. My first one died at about 20K. Replaced under warranty, and although I would like a little more pressure, it still runs at 8-13lbs under all loads with over 50K on the clock. The FP gauge was one of my first mods. It lets me know exactly whats going on with fuel pressure, and if it starts acting up, I'll just replace it again...

 

[A Johnson]

I may be way off here, but, who buys a gasser rig and worries about the pump in the tank? Last three gas rigs I bought have a pump in the tank as far as I know. I don't worry about changing the pump on the side of the road, although we all know they go bad. It's just that they go bad at a very high mileage. Most people probably do not keep a gasser around for 200K plus miles like they do the diesels.



My point here is, if a gas engine has a pump in the tank producing 50 plus psi and it last an average 200,000 miles, why would we all of a sudden worry about a pump in a diesel tank pushing 15 PSI not lasting just as long or longer. Then we just come up with a 175K mile maintanence change out. Can't be any worse than doing some of the timing belts at recommended factory interval of what, 60-70K?



A Johnson

 

[Gary - K7GLD]

"I may be way off here, but, who buys a gasser rig and worries about the pump in the tank?



Well, Camaro owners sure "worried" about the pump in the tank - they tended to fail LOTS more often than OUR pumps do~



But yeah, *IF* we could count on ANY LP lasting 200,000 miles, that would be a big plus - anyone out there know *FOR SURE* of any that can deliver that mileage, absolutely no doubt about it?



... I didn't think so!

 

[RJOL]

... My point here is, if a gas engine has a pump in the tank producing 50 plus psi and it last an average 200,000 miles, why would we all of a sudden worry about a pump in a diesel tank pushing 15 PSI not lasting just as long or longer... A Johnson

Well... if you can guarantee 200K for my lift pump, maybe in the tank is alright. But, with the history of this pump failing, I want it where I can get to it without dropping the tank. I'd rather replace the pump twice before I'd like to drop the tank once. If the 2005's have cured the pump problem then so be it... but I think I'll wait to see what their experience is after a few 10's of thousands miles before I join the "cured" bandwagon...

 

[Joe G.]

*IF* we could count on ANY LP lasting 200,000 miles, that would be a big plus - anyone out there know *FOR SURE* of any that can deliver that mileage, absolutely no doubt about it?



... I didn't think so!

The lift pump on my '95 has over 233K on it. Idles at 25 PSI, runs at about 40 PSI.

 

[DieselMinded]

Well... if you can guarantee 200K for my lift pump, maybe in the tank is alright. But, with the history of this pump failing, I want it where I can get to it without dropping the tank.

If they put a pump in the tank it will not be a lift pump thats the whole problem ... . if its in the tank its a pusher pump its alot easier to keep constant pressure when pushing the fuel to the injector pump than it is LIFTING it all the way to the motor ... HINTS the 4 LIFT PUMPS changed before 40,000 miles I seen in another thread... . thats nuts there aint no way Id go threw that at first signs of the lift pump going south that babies comming out and there will be a push pump instead



the lift pump is a major design flaw IMO but the point A Johnson made about the motor having to be self suffent because of the broad span of applications makes alot of sence.



When they sell over 1 million cummins you'd think they atleast ship the motor to DC with no lift pump and let DC supply the pusher pump.



I wonder if TDI's have pusher pumps???



DM

 

[MChalkley]

If you mean VW TDI's, yes they do. The old VW diesels had lift pumps and the same "problems" that the lift pump scenario has (now "had", I guess) on the DC's. My '04 Passat TDI has a pusher pump, as did my '96, and I'm very grateful for the change. My '96 got 345k on it with no problems with the pump (or anything else engine-related, for that matter), and she sure was easier to start when you ran out of fuel. (Ax me how I know... )



My '93 DC ran out of fuel with 300 miles on it, because of a problem with the pickup in the tank. Had to be towed in, because nobody could get the blasted thing started on the side of the road. It took the dealership most of a day to get it going. I think a lot of that was because it was so new and tight, but they ended up having to replace the lift pump because all the manual pumping ruined it.



I've got a tractor/loader/backhoe with a Kubota engine in it that uses a lift pump. It ran out of fuel once because a ditch bank caved in and the machine lurched far enough to one side to create a brief disruption in the supply, and that was enough to kill it. If you've ever been on a machine just about to tip over and then you lose power on top of all your other problems, you know what panic feels like. So I'm hoping for all I'm worth the thing doesn't go on over before I can run a mile to get my DC and get a chain on it to stabilize it. That kind of excitement doesn't happen with pusher pumps. Guess what my next mod on that machine was?



No, thanks, I'll take pusher pumps any day of the week, no matter how hard it might be to replace them when they fail. So when I saw the '05 had a pusher pump, that was a big reason to jump on it, for me, at least.

 

[RJOL]

... at first signs of the lift pump going south that babies comming out and there will be a push pump instead...

Will you be putting that new pump in the tank??? Merry Christmas...

 

[DieselMinded]

lol



I thought about a coustom jobby----A push pump then a lift pump about 12" down the fuel line and repeate about 10 times all the way to the injector pump NOW thats a set up.



LOL

Merry christmas

DM



thanks for the TDI info

 

[Idaho Native]

Because

if the lift pump hadn't failed on my '99, then I would not have a single thing to gripe about in the six years I owned the thing



Hope my 05 has the same good luck!

 

[mhenon]

I don't believe the newer VW TDI's have a push/lift pump. The injector pump (Bosch VP 37 distributor-type pump) does all the work of supplying fuel. You don't hear of many problems with this system unless something plugs up the fuel tank module (like ice or dirt). The advice on Fred's TDI is to pull the fuel module and drill out the supply line restriction..... no more problems.

I just wonder how many of us have a plugged up fuel tank sender and don't know?

Mike

 

[RustyJC]

I may be way off here, but, who buys a gasser rig and worries about the pump in the tank? Last three gas rigs I bought have a pump in the tank as far as I know.

My wife's Durango SLT+ with the 5. 9L left her stranded in the middle of an intersection here in Houston. Bad fuel pump (in tank design) at 32,000 miles. It happens... .



Rusty

 

[A Johnson]

Yes it does happen, and I'm sure it happens on all makes of vehicles.



My point here is that if they had an in tank design from the get go , the transfer pump would not be the number one topic posted in the 24 valve forum. I get the feeling a lot of people feel an in tank design would be have the same reliability of the current set up, and I don't believe it. Unfortunately Cummins and DC have moved on to newer fuel system designs and any research by them on VP-44 or lift pump reliability is simply damage control, for the least amount of dollars, at this point.



A Johnson

 

[DieselMinded]

my Lp is on its way out



How convenient



DM



looking in to my options ,fass,rasp,just the pump,electronic pusher, what ever I do I will not replace the Lp with another Lp it just dont make sence to me yes its cheaper @ first but in the long run the pusher pump will catch up.