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Bellrule
01-30-2004, 15:24
I installed a post-OEM mega a couple of weeks ago and have been toying with the idea of putting on a lift pump. My truck died on me this morning (about 10 degrees out). I had put about 3 times the regular rate of Total Power in when I filled the night before, so it should have been treated well enough. So it made me think that possibly the vacuum stock system was having a tough time pulling the "cold" fuel thru both filters. Anyway it has got me thinking more about a lift pump again and I was wondering how people who have had them installed for awhile are getting along. By the way, I took the OEM filter off and had ice in the bottom of it. I will be putting a new filter on and try to get it going tommorrow when it is supposed to be 50 out!

a bear
01-30-2004, 15:58
I have somewhere in the neighborhood of 35,000 troublefree miles on my pump so far. ;)

LanduytG
01-30-2004, 16:15
a bear
If youwould please email me your phone number, I have lost it somewhere.

Greg

Kennedy
01-30-2004, 17:29
Waiting for revised harness design to be prototyped. First design was quite close, but adding some details...

Flyboy
01-30-2004, 17:56
I have over 6,000 on my Racor-lift pump-Cat setup with no trouble. I am not running any pressure regulation either.

jbplock
01-31-2004, 04:46
Bellrule,
I've also got 14k trouble free miles on my setup (http://community.webshots.com/album/77018086bLHHHC) with no regrets... All the filters are fully packed with fuel, the engine runs smoother & more responsive... and the LP makes bleeding new filters a breeze.

I was also talking to John the other day and what he is cooking up sounds pretty good ... give him a call.
smile.gif

YZF1R
01-31-2004, 05:42
Bellrule, I think you hit the nail on the head. I had no problems untill the freezing temps. On start up, that pocket of air is stretched trying to start pulling fuel and "gulp", a slug of air with the resulting stumble/stall. Currently, I am bleeding every evening when I get home so I have no problems in the morning.

I have also been in contact with John and I'm awaiting what I am sure will be an excellent product.

Steve

Kennedy
01-31-2004, 06:19
I've also got a test underway to try and help the air to pass w/o a lift pump. I'm sure we ALL have air in the system, it's just that some are less tolerant.

One thing I do is lube my orings on the filter/seperator, AND both sides of the Mega. I hold the seals in hand and smear with dielectric grease.

Bellrule
01-31-2004, 16:25
One thing I found out with a '90 Dodge Cummins, is that the truck had a bad lift pump and though it would start and run it would start with more trouble espescially in cold weather. Since I figured out the problem and put on a new lift pump it is starting great and has been no problem in cold weather. That brings me to the next area. It seems that the way most of you are hooking up the lift pump is through an oil pressure sending unit. I think that it would help the truck to start easier if the pump came on with the key , thus had fuel pressured to the injection pump right away. I inderstand the safety reasoning but the gas vehicles I have seen with electric pumps outside of the tank come on wtih the key.

jbplock
02-01-2004, 03:24
Originally posted by Bellrule:
One thing I found out with a '90 Dodge Cummins, is that the truck had a bad lift pump and though it would start and run it would start with more trouble ...

... most of you are hooking up the lift pump.. through an oil pressure sending unit. I think that it would help the truck to start easier if the pump came on with the key , thus had fuel pressured to the injection pump right away... Bellrule,
You make some excellent points. http://forum.thedieselpage.com/ubb/icons/icon14.gif The GM 6.5s also have a lift pump (the same pump some of us are using on the Dmax). When the LP fails on the 6.5 the engine will run but it can cause stalling/starting problems. When the LP failed on my 98 6.5 I didn’t find it until I tried to bleed a new filter using the pump. Prior to that I had an occasional stall. The nice thing about the AC Delco pump (EP158 or EP309) is that they are a flow through design. If I pull the fuse on my Dmax setup, the truck starts and runs fine – just may get some out-gassing in the fuel.

Also, having the pump on instantly at start-up is an excellent feature for the reasons you stated. (In talking to John about his new harness I think be agrees). IIRC, on the 6.5’s the ECM overrides the OPS and powers up the pump as soon as the ignition key is ON. Once the engine is running, the OPS takes over and controls power to the Lift Pump (for safety). I looked into adding this feature when planning my setup. I found a one-shot timing board that would have worked but decided against it due to the added expense. It would also be fairly easy to make a one-shot timing circuit to accomplish this using a 555 timer IC (or similar circuit). Another way is to wire a momentary switch to the pump relay and place it in the cab. Just push the button for a few seconds before cranking and this will slightly pressurize the fuel lines. I bought the switch but haven’t put it in yet. However, I think JK’s new harness will be the ticket.
smile.gif

Kennedy
02-01-2004, 06:32
All that AND a manual puhbutton activator (under hood where you need it) for bleeding filters at service time!

It's been a long, drawn out affair with my electronic guy designing the digital circuit etc...

[ 02-01-2004, 05:50 AM: Message edited by: kennedy ]

Bellrule
02-01-2004, 09:00
I'll be looking forward to that as I spent an hour and a half trying to get my fliters bled after changing them out yesterday!!! Maybe it is just me but it seems like the manual primer pumps are very poor.

JEBar
02-01-2004, 09:14
John ....

Thanks for the info on your lift pump ... looking forward to installing one

Jim

deerhunter7
02-01-2004, 10:54
I have had my Pre Racor now for about 8000 miles and never have had any problems. Was down to 24 below last week and run fine. To loose your prime I would think you have to be sucking air from one off the connections. From my own exprience I don't need a lift pump. With a larger filter there should be less resistance in the filter. I say back to basics find air leak.

chuntag95
02-01-2004, 11:58
I've got 8K on my lift pump and 3 filters with no problems. I still have a sight glass on top of my Mega that will catch air if any shows up. It hasn't since the install. I have a switch for priming under the hood and it was nice on the last filter change. a bear, jpblock and I built ours all around the same time using most of the same components and ideas. JK was a constant source of info and help throughout. His system will probably take less time and be "cleaner" of an install than you could do on your own. He knows what problems and stuff we went through in addition to his own testing. I'd recommend going with his unit as opposed to building your own, unless you just enjoy that kind of stuff like me. I'd say JK's might work better than mine, but unless he's putting a digital pressure gauge on it that can be read from the cab, and an automatic pressure adjustment system, I can't see how. tongue.gif Plus, mine has that really nice protective box that I made with rivits, sheetmetal, a hammer and undercoating. Boy is it ugly! But, it works and blends in nicely with the frame. To make a long story short, I'm glad I did it.

More Power
02-01-2004, 13:17
These trucks come prewired for an electric fuel pump that is controlled by the ECM and "fuel pump relay".

JK thinks this may be for the dual tank transfer pump, and he may be right, but it would be nice to use existing truck circuitry with ECM control.

My 2001 GMC 2500HD has the components (less pump), as does the harnesses/fuse/relay panels I bought for the Duramax project truck.

The wiring diagrams show the circuit, and there is a pictorial of a "lift pump" inside the left frame rail in the illustrated "diesel" portion of the 2001 wiring diagram book.

Not sure what it all means yet.....

MP

Kennedy
02-01-2004, 15:09
Someone once said it was for an aux tank, but GM only used one gauge, so the pump would transfer fuel to the main tank.

Dunno from there...

Idle_Chatter
02-01-2004, 17:17
I've seen that same illustration in my 2001 manuals - I'm certain that it's the transfer pump for the chassis-cab variants. Pumps fuel from the aux to the main tank.

Bellrule
02-01-2004, 17:57
Yes, it was told to me that it's a pump to keep the two tanks even on a cab and chassis like mine. I don't know what triggers it to pump. The book says to fill the front tank unless you are going to fill both.

a bear
02-01-2004, 20:22
More Power said

These trucks come prewired for an electric fuel pump that is controlled by the ECM and "fuel pump relay".

JK thinks this may be for the dual tank transfer pump, and he may be right, but it would be nice to use existing truck circuitry with ECM control.

My 2001 GMC 2500HD has the components (less pump), as does the harnesses/fuse/relay panels I bought for the Duramax project truck.

The wiring diagrams show the circuit, and there is a pictorial of a "lift pump" inside the left frame rail in the illustrated "diesel" portion of the 2001 wiring diagram book.

Not sure what it all means yet.....

MP
Does anyone know the physical location of the wiring for this ? Transfer flow states that their aux fuel tank pump kicks on @ 1/4 tank on the OEM gauge to fill and off @ 3/4 tank to shut the pump off (All automatically). I would think this is where they are wiring in.

a bear
02-02-2004, 16:30
Posted by Chuntag95

I'd say JK's might work better than mine, but unless he's putting a digital pressure gauge on it that can be read from the cab, and an automatic pressure adjustment system, I can't see how. OK Chris, Why did you have to get those wheels turning in my head again. Is this classified information or are you going to leak a little information like what you installed and at what cost. I keep picturing that nice looking digital gauge mounted in my cab. :D

chuntag95
02-02-2004, 18:23
I was just saying what I wish I had. I've been building bunk beds, not control units. It is a free suggestion to JK's electronics guy. ;)

a bear
02-02-2004, 19:01
The best price I could find on a pressure transmitter and gauge for vac/press service was over $300. :( Didn't really do a lot of searching though. If someone can put together a kit it would benefit even those who are not running a lift pump. Would be a good tool to monitor filter restriction.

chuntag95
02-03-2004, 07:31
I hear you on the transducer prices. I think I found one in the same range and decided to skip it ..... for now. Besides, I just got finished catching up on the coolant filter and need to get started on one of those. :rolleyes:

Kennedy
02-03-2004, 10:17
IMHO, a liquid filled mechanical gauge used at regular intervals in controlled conditions is the best choice. There is such a dynamic swing in psi when running on the road.

I have my second SPA hooked up to the test port, and as soon as you start to move, the psi shifts.

I'll also pretty much guarrantee that unless you have a VERY stout delivery pump, the psi at the test port will fall sharply under accelleration.

I've had some thoughts on the coolant filter thing, but haven't yet acted as time is short as of late.

a bear
02-03-2004, 16:31
IMHO, a liquid filled mechanical gauge used at regular intervals in controlled conditions is the best choice. There is such a dynamic swing in psi when running on the road.

I have my second SPA hooked up to the test port, and as soon as you start to move, the psi shifts.

I'll also pretty much guarrantee that unless you have a VERY stout delivery pump, the psi at the test port will fall sharply under accelleration.

I've had some thoughts on the coolant filter thing, but haven't yet acted as time is short as of late.

When you stop and think about it this is probably true. Even with a in cab gauge you can only check the pressure for comparing numbers at a controlled time. The in cab gauge would be nice but I guess the benefit to cost ratio would keep me from biting that $300 bullet.

chuntag95
02-03-2004, 18:51
JK, I said "wish". You know the old saying "If wishes were horses, then beggers would ride." Accuracy is just like $peed, it just costs for more. :D

Modified
02-23-2004, 22:12
I (finally)installed a Lift Pump, the Product Engineering PE4100, ( www.productengr.com (http://www.productengr.com) ) . This pump is rated for 270 GPH free-flow and 11-14 PSI, and it is rebuildable with a kit.
John @ Prod Eng recommended mounting this pump under the hood. He stated this pump wasn

Kennedy
02-24-2004, 05:49
I'd like to add that my current lift pump project is NOT a high performance device, rather a simple pump to keep the fuel supply under pressure during normal operation. It is quiet, and will allow easy pull through in the event that it stalls.


In talking to various individuals who have been running lift pumps, I have found a common thread that is also consistent with the aux filter addition:

The Duramax just plain seems to run better, smoother, more responsive, and starts better. Now I'm still not saying that we NEED a lift pump, but it seems that the air in fuel may be causing a distinct effect.

I should add that a couple of the parties that have claimed improved running noticed distinct changes in operation when the pump became accidentally deactivated...

Viking
02-24-2004, 17:13
Does anyone know of,or seen, any downside to pressurizing the vacuum side of the Bosch pump? Could there be a potential problem with seals leaking in the Bosch?

jbplock
02-26-2004, 03:33
Originally posted by Viking:
Does anyone know of,or seen, any downside to pressurizing the vacuum side of the Bosch pump? Could there be a potential problem with seals leaking in the Bosch? Viking,

This is a good question and it was a topic of discussion in the early lift pump/air-in-fuel threads (search on "air in fuel" or "lift pump" for more info). IIRC the consensus was that pressures less than 6-7 psi were not a problem. Not sure how high it could go although in the above post by modified, he is running a bit higher. Some folks (myself included) are using an AC Delco EP158 lift pump (http://community.webshots.com/album/77018086bLHHHC) (or Stanadyne FM100 lift pump) with a bypass regulator that limits the pressure into the OEM pump. I have mine set for 0-1psi at idle as measured at the Schrader valve test port. Others are running the AC EP309 (similar to the EP158) or Stanadyne FM100 lift pump without the regulator. So far I do not recall anyone posting reports of pressure problems with these setups. I added the pump to prevent vacuum induced vapor build up in my Mega Filter but it also yields a noticeable improvement in the how the engine runs. I recently discovered my lift pump fuse had come loose and caused the pump to stop working. When I tightened the connection and the pump started working again I noticed a significant change in how the engine ran.. It was smoother, quieter and more responsive. For a few weeks prior to this there had been a little more "diesel noise" and a feeling of less power which I had attributed it to winter fuel. However, after finding the loose lift pump fuse, I realized it was not the fuel after all but rather the Lift Pump had stopped.

smile.gif

GM Smitty
02-26-2004, 04:53
Bill - I'm not sure if you like the idea, but I installed a small LED from Radioshack that let's me know the lift pump is getting power. I guess the pump could still stop working, even though it is getting 12V, but at least I know the O.P. switch/relay/wiring is working OK up to that point. I still take a listen every once in awhile to make sure it's running.

And to echo previous comments, my truck has been trouble free and running great with the addition of the lift pump last July. Filters also look very uniformily used when replaced. I'm runing a similar set-up to Bill with the bypass, and the pressure set at about 1psi at idle. No air buildup whatsoever.

Josh

jbplock
02-26-2004, 10:00
Originally posted by GM Smitty:
... I installed a small LED from Radioshack that let's me know the lift pump is getting power.... Josh Josh,
Great idea! http://forum.thedieselpage.com/ubb/icons/icon14.gifWhere did you mount the LED?
I check my vac/pressure gauge (http://community.webshots.com/photo/77018086/78007628dTiRDx) (on top the mega bleeder port) every once in a while when the engine is running to make sure the LP is running but having an in-cab indicator would be nice. Another thought I had was to plumb a pressure and/or a vacuum switch to control a cab mounted indicator light but your idea is more practical. I also have a momentary push button I plan to wire up to the pump relay and mount inside the cab. The pump can easily be heard when the truck isn't running plus it seems like the engine starts a little quicker when the fuel line is primed. However, as previously discussed the ultimate setup would be an in-cab fuel vac/pressure gauge.

smile.gif

GM Smitty
02-26-2004, 15:21
Bill, I have mine mounted on the small shelf below the door that flips up for access to the lighter/power points. You can see it here (http://pic5.picturetrail.com/VOL72/839020/2599589/31662100.jpg)
The middle rocker is a manual switch for the lift pump, and the right rocker for the high idle.

It's nice because the LED is not staring at me all the time, but it's easy to check also.

Josh

jbplock
02-27-2004, 03:00
Josh,
Nice job!! http://forum.thedieselpage.com/ubb/icons/icon14.gif. Your switches and LED have the "OEM Look"... I think I may follow your lead. I was planning on mounting my switches out of sight on the lower lip of the dash (below the steering wheel) but I like your method better. :cool: Thanks!

I also checked out your Stanadyne Lift Pump Install Pics (http://www.picturetrail.com/gallery/view?p=999&gid=2599589&uid=839020). Also very nice! http://forum.thedieselpage.com/ubb/icons/icon14.gif I noticed your 30 micron filter is a (black) 34878 reverse flow model. (http://www.reliableindustries.com/inv/stan/elementinfo.php?search_for=34878) I have a (red) 31865 (http://www.reliableindustries.com/inv/stan/elementinfo.php?search_for=31865). Just curious ... Does the FM100 lift pump require the reverse flow element or is there another reason to use it? I also just ordered a bowl kit like yours for my setup. (http://community.webshots.com/album/77018086bLHHHC) Do you ever see any water in yours? When I called Stanadyne to ask about the bowl kit they mentioned they have a 10 micron element coming as well as a Duramax kit similar to the RACOR. Sounds like the Dmax kit will be an FM100 with a 10 micron element and a bracket for a frame rail mount. I may switch to the 10 micron element when (if) it's available but I would also have to add the the heater option.

smile.gif

[ 02-27-2004, 02:58 AM: Message edited by: jbplock ]

GM Smitty
02-27-2004, 04:33
Thanks for the comments Bill! Let me say that I learned alot about my lift pump set-up from watching you build yours. I couldn't have done it myself without some guidance. :cool:

Yes, the FM100 lift pump requires a reverse flow element. There are quite a few choices in height and micron rating (5/30/150). I opted for the shortest filter so it wouldn't extend past the bottom frame rail and the 30 micron element.

I've never seen water in the bowl, but I do use FPPF every tank, so that may be why. I also haven't looked for at least a month, but I 'd be surprised if there was any in there.

I'd really like to get a fuel vacuum/pressure gauge. Your setup is nice! I'm waiting for JK to get his finished. I haven't checked with him in awhile though, I see he has his hands full with some other issues (dyno). smile.gif

Josh