6.5 TD Lift Pump

[QinVB]

I read recently that the lift pump for the 1993 GM diesels had higher pressures and was the LP that should be used. It supposedly has higher pressures - both static and after engine is started and makes life easier for the IP.

The LP on my '98 is sounding tired when I turn it on first thing. Takes a while to pump up. I'd like to put the Walbro on, but $'s a little tight right now, and the Rock has a brand name '93 for <$40.00!

Any opinion?

 

[NVW]

The 93 LP is better than the other stock ones, the Walbro is better when finances allow.

 

[QinVB]

The Airtex(identical to the AC Delco for 20 less)pump for the '93 PSI is listed at 9.5 min. 14 max. The '98 is listed at 6 and 8 psi. If more is better I'm in.

Just want to make sure it's a good thing.

 

[Will L.]

IGNORE ANY SOUND FROM ELECTRIC FUEL PUMPS. In the fleets I have heard crazy sounds from pumps that worked great for a long time. I have had pumps that sound normal and do nothing.

TEST TEST TEST- NOTHING ELSE MATTERS!
Most all autoparts stores have tool loaner programs if you cant currently buy a pressure gauge to test with. If you have a boost gauge- it does the same thing, use it for the test. You might have debris blocking a line and a great pump in there.
I have replaced my own old fuel pump just because it had 10 years on it. Tested first for reference- then installed a new pump- guess what- old pump had more volume and pressure than the new one.

The best of the factory style lift pumps is the AC Delco ep158. The problem with using brand X pump is they all look the same and will all work. Anyone can list a pump working for a 93, even if it is a poor perfoming one because when you put it in it will fit and work.


Rock Auto is a vendor, here is a snapshot of '93 list today. What would I buy- the ep158 for $58.79. If everyone is as good as the ep158 then the cheapest one would be ok. Give me the first 7 for free and I would put them in my truck-only use them to throw at whoever cuts me off. But as far as pumping my fuel? No. If I am broke at the time- I would use a junkyard one because its way cheaper and installed in 4 hours. Ok if I am broke and someone gives me 1 free I would run it. But no way would I buy one if not in a serious bind.

Your Options IMO are:
stick with what you have until you can afford a walbro frc10 if it is working.

Spend the extra $20 and know you are getting a pump worth buying and get the ep158.

 

[QinVB]

IGNORE ANY SOUND FROM ELECTRIC FUEL PUMPS. In the fleets I have heard crazy sounds from pumps that worked great for a long time. I have had pumps that sound normal and do nothing.

TEST TEST TEST- NOTHING ELSE MATTERS!
Most all autoparts stores have tool loaner programs if you cant currently buy a pressure gauge to test with. If you have a boost gauge- it does the same thing, use it for the test. You might have debris blocking a line and a great pump in there.
I have replaced my own old fuel pump just because it had 10 years on it. Tested first for reference- then installed a new pump- guess what- old pump had more volume and pressure than the new one.

The best of the factory style lift pumps is the AC Delco ep158. The problem with using brand X pump is they all look the same and will all work. Anyone can list a pump working for a 93, even if it is a poor perfoming one because when you put it in it will fit and work.
View attachment 48493

Rock Auto is a vendor, here is a snapshot of '93 list today. What would I buy- the ep158 for $58.79. If everyone is as good as the ep158 then the cheapest one would be ok. Give me the first 7 for free and I would put them in my truck-only use them to throw at whoever cuts me off. But as far as pumping my fuel? No. If I am broke at the time- I would use a junkyard one because its way cheaper and installed in 4 hours. Ok if I am broke and someone gives me 1 free I would run it. But no way would I buy one if not in a serious bind.

Your Options IMO are:
stick with what you have until you can afford a walbro frc10 if it is working.

Spend the extra $20 and know you are getting a pump worth buying and get the ep158.

Will, when you pull up the pictures of the Airtex and the AC Delco it is the exact same picture with the same part number on it!?
I will be pulling an equipment trailer with this truck and making 5 hour trips to NJ(no trailer) in it. I don't want that LP to crap out in either of those two situations. My truck is a utility bed, and I will have all my tools and a jack in it. Even if I only keep the pump in one of the compartments as an emergency spare, I am going to get one. The Walbro is $150.00 with shipping! I need other things more than that pump. Do you think it's possible Rock Auto put the same picture for both pumps by mistake??? I don't mind the $20, but if it is the same thing - why pay more?

 

[Twisted Steel Performance]

It's just a picture, not the actual part for most of the time... if any doubt stop by the dealer and pick one up...

 

[Twisted Steel Performance]

Best thing would be 20$ & some time and install a psi gauge between the filter & IP and their won't be any doubt if you have pressure....

 

[QinVB]

I evidently have pressure, the truck is running. As I stated above, it is the sudden stoppage caused by a tired LP that craps out that I want to avoid. Replacing it is the same to me as installing new oil cooler lines to avoid a blown engine, or a new oil pressure switch, PMD relocation, vacuum pump delete with manual WGA, etc, etc. My aim is to avoid a breakdown when I'm pulling 5 tons, or am 200 miles from home. My question was whether or not it is better to install the 1993 LP which has higher PSI or not. It's $50.00 for crying out loud. The cheapest thing I have done to the truck to avoid unanticipated problems.
I'm sorry I asked.

 

[Quadstar Tuning LLC]

My honest experience is that I wasted way too much money on stock style lift pumps over the years. Should have switched to the FASS sooner. I run a DRP02 with a 9psi spring. Have three ep158s on the shelf that all went to shit after a few thousand miles.

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[QinVB]

My honest experience is that I wasted way too much money on stock style lift pumps over the years. Should have switched to the FASS sooner. I run a DRP02 with a 9psi spring. Have three ep158s on the shelf that all went to shit after a few thousand miles.

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Thanks Quadstar87. It's listed for Cummins and is $100.00 more then the Walbro, but users talk about having it last 500k miles or more. I assume you just plumbed it to work on your '94. An special reason you have it limited at 9 psi?

 

[QinVB]

Still like to know if running a 14 psi LP is okay to do on an engine that only gets 8 psi max with the stock LP from the factory.

 

[Will L.]

Airtex makes total P.O.S. pumps. Looking the same and a similar number means jack squat!

Your lift pump can make noise like it is new, be totally dead, and the engine will run. It beats the living crud out of the IP.

Stock ds4 should run at 9 psi. Not 14. Quadsteer did it right by regulating it.

If you have a working factoy lp, dont spend money until you can afford a quality pump.

 

[QinVB]

They don't look the same and have similar numbers. It is the same picture of the exact same pump with the exact same number on both of them. So how much squat is that???

 

[Twisted Steel Performance]

OK, good luck.........

 

[Quadstar Tuning LLC]

Still like to know if running a 14 psi LP is okay to do on an engine that only gets 8 psi max with the stock LP from the factory.

Because we've accumulated enough miles to re write the requirements and redact the incorrect information over time. The DS4 pump responds well to the 9-12 PSI range and the longevity of the IP depends greatly on maintaining the fuel supply volume. The FASS pump was built for the dodge VP44 IP which has very similar supply requirements to the DS4 as far as maintaining pressure.

I'm not as frequent on this forum as others but I feel this information is not misleading. I skipped the Walbro due to longevity concerns and being tired of laying under my truck messing with pumps when my gauge hit 0psi.

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[Quadstar Tuning LLC]

FASS did change the pressure spring In the DRP pump somewhere in mfg to 18psi. It can easily be swapped to a lower spring since that's how they originally sold them. Some people run more pressure than me but I haven't needed to. The Raptor pump looks good too but these don't need 1/2" lines or 100 GPH. I mention a specific brand because it has solved my problems but the concept is what's more important to grasp.

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[Will L.]

Wasn't trying to be a jerk to you. Sorry if it came across that way. My anger is at them trying to rip people off with misleading practices. The difference in the part number is subtle.
EP158
E3158
P vs 3
Notice they even do a label that looks similar to the AC Delco.

Airtex makes horrible copies of whatever the best quality part is, and copies the part number as close to possible to confuse customers tying to buy the real deal. Don't fall for it. Looks like they had you on the line with the marketing trick- be glad you asked hopefully you havent ordered it yet.

Nothing should be wrong with the idea of replacing a tired old part in theory, but new part failure is becoming a much more common problem. Also when it comes to this design of pump, sometimes people get months out of them, others way over a decade.

Best example ive seen yet just occured: An old coworker bought from a fleet we worked at it got a gauge installed when brand new- a 99 2500 with just over 350,000 on it- factory pump went out this year. I hadn't spoken to him in years, he called me up just to tell me that and aske if I wanted to frame it, and to eat some friendly crow- I made the call to install a gauge in each truck and that became part of his job. He said "ok, now it's finally justiied."

That's why addition of a dash mounted gauge is so worth it. Just a random swap by mileage would have spent extra $. How often, every 50k? 100k?

Thats why I was saying test so vehemently. I don't have extra $ to waste, and by you looking for a good deal I figured you don't also. Replacing the LP that might be bad now, or might be good for another year just because is not how to save $ IMO. The new pump could fail you by December, and without a gauge you could wipe out your IP by summer. Usually a truck learching under acceleration (fish bite as someone here coined) occurs first, but not always.

Really not trying to be a jerk- hope I can help you.

 

[Quadstar Tuning LLC]

Good advice on the gauge. Really the only way to know what's happening. It's common to see pressure at idle but suck it to 0 under load and lead to the demise of your IP. The #1 gauge to add IMO to any 6.5. Boost and EGT next if you start modifying things.

The transfer pump inside the IP multiplies the incoming pressure to fill the plungers and fuel is the lubrication so keep it coming!

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[QinVB]

I appreciate your responses quadstar87. This is more of what I was hoping to get back, as opposed to angry sounding opinions about this brand or that brand.
I've read that the DS4 , and the engine as a whole operating system, likes more pressure than the stock pumps make when they get old and don't make enough psi - most importantly under load. I think it's safe to say that it is common knowledge that low pressure from the LP is very bad for the DS4. It appears to me, with all I've read and watched on YT, when they get old, and mine looks and sounds very old and weak, makes acceptable psi at idle, but I can't measure it under load. (Although many expensive items have been repaired, like $400.00 PMD replacement, on this truck, the more minor maintenance items seem to have been ignored by keeping quarts of tranny fluid in it instead of fixing the leak I just took care of and the leaks in the power steering system. I spent 20 years working for two local cities and they all do oil, filter and lube every 3,000 miles, and "If it ain't broke, leave it alone" with no preventative maintenance is the order of the day.
All I'm hearing here is that OE LP's are P'sOS that never last long. I've seen demos where an OE LP makes acceptable psi at idle, but under load the psi drops down to around 4 psi so checking the pressure in the driveway is rather useless, and that is the only option I have with my FI pressure tester. On the other hand I just read yesterday that too much pressure is just as bad, as it can overheat the IP, blow the front seal, and make the engine go into limp mode if the truck hasn't been reprogrammed - with a surprising number of examples of that described in forums, and one poor guy paying hundreds at several dealerships for work that never solved the problem. So I understand why 9 psi, a steady no load/heavy demand 9 psi that is constant, is good. I GET IT WILL L., I wanted to hear it in a more calm manner from quadstar87, thank you very much anyway.
I bought this old truck, because my business failed, due to the market demand for my work, not the way I did my work, or ran the business. I had to sell my reliable 3 yo truck and bought this truck, because it was what I could afford. My only goal at this time, and as I can afford to, is to make it reliable and address all the things that give the 6.5 TD a bad rap - you know the "Make your 6.5 TD Bullet Proof" that is all over the inet. The LP is the most controversial of all the 'bullet proofing" subjects with some people putting prefilters on the stock units and never having a problem, and others just bashing the hell out of any stock Delphi, Carter, ACDelco, Airtex or whatever. I was hoping to get feedback from informed members that had actually experienced a successful solution, rather than a decision made out of something more than just anger and frustration. I have to say I'm very disappointed in the kind of response I got. But, I appreciate your input - thanks.
I've made my decision, good or bad/right or wrong: I'm going with putting the '93 9 to 14 PSI with a prefilter on the truck. I used bulk fuel in my last truck and it got filtered 3 times before it went through the Cummins and I never had a problem- not a hiccup. I have too many other, more expensive things to do to make this truck reliable for my needs, and to complete the 'bullet proofing'. I already have an extra filter base I bought and didn't get around to using so this will cost me $50 bucks that I can afford at this time. I have several things I need to buy from Leroy Diesel that are more expensive but will prevent very expensive failures. If I get a decent job - it's been a while - I will go with the FASS, It's not just a better substitute option to OE, it's a permanent solution.

I will post again to let others, who have the same curiosity I had, know how things go with my set up. Otherwise I won't be posting any new questions on here anymore. Yeh, I know Will, I can hear you saying, "Good riddance".

 

[Will L.]

No man, I'm really not. And seriously didn't intend to offend you. One of the things I really like about this forum is a lack of trash talkers- and I never want to be a part of that attitude. I appologize for coming across like that. I should have approached my entire response differently. When you sent me the pm about this thread asking for my response, I figured you knew I was loud and outspoken guy. I didn't think for a moment to carefully word my thoughts. I should have said something to this effect:

I ran a couple of huge fleets that had large numbers of 6.5s - many that turned over 200,000 miles in just a couple years. One of the fleets was for an oil/gas company that did testing for vehicle mfrs. In the shops we replaced fuel pumps into the hundreds. I am not a fan of this style inline pump, but of all the brands we tried, the AC Delco was the best. Of the AC Delco the EP158 is the best. Then if I had been smart enough to ask which pump exactly you were looking at and learned you were considering the airtex- I would pointed out that airtex attempted to mimic the EP158 to the point they use an almos identical part number only changing one letter of the original part number. I still continue to test other options as $ and time permits such as this one that failed as horrible as the airtex, (I wouldn't be surprised if thats all it is):

This one is sold by a company supposed to be making upgraded Hummer parts.


The most important move you could make at this point is installing a pressure gauge to monitor the pressure. When the LP does fail, replace it with the best one you can afford, with an EP 158 being a minumum acceptable pump.

Sorry I handled my responses to you so poorly.