Fuel pump help

[stezloco]

I kindof agree with both of you regarding the sock thing...its needed but just not there in the tank...its hard to get at it in my pickup so I'm doing away with the sock in the tank when i get to it and fitting an agglomerator (or crap trap) with a big plastic see thro'bowl and drain so i can see the crud thats collecting (racer55 )....theres a fine mesh filter in the top of the agglomerator, i figure if its small enough to get past the mesh filter, then the pump can send it on to the main filter (phantom 309..NOW THATS A FILTER ! !)
Anyway it sends the problem further up the line but at least i would only have to get on my back to see the trap bowl and act accordingly from there. the sock over complicates the system it can be moved 'down the line 'so to speak where its easier to deal with.
isnt it a massive relief tho' you didnt go for changing the F.I.P??

[waynep]

I agree with D Max. Talking to various locals about this problem brought up the issue of where I typically get my fuel, and then all the rumors come out about the fact that this station is known for water in diesel etc. Makes me wonder.

I was not overjoyed when the mechanic told me that the sock is gone, but is was all back together and the thought of pulling the tank was not what I was looking forward to doing this weekend.

I will try and find an in line filter, seperator, before the lift pump to replicate as much as possible the in tank filter.

Also will try another local station for diesel fuel, but I bet they get it from the same distributor.....

At least it is running better and smoother than it has in years.

Regards,
Wayne

[DmaxMaverick]

That's pretty complicated. A lot more complicated and costly than the original design. In the end, may be less effective. The sock does more than just "filter" crud. It enlarges the uptake square area. If you have only a pipe, it won't take much debris to stop it up. Fuel tank obstruction happens, especially during winter. If your fuel begins to cloud, a little wax will plug the line. The sock prevents this temporary condition, most of the time. A marble or pebble will do the same thing. Fuel tank sender units are accessible by several means. If you need to access it, then something went wrong, and you should be in there. If your "other" filter system shows you some contamination, then you have to get to it, anyway. If a condition presents itself that would plug the sock, your high-dollar system will plug that much sooner. You don't control your fuel quality. You accommodate it. When you get a bad tank, a finer filter will stop the flow much sooner. When this happens, a course strainer in the tank is the best defense. The fuel manager will protect the downstream fuel system. They are also more restrictive, which may shorten lift pump life.

Be very careful when you try to out-think the engineers. The OEM design (of all vehicle brands, which are very similar), for the most part, has been extremely reliable and effective for nearly a century.

I'll repeat. If your sock has problems, the sock isn't the problem. Address the cause.

[JohnC]

Yeah, to rephrase, it takes hundreds of moderate size particles to clog up the sock, but only one to clog the pickup tube...

[Hooptybass]

Here is a few pics of the setup i have on my 94 K2500 burb

http://i288.photobucket.com/albums/l...s/DSC_0014.jpg

http://i288.photobucket.com/albums/l...s/DSC_0017.jpg

http://i288.photobucket.com/albums/l...s/DSC_0016.jpg

http://i288.photobucket.com/albums/l...s/DSC_0018.jpg

Hope i did this right .....hehe

[arveetek]

I got the IP replaced on the Tahoe, and now she is running again. However, I'm still having fuel supply issues.

I now have a Racor filter setup with a fuel pressure gauge installed. I was able to watch as the fuel pressure slowly dropped to zero after running for about 30 minutes. I took the suction side of the pump loose and put a hose on it and dropped it into a bucket of fuel. It wouldn't pull any fuel. I then put my finger on the end of the suction hose, and I didn't feel any suction at all. Next, I disconnected the outlet side of the pump, just to make sure there was no restriction. I ran the pump again, and absolutely no suction at all!!

Apparently, these Airtex pumps I've been getting are pure junk!!

Any recommendations on replacement lift pumps? I know AC Delco, Kennedy's Duramax pump, and the Walbro pumps are all options. Any other suggestions?

I might as well put the best in after doing all this work!!

Casey

[Burning Oil]

Did you prime the pump while doing your testing?

Here is another LP option. A Raptor 100.
http://www.pmdcable.com/index.php?ma...products_id=43

[DmaxMaverick]

Put this monster behind you. How much $$ have you "saved" by going outside the tried and true? AC Delco, or the Kennedy Pump(s). Just do it and be done with it. Or, keep this thread going for really long time.

If the pump is good and operating normally, it should NEVER need "priming". The pump should self-prime, every time. If it requires priming, either you have the wrong pump, or it's bad.

[Kennedy]

When evaluating pump options I suggest you do a web search on the name, add the word pump and then variable keywords like quit, leak, issue, fail, loud, noise, rough and I think you'll be surprised what you find (or don't) for some suggested here.

[arveetek]

Put this monster behind you. How much $$ have you "saved" by going outside the tried and true? AC Delco, or the Kennedy Pump(s). Just do it and be done with it. Or, keep this thread going for really long time.

I wasn't necessarily trying to save anything. I did the "tried and true" thing when I first bought the Tahoe. I installed an AC Delco pump that I bought from Kennedy. It lasted 35K miles. I then bought an Air Tex unit since I was in a hurry. It lasted 45K miles. I saw no need to go back to the "tried and true" since it didn't last as long as the second replacement unit.

Apparently I was just lucky with the first Air Tex pump. I have learned the hard way that I need to purchase a better pump. My experience has told me that an AC Delco pump actually had a shorter life span than an Air Tex. Therefore, I thought I would ask for other options.

I'd rather find a pump that I can install and just forget about it for a long, long time. Maybe that's wishful thinking.

Casey

[DmaxMaverick]

I understand, but that's one failure and one success, on one vehicle, contrary to the standard. Seems you got a bad Delco, and a good AT. This can happen with any component at any time, to anyone. The Delco pumps, on average, perform vastly better and longer than any other OEM type pump. They usually cost more, for sure, but the "value" is normally in their longevity. Even if you get a "lifetime warranty" component, for less money, how do you value your time, if you have to replace it a few times? If you are getting abnormally short lived pumps, maybe it isn't the pumps. I'd start looking at fuel quality or electrical problems.

With your current problem (this thread), you MUST solve the fuel delivery problem before considering anything else fuel related. Without consistent fuel delivery, everything else downstream won't be right. So far, it's likely the cause of your pump failure, although the pump was likely weak. The lift pump problem probably just pushed it over the edge sooner than it might have, with a good supply of fuel.

All this talk lately about fuel tank socks is hogwash. Pure and simple. There is no difference between a Diesel or gasser sock. Some are more fine than others depending on supplier source, but the fact remains, if this very course screen (even the finest "gasser" version) is plugging up, the problem isn't the sock. Removing it, in favor for a MUCH more restrictive filter, is ludicrous. If you had a problem with plugging socks, then replace it with a filter that's 100's of times more fine, the problem will just be relocated, and probably exaggerated. Forget the sock. If it's plugging up, fix the problem.

[arveetek]

Even if you get a "lifetime warranty" component, for less money, how do you value your time, if you have to replace it a few times?

I agree 100%. I've tried to stop buying "lifetime warranty" parts whenever possible. I've learned that "lifetime warranty" actually means you'll spend your lifetime changing those parts!

With your current problem (this thread), you MUST solve the fuel delivery problem before considering anything else fuel related. Without consistent fuel delivery, everything else downstream won't be right. So far, it's likely the cause of your pump failure, although the pump was likely weak. The lift pump problem probably just pushed it over the edge sooner than it might have, with a good supply of fuel.

Yes, I believe my original DS4 was getting ready to die, and the fuel supply issue finally caused it to crash.

All this talk lately about fuel tank socks is hogwash. Pure and simple. There is no difference between a Diesel or gasser sock. Some are more fine than others depending on supplier source, but the fact remains, if this very course screen (even the finest "gasser" version) is plugging up, the problem isn't the sock. Removing it, in favor for a MUCH more restrictive filter, is ludicrous. If you had a problem with plugging socks, then replace it with a filter that's 100's of times more fine, the problem will just be relocated, and probably exaggerated. Forget the sock. If it's plugging up, fix the problem.

I agree 100% with this too. My sock is still installed and doing its job (I'm not the one with the removed sock).

It appears I've simply gotten two defective pumps (made in Mexico, for whatever it's worth).

Casey

[Burning Oil]

The removal of the tank sock and istallation of a 30 micron filter is what I recomend highly. The tank sock is what 70 micron?
The idea is to make life easier. If your having problems its much easier to replace a spin on filter than to clean a tank sock.
If you are having issues with having a dirty sock then yes that needs to be corrected, but I would much rather deal with a external filter than drop the tank because sometimes the reason for a dirty sock can be ongoing and you may have to drop the tank several times before its cured.

Also, the Walbro FRC10 like I sell is the perfect choice at $139 for the ds4 IP trucks. In all I have sold I have not had a single failure yet.
The ds4 IP needs 9psi and the walbro is delivering a constant 10psi unless at WOT it may drop to 5??

[stezloco]

@BURNINGOIL
my thoughts to your thoughts Mr Spock....
thats a great looking pump ,just the price puts me off. is the fuel pressure that critical that it needs EXACTLY 9 psi? isnt a positive pressure feed still positive?
@dmax
I agree,It is time this thread bit the dust so to speak, and you know what , youre ALL CORRECT...there dont seem to be any wrong ways to filter/deliver fuel...just many ways to 'skin this cat', and there are many ways as we all have said ,some better than others though.
CLEAN TANK+CLEAN FUEL= NO PROBLEMS AMIGO..
I cant agree more about tank removal, it is a ball-ache and PERSONALLY, this is just me, i prefer the out of tank pre-filter or agglomerator idea so i dont have to empty and lug that big tank everytime i suspect a blockage.
all the years i worked on wagons i rarely had problems with fuel pickup pipes (just the things that were put into the tanks deliberately) and none of them had tank socks...draw your own conclusions from all this very good advice ive read here on this subject.....oh ....and dont forget to treat your fuel with BIO-KILL if you are going to stand it for a while, the brown sludge monster will come visit if you dont....ive met him ...
cheery bye...

[arveetek]

Sheesh!

Looks like I stirred up a hornet's nest here!

I decided to stick with a stock pump, and ordered a new AC Delco from Kennedy. John has always been good to me and answered all the questions I've had.

BTW.....Kennedy's price on the Delco pump is as good as most anywhere...including Rock Auto.

Casey

[john8662]

Casey,

I know you've got your OPS bypassed so to speak with the Kennedy setup, but it's powered somewhere different than it would be from factory.

Maybe you've got a low-voltage issue contributing to the pump not operating like it should. Check your voltage at the pump, maybe you've got a not-so-good connection on either side of the poles. I'd suggest power the pump independently of everything you're powering it with now.

Just a thought.

[Kennedy]

The DS4 has a transfer pump internal so it does not "need" any psi let alone 9psi as mentioned. The issue is that when a typical lift pump fails it creates significant restriction in the system forcing the transfer pump to do double duty and reducing the return flow volume (cooling) significantly. This is part of the reason why the PMD's are so prone to fail when mounted on the pump.


John,

My lift pump harness powers the lift pump from a large ring eye and heavy gauge wire totally independent of any factory wiring. You could use this harness on a lawnmower, test bench, or anything with 12v system.

[Burning Oil]

@BURNINGOIL
my thoughts to your thoughts Mr Spock....
thats a great looking pump ,just the price puts me off. is the fuel pressure that critical that it needs EXACTLY 9 psi? isnt a positive pressure feed still positive?
.

The ds4 IP will work the best with any psi above 8. All else being equal by just changing from a stock LP to a Walbro FRC10 you will hear a difference in the engine and fill the improvement on the road. As far as price, Walbro is a better built pump, rebuildable, has optional clear bowl, capable of hot WVO also, holds up to bioD, have not had a single problem with one yet and is $139. Stock a/c delco is $95ish, but only puts out max of 7psi at idle and not rebuildable.


According to Stanadyne's own TSB the ds4 should recieve 9psi. I realize the IP has a transfer pump, but if 0 or 1psi is being delivered via LP the engine will run poorly under load compaired to 6-10psi.
I do agree lack of fuel to IP can reduce the life of the PMD also. IMO even with a good fuel supply the temp swings are just to much for the PMD (mounted on IP) especialy in cold climates. Going from very low temps to engine operating temps several times a day just kills them.

[phantom309]

this works for me,.
14psi or so,. fills the filter real quick it,.cheap too,.



Nick

[arveetek]

I received the AC Delco pump and installed it last night. Right away it primed up quickly and pressurized faster than the previous Airtex pumps. It also ran higher pressure - up to 9 psi. The Airtex pumps put out 7 psi at best.

Started it up, drove about 15 miles, and all seemed good. I noticed pressure dropped off after driving, and was hovering around 3 psi while idling.

I drove to work this morning (22 miles), and she started sputtering and finally died in the parking lot. I had 0 psi now. I couldn't get the pump to pressurize at all. After sitting for a few minutes, I was able to get it to pump up to 9 psi, but after starting the engine, it fell instantly to 0 psi.

I shut it off, primed the system, went to 9 psi, started it up, and it went right back to 0 again.

After sitting until lunch time, it would prime up to 9 and then held around 4 psi while idling. After driving a few miles, it dropped to around 2 psi.

Obviously there is still some restriction in the suction side. It's bad enough that it causes the engine to stall. Neither the electric lift pump nor the transfer pump in the IP is enough to pull fuel from the tank when the problem arises. It appears that the problem goes away after sitting a while. I'm guessing something in the pickup assembly or soft rubber hose is clogging the flow of fuel after a short period of time.

I guess I'll be dropping the tank again! (for a third time)

I'm really going to have inspect the sock. I noticed on my old OEM pickup assembly, the sock was removable. On the new unit, I couldn't get it to come off the pipe.

Casey