DS4 Problem/ Rebuild Solutions

[scot5146]

Hey Everyone-
So been awhile since I have posted but again I am asking the experts for some advice and direction.

PROBLEM:

Burning up a PMD about every 5 months... Finally got to a tech at Stanadyne and he said my "Optical sensor is going bad so that is what is overheating and burning up my PMD"...

Does this sound correct? I have never heard of that happening...

Also I am now trying to figure out what to do now... I just bought a new PMD to get me buy for a bit but I have 150K on the old Suburban and I am thinking about doing the works on the fuel system.

QUESTION:

What IP pump should I get? New or Rebuilt? Do they have warranties?

If i replace Injection Pump I was also thinking about doing a new Kennedy Duramax Lift Pump, Fuel Strainer Sock [In Tank], DS4 Fuel Shutoff Solenoid, Pre Lift Pump filter [Leroys Diesel]?

What else do I need to replace on a 150K fuel system? Injectors where done less that 20k ago...

Anything else you all can think of please let me know!


Thanks Again


Mike Scott
Firefighter
Vancouver, WA

[twaddle]

Could I suggest that you speak with Gord at North West Fuel Injection, www.nwfuel.ca in Surrey, BC, phone number is 604 882 3835. I have known Gord for a fair length of time back when i used to live in Scotland and since moving to Alberta. He's a handy guy to know and deal with. Give him a call and mention that Jim Twaddle from Evansburg, Alberta gave you his number. Good luck.

Jim
Evansburg, Alberta

[john8662]

Where is your PMD located? Which PMD are you using Stanadyne or D-Tech?

Sounds like BS to me on the optical sensor, that sensor only gives data to the PCM.

I suspect it's where you've got the PMD mounted or the type of PMD you're using.

The grey Stanadyne PMD's are worse than the old black units. They don't live very long at all. The only place I've seen them work is on the side of the pump. On a cooler they all fail quickly.

John

[Robyn]

The tech is feeding you a butt ton of bull, as mentioned, the OS sends info to the computer.

The PMD is controlled by the computer.

The PMD is basically two large power transistors that control the fuel solenoid in the IP

There is a large amount of heat generated in the PMD and it must be carried away, or the transistors and some of the other light components in the PMD get COOKED :eek:

Get a Dtech PMD , change the harness on the IP to accept it and mount the DTECH out of the engine bay on a cooler.

Extension cables are readily available.

The gray Stanadyne units are a POS
I have seen several fail after only a short time.

Another thing you need to check is GROUNDS

Be sure the PMD harness ground is on the IP AND NOT elsewhere.

Check your main harness grounds at the rear RH corner of the intake.
Make sure of the Battery grounds, they must be good and the both cables must be good.

Looks can fool you, as these cables corrode deep under the side terminal jacket.

Bad connections, especially grounds can drive the electronics NUTS, plus cause back-feeding that can destroy delicate electronics.

Having poor voltage (read this as low) at various points along the system causes the amperage draw to go into the ozones.

The PMD is fed by very small sized wires, so this alone can limit power flow.

Keep in mind that the dual battery system must be in top shape to function correctly.
The alternator feed is spliced into one + cable, and if the cable is getting crappy inside, the voltage and amperage can fall off dramatically.

Missy

[scot5146]

Well thanks for the info everyone, sorry it took me a few days to post again I just got back from hunting yesterday...

Anyway I have been using the D-tech PMD's with a long extension mounted down in the bumper. Its been like that since the first one went out a few years ago.

I looked at it again yesterday and noticed I am leaking diesel and cant figure out where, it has never done this before... It seems like it coming out from under the fuel filter housing somewhere...

Where is the fuel shutoff solenoid? Could this be leaking or bad, can it cause my PMD problems?

Also how do I test the alternator to make sure its good? Both my batteries are less than a year old?

Thanks again for the info

Mike Scott
Firefighter
Vancouver, WA

[Kennedy]

We've been selling brand new DS4 pumps more than reman these days. Then you don't get reused optic sensors, shutoff solenoids etc. You also get the best PMD/FSD available as far as I am concerned.



I'd be curious to see a picture of how you mounted the module and what you mounted it to. So many times I find people just slapping them to undersized heat sinks, pieces of flat metal, or worse yet nothing at all.

[scot5146]

I'd be curious to see a picture of how you mounted the module and what you mounted it to. So many times I find people just slapping them to undersized heat sinks, pieces of flat metal, or worse yet nothing at all.

I will take a picture and upload it, I would appreciate the input...

Thanks

Mike

[scot5146]

Hey y'all

Well I have not had a chance to take a picture of the PMD mount and location yet but I will as Kennedy asked...;)

I am leaking diesel from somewhere on top the engine??? The filter looks ok, all line to and from it look ok...

I am at a loss here???? Any ideas? Also it seems to leak only when running. If I turn it off and release the pressure in tank it stops soon after.

How much pressure should be in the tank when releasing the cap?
This is a new problem aside from trying to figure out why I am burning up a PMD every 3 months...

Thanks Again

Mike

Firefighter
Vancouver, WA

[Robyn]

The filter housings are notorious for rotting through in the heater in the bottom.

My bet is that the fuel is leaking out past the wires that enter the very bottom of the filter unit.

You can replace the heater assembly, but a nice Racor with a spin on filter mounted up front near the ABS module works sweet.

Just add a bit of line extension and connect the feed line over to the IP and your set.

You can remove all the hose down under the intake too.
The Racor has a water bowl on the bottom with a drain.



I have used the Racor 230 R2 ASSEMBLY and it is just right.


Good luck

Missy

[scot5146]

The filter housings are notorious for rotting through in the heater in the bottom.

My bet is that the fuel is leaking out past the wires that enter the very bottom of the filter unit.

You can replace the heater assembly, but a nice Racor with a spin on filter mounted up front near the ABS module works sweet.

Just add a bit of line extension and connect the feed line over to the IP and your set.

You can remove all the hose down under the intake too.
The Racor has a water bowl on the bottom with a drain.



I have used the Racor 230 R2 ASSEMBLY and it is just right.


Good luck

Missy


That may be exactly the spot thats leaking, it was looking as if the fuel was past the wires.

So if I mount the Racor, do you delete and remove the stock filter housing?

I like that idea alot, what about the Duramax filters? Which is better or cheaper?

Thanks

Mike

[Kennedy]

At one time I thought Peninsular had a ton of the OE fuel filter housings as new take off.

[phantom309]

some good options in this thread,

http://www.thedieselpageforums.com/tdpforum/showthread.php?t=42183

personally if i was to step up further to a more powerful high volume pump, i,d delete the sock in the tank i think it would collapse under high suction, and i,d add a pre-filter somewhere in the first 2 ft of line before the lift pump,.
JMHO,.

Nick

[scot5146]

That is a really good thread... The pictures help pull it all together, I would like to know waht the costs were to assemble a filter/ LP pump system like that?

What do you do with the sensors in the OEM filter housing and the wiring... IE: water/fuel sensor, etc...

I have a 99 k2500 Suburban

Thanks

Mike

[scot5146]

some good options in this thread,

http://www.thedieselpageforums.com/tdpforum/showthread.php?t=42183

i,d delete the sock in the tank i think it would collapse under high suction, and i,d add a pre-filter somewhere in the first 2 ft of line before the lift pump,.
JMHO,.

Nick

How do you filter the big stuff in the fuel in the tank if you delete the sock?

[phantom309]

well you don't filter the "big bits" in the tank anymore,. you run a pre-filter before the lift pump and filter the "big bits" there,. makes servicing much easier,.
Ends up being like a commercial diesel fuel system.

[scot5146]

Ahhhh...


Got it, that's what I was figuring... The last part I am confused on is if I replace the stock filter housing and go with a racor or similar, what do I do with the fuel heater element that is plugged into the bottom of mine. Will i trip a code if it is unplugged or removed?

Thanks Again

Mike

[phantom309]

Ahhhh...


Got it, that's what I was figuring... The last part I am confused on is if I replace the stock filter housing and go with a racor or similar, what do I do with the fuel heater element that is plugged into the bottom of mine. Will i trip a code if it is unplugged or removed?

Thanks Again

Mike

No,...

[DmaxMaverick]

Ahhhh...


Got it, that's what I was figuring... The last part I am confused on is if I replace the stock filter housing and go with a racor or similar, what do I do with the fuel heater element that is plugged into the bottom of mine. Will i trip a code if it is unplugged or removed?

Thanks Again

Mike

No codes, no complaints. You can also choose a Racor (or other brand) filter assembly that has a heater.

[scot5146]

Which Racor filters and housings would you all recomend for both pre lift pump and up on top near the IP pump?

I am going to upgrade to a kennedy Duramax lift pump as well, and probably remove the sock in the tank...

Thanks for all the advice

Mike

[scot5146]

Ok so I am going to start at the tank and head to the IP... This is my plan...

1] Drop tank, clean, remove sock

2] Racor 20 micron filter before the lift pump

3] Replace LP with Kennedy Duramax LP pump

4] Racor filter with heater at top of motor

5] Remove the stock filter housing and delete as well as any hoses available.

6] New fuel shutoff solenoid and Walking J "feed the best fittings kit"
I am hoping this will update my crapy stock fuel system and eliminate the leaks I am having...

While I am in there I am planning on putting in a new stanadine PMD harness from the IP. Hope that this will stop or slow down my 6 month PMD decline and replacement of which I am now on my 5th PMD...


Any help/ Instruction or advice on my plan would be appreciated; I am planning on staring this in the next month...

Thanks again for all the Input and Help!!!

Mike Scott

Firefighter
Vancouver, WA

[DmaxMaverick]

I do not recommend complete elimination of the in-tank fuel inlet sock. Clean or replace it as necessary, but it's there for a reason. The only caution here is some aftermarket socks are not ideal for use (mesh too soft, small, and/or without a bypass valve).

Any accumulation of normal/incidental debris will block the small tubing. Something as simple as an air-soft BB, a marble, or "normal" debris in the tank will shut it down completely. One flake of rust, paint, or a piece of paper will do the same.

There's nothing wrong with adding a 20 micron filter prior to the lift pump, but keep the sock. Fuel tank socks rarely ever fail, even in 30-40 year old vehicles. They are a preventative measure, and an indicator of other failures. If your sock is plugging up, something else is wrong, and the sock is doing its "job".

[scot5146]

If I were to replace it, were can I find a good one... [Sock] Can it just be cleanned and replaced? Also my fuel guage is not very accurate, is it a fuel sending unit in the tank or a different sensor type for the fuel guage?

Thanks

MIke

[DmaxMaverick]

A new sock will come with a new sending unit. Some aftermarkets are less than ideal (as described above). The sock can be purchased separately, from GM and other sources. LMC Truck, maybe. If your old sock is still serviceable (not brittle or damaged), it can be cleaned and reused. Most that I've seen have been good, even after decades and 100's of thousands of miles.

GM fuel level senders are notoriously inaccurate. The gage is a "dumb" indicator, in that they only report what they are "told". They indicate fuel accurately enough, but are rarely ever linear. You can "adjust" the float, but they will never be accurate without a lot of work (guesswork, trial and error, etc.). We had a member/vendor here that has/had a transducer kit that should be extremely accurate, but I haven't seen them mentioned in a while.

[phantom309]

I

Any accumulation of normal/incidental debris will block the small tubing. Something as simple as an air-soft BB, a marble, or "normal" debris in the tank will shut it down completely. One flake of rust, paint, or a piece of paper will do the same.

.

I totally disagree,. first of all what the heck are you putting in your tank for fuel?? and where is it coming from? a pond?
secondly there will not be "normal debris build up" the fuel and "debris" is getting sucked into the filter,.it builds up in a tank with a sock, the sock acts as a barrier trapping debris in the tank until the sock is so saturated it fails,.why carry the debris (as you describe it) in the tank? let it pass to the primary filter before the lift pump where it can be removed with regular filter changes,.
Can you imagine just how big the debris would have to be to completely shut off the intake pipe? a 5/16ths hole?

Urban legend i think,.how would an airsoft BB get in my fuel tank? it,d have to be huge flakes of paint,. or rust,. and how the heck is it getting in there?? or paper or any other oversized contaminant,.it,s a diesel fuel tank, it doesn't promote rust that well,. A marble?? i doubt the pump could lift and hold it in place,..


i can only see 1 way and that's sabotage,.
JMHO

[DmaxMaverick]

I totally disagree,. first of all what the heck are you putting in your tank for fuel?? and where is it coming from? a pond?
secondly there will not be "normal debris build up" the fuel and "debris" is getting sucked into the filter,.it builds up in a tank with a sock, the sock acts as a barrier trapping debris in the tank until the sock is so saturated it fails,.why carry the debris (as you describe it) in the tank? let it pass to the primary filter before the lift pump where it can be removed with regular filter changes,.
Can you imagine just how big the debris would have to be to completely shut off the intake pipe? a 5/16ths hole?

Urban legend i think,.how would an airsoft BB get in my fuel tank? it,d have to be huge flakes of paint,. or rust,. and how the heck is it getting in there?? or paper or any other oversized contaminant,.it,s a diesel fuel tank, it doesn't promote rust that well,. A marble?? i doubt the pump could lift and hold it in place,..


i can only see 1 way and that's sabotage,.
JMHO

I never said I would put any such thing into my tank. Perhaps a disgruntled prior associate might, a prankster, a kid in a parking lot (or at a fuel station), a PO'd neighbor, etc. Rust happens. Tank coatings (paint was a bad example, but essentially the same thing), do flake off, and flakes (of whatever) do accumulate. Diesel fuel, over time, will scale the walls of a tank (seen that hundreds of times). Who knows the long term affects of "new" fuel formulations? I've repaired/replaced plenty of fuel tanks over the years. You would be surprised, as it seems, what may be found in the tank of some 30-40 year old vehicles. Your "5/16" hole is quite small, compared to many things that it may encounter. The inside diameter is smaller than that at several points, including bends and weld points. Also, the distance from the end of the tube to the bottom of the tank is short enough that a marble (or similar object, don't be so literal) can meet the end of the tube. A "dented" tank changes the rules, as well. If it's a "soft" object, it can become lodged in the inlet. The pump WILL draw up something such a marble. Some plastic marbles (plastic balls resembling marbles) are neutrally buoyant in Diesel fuel, so in that case, it wouldn't matter where the intake pipe was. A rubber ball would be worse. These items can be found in some children's games, and many other "common" places. A beetle crawled into the nozzle at the fuel pump would plug it up, just the same. Do you inspect the entire nozzle pipe when you refuel, every time? I know I don't. Blockages don't have to be "permanent", they only have to block the flow long enough to shut you down once, long enough to create a very bad situation, such as a busy highway in front of an impatient big rig driver.

The sock doesn't "filter" fuel, in almost any sense of the word. It's a first line defense against what "might" happen. The sock does more than strain the fuel, it also decreases the velocity of the fuel as it first enters the fuel system plumbing. This alone can, and will, prevent many "what-ifs" that may occur otherwise.

Fuel inlet socks add to the cost of vehicle manufacture. If they weren't really necessary, every vehicle brand (that I've seen) wouldn't be installing them. They may even be required by law in some places, but I don't know that.

Eliminate your sock if you must. I don't think it's good advice to suggest others do it, unless you want to become their warranty and insurance department.

[phantom309]

I never said I would put any such thing into my tank. Perhaps a disgruntled prior associate might, a prankster, a kid in a parking lot (or at a fuel station), a PO'd neighbor, etc.
Sabotage as I said.


Rust happens. Tank coatings (paint was a bad example, but essentially the same thing), do flake off, and flakes (of whatever) do accumulate. Diesel fuel, over time, will scale the walls of a tank (seen that hundreds of times). Who knows the long term affects of "new" fuel formulations? I've repaired/replaced plenty of fuel tanks over the years. You would be surprised, as it seems, what may be found in the tank of some 30-40 year old vehicles.
If the vehicles have sat for extended periods of time i don't disagree that the tank will become scaly and full of algea, mostly on steel tanks tho,.
but a daily driver,. no.


Your "5/16" hole is quite small, compared to many things that it may encounter. The inside diameter is smaller than that at several points, including bends and weld points.
Still ,. the size of debris we are talking here would have to be introduced by sabotage, retail fuel stations have filters on all the lines.


Also, the distance from the end of the tube to the bottom of the tank is short enough that a marble (or similar object, don't be so literal) can meet the end of the tube. A "dented" tank changes the rules, as well. If it's a "soft" object, it can become lodged in the inlet. The pump WILL draw up something such a marble. Some plastic marbles (plastic balls resembling marbles) are neutrally buoyant in Diesel fuel, so in that case, it wouldn't matter where the intake pipe was. A rubber ball would be worse. These items can be found in some children's games, and many other "common" places. A beetle crawled into the nozzle at the fuel pump would plug it up, just the same. Do you inspect the entire nozzle pipe when you refuel, every time? I know I don't. Blockages don't have to be "permanent", they only have to block the flow long enough to shut you down once, long enough to create a very bad situation, such as a busy highway in front of an impatient big rig driver.
So literal? i used your description not mine,. now you have added other possible contaminants into the equation ,.a beetle crawling into the end of a fuel delivery nozzle? I don't see much insect life near diesel fuel at any time,. pretty toxic enviroment for them. I,m sorry but in my opinion you are definitely grasping at straws.



The sock doesn't "filter" fuel, in almost any sense of the word. It's a first line defense against what "might" happen. The sock does more than strain the fuel, it also decreases the velocity of the fuel as it first enters the fuel system plumbing. This alone can, and will, prevent many "what-ifs" that may occur otherwise.
The area of the sock must be 10X the inlet pipe size, i can't see the sock slowing velocity, unless it is partially blocked with debris. The cure for that problem is to drop the tank,. which leads back to my original point that having any sort of strainer inside the tank is a pain in the butt to service,



Fuel inlet socks add to the cost of vehicle manufacture. If they weren't really necessary, every vehicle brand (that I've seen) wouldn't be installing them. They may even be required by law in some places, but I don't know that.

Eliminate your sock if you must. I don't think it's good advice to suggest others do it, unless you want to become their warranty and insurance department.

Fuel inlet socks are a cheap way to circumvent the cost of a decent replaceable primary filter ahead of the fuel pump

I have eliminated my sock in the tank.
I will put forward my opinions regardless of whether you agree or disagree with them.
The readers of this forum are all grown men and capable of deciding what is best for them based on the opinions of the other members.
I doubt there is much warranty left on any vehicle/engine combination that ceased production over 13 years ago.

Nick

[DmaxMaverick]

.......................
The area of the sock must be 10X the inlet pipe size, i can't see the sock slowing velocity, unless it is partially blocked with debris. The cure for that problem is to drop the tank,. which leads back to my original point that having any sort of strainer inside the tank is a pain in the butt to service,
......................
Nick

Simple physics. The surface area of the sock is many times (a LOT more than just 10X) that of the inlet pipe. The same volume of fuel traveling through the inlet pipe cross-sectional area will be approximately the differential fraction of the sock surface area. So, yes. The velocity is significantly slower through the sock, than through the inlet pipe. This condition, in itself without any help from any other condition, will reduce the blockage potential.

The remainder of the discussion, I'll leave it to the end-user to decide. It is, afterall, arguably, arguable.

[Kennedy]

I had a Dmax in that had a kernel of corn stuck in the outlet fitting of the sending unit. Apparently dried corn does not get soggy in diesel.

Leave the factory sock in place. It will keep the bottle caps and foil bottle seals off the end of the tube. Just avoid the gas engine socks and you'll be fine.

[scot5146]

Heated discussion!;)

Thanks everyone for the advice and opinions, I am going to have to agree with Dmax and Kennedy on this one... Not necessarily because I agree but because both of you guys have given me very solid advice over the years and I respect your opinions. I do see the rational that Nick is speaking of however...

But I would rather error on the side of caution. I am going to clean or replace as needed the sock in the tank just to be safe.


I appreciate all the input from everyone!:D


Thanks Again For the Help


Mike

Firefighter
Vancouver, WA

[More Power]

The gray Stanadyne units are a POS
I have seen several fail after only a short time.
Missy


Hmmm.... That's not what I've been hearing from 6.5 owners who call or send me an email. I'd be curious to know how many of the grey modules have failed for members here.

On another subject... The fuel tank sock is also the first line of defense for water. The fabric is designed to resist water passage, though it will get through if the sock is mostly submerged in water.

[phantom309]

Heated discussion!;)

Thanks everyone for the advice and opinions, I am going to have to agree with Dmax and Kennedy on this one... Not necessarily because I agree but because both of you guys have given me very solid advice over the years and I respect your opinions. I do see the rational that Nick is speaking of however...

But I would rather error on the side of caution. I am going to clean or replace as needed the sock in the tank just to be safe.


I appreciate all the input from everyone!:D


Thanks Again For the Help


Mike

Firefighter
Vancouver, WA


It all boils down to "Do what you want, your going to anyway" too many cooks etc,..

I am maybe a lot more careful fueling my truck up than some other folks,.
Maybe people that get foreign objects in their fuel tank would benefit from a drop in fuel strainer, just for those careless moments,.

:D

[scot5146]

Do I need to worry about not having a fuel heater anymore if I put in the racor filters? It doesn't get below freezing in Vancouver WA very often...

Mike

[phantom309]

Do I need to worry about not having a fuel heater anymore if I put in the racor filters? It doesn't get below freezing in Vancouver WA very often...

MikeMy personal experience,. I've been working in Alberta the last few winters,. the old truck has gone through some fairly harsh weather colder than -30c quite a few times,,I do not have a fuel heater on the truck anymore,and i haven;t had any problems,. i do like to add Howes fuel conditioner in the winter,.

Nick