VERY DISAPPOINTED WITH FSD DRIVER / COOLER [Archive]

turbovair

10-27-2003, 09:49

I know, each time I had my truck in for a pump/FSD I asked about that modification and was told that doing it would void the warranty. So, I left the FSD mounted to the pump. All my pumps were changed at dealer expense. Now I'm over 100,000 miles and it doesnt matter. After reading your post I'm not totally convinced its even worth the money, except for ease of replacement.

Bobbie Martin

10-27-2003, 10:30

The warranty depends on your dealer. Back when our Suburban was in warranty, I had the PMD replaced under warranty while it was on a FSD cooler. On fact, the dealer gave me a PMD and let me do the swap. I just had to return the bad PMD. If the dealer wants to warranty it with a FSD cooler, they can. If they don't want to, they won't. Don't believe the BS about the "factory service guy". The only person that sees the engine is the mechanic that works on it and I'm sure most of them would rather change it when its on a FSD cooler. They certainly won't mind getting paid the three hours or whatever it is for 30 minutes worth of work.

BTW, I do agree with turbovair - The main benefit of the FSD cooler is you can change the PMD in less than 30 minutes. If you have a DS4, its definitely worth the money for that reason only! When you get tired of putting up with a DS4, get a DB2 and put the PMD where it belongs - the trash can!

turbovair

10-27-2003, 10:43

Bobbie, you bring up a good point about the DS4. However, here in Phoenix we have annual smog inspections. How would "opacity" readings change?(beam of light through your exhaust) Would the truck be emissions dirtier? Wouldnt even consider it if I didnt believe I could get through emissions test.Thats what we face here in Phoenix.

Brandon

10-27-2003, 12:07

The emissions test is easy to pass in Phoenix I do it every month. Your the one that does the test so don't push the pedal all the way down in a hurry. The testers don't know any different. I am running 80 mm of fuel on my personnal truck without the cat and it passes every time. A good station to go to is the one at greenfield and mckellips. (a bunch of burned out light bulbs work there.)

96ccdd

10-27-2003, 13:30

Well on a good note the dealer I buy parts from is getting me a new PMD for $233.

Bobbie Martin

10-27-2003, 15:51

Not sure on the smog test. With the DB2 you can adjust the fuel mixture. So I guess if it did not pass, one might do a little tuning to give less fuel. A throttle stop might do the same? In Florida they use to have smog test. We had to take the diesel Sub every year. $10 for the test, they put it on rollers and ran it up. Trouble was, there were no diesel specs, so every diesel automatically passed!

GARY PAGE

10-27-2003, 16:32

At this time I don

Turbine Doc

10-27-2003, 17:23

Mark,
About 9 mos after mounting my FSD on a plate mine started acting like it was going like the 1st one, I called Kennedy to see what the story was on post plate failures he said it happens but he also asked if I packed the cavity around the transistors with di-electric grease, he said in his opinion it helped with heat transfer to the plate, I had not. I filled the cavity with the grease and knock on wood, it hasn't acted up again in 14 months. Of course now that I said that it won't run next time I need it.

Gary as far as few failures on Hummer, I think what is killing us is post shutdown and idleing in traffic with low air flow. Hummers have louvered hoods that let some of the heat escape that we don't have. One day I ran a experiment with a thermocouple under the hood, post shutdown under hood temps went to 180F in short order at Inj Pump valley following shutdown.

Just a theoy but all that extra heat can't be good for transistor which generates it's own heat under load anyway. When running and proper air flow under the hood temps at FSD cooler plate mounted on drivers side fender never got over 118, when stopped in traffic temps went to 130, post shutdown temp 160 at plate. I lost my written results in a computer crash and also in forum's crash or I do a search; so numbers are from ever aging memory. Maybe I need to run experiment & get data again.

[ 10-27-2003, 04:36 PM: Message edited by: tbogemirep ]

ucdavis

10-27-2003, 17:24

Gary,
FSD may solve your trouble. If not, I'll bet you two bucks it is the injection pump. Sounds just like what happened to mine (35 always, sometimes 36 and sometimes 17 and/or 18 too). New FSD did nothing, but new IP & it runs like new. I changed out the PCM cuz it was a helluvalot easier than the IP, but to no avail (was told by a seasoned service writer who had nothing to sell me so I believed him that some of the '95s had bad PCMs, but that the majority of these troubles were caused by pumps; he was right on my rig).

StephenA

10-27-2003, 18:08

Golly Gee- with all this FSD failure stuff, I'm surprised no one has fitted a thermoelectric heat pump to the son of a gun. My 92 is mechanical, but if I had all the problems the electronic injection folks have been going through, I'd slap a heat pump on it and never look back...

[ 10-27-2003, 11:30 PM: Message edited by: StephenA ]

HowieE

10-27-2003, 18:37

Gary
In my research for my posting "GM Recalls & FSD Problems" I had the same conversation with Stanadyne. Stanadyne would like to take the position that it is a GM computer problem. It realy doesn't matter who or which part created the problem the fact is our trucks are not reliable and notifing the DOT in mass is the only approach remaining for those of us that are over 120,000 miles and intend to keep our trucks.
If you agree give them a call 888 327 4236
As for living in AZ and having several pumps replaced and taking the dealer word it was the pump that failed who can be sure. If you have 2 components in a failed system without any other means of singling out which has failed you have to swap out one with a known good part and retest to be sure which one was the cause of the failure

dslpwr

10-27-2003, 18:42

I WAS TALKING TO BILL HEATH LAST WEEK.
HE CLAIMS HE HAS OVER 300,000 MILES ON HIS DESIGN.
IT MOUNT ANY WHERE AS LONG IT IS NOT IN THE ENGINE COMPARTMENT.
IT COMES WITH 6 FEET WIRING HARNESS.
I HAVE ONE ON MY TRUCK, TIME WILL TELL HOW LONG IT WILL LAST

GMCfourX4

10-28-2003, 11:20

I paid a lot of money to get Kennedy's FSD cooler and a new PMD when mine went (I had the pump replaced by the dealer, then put on the new FSD&cooler as soon as I got it home, leaving the other one unplugged on the pump....) It lasted maybe 6-8 months, then just died. For over a year I have been running with the other PMD mounted on the pump, and no problems. I called Kennedy, and he told me the Stanadyne warranty was 90 days or something, and basically that I had wasted $430, or whatever it was. I'm contemplating getting an extension harness and a new PMD, and mounting it so that the heatsink is in the path of the intake air, like others have suggested. I also noticed that when the PMD on the cooler died and I switched back to the pump mounted (dealer installed) one, the truck ran a lot stronger. Am I crazy, or has anyone else experienced this?

-Chris

turbovair

10-28-2003, 13:05

Ive had relatively good luck with PMD's mounted on the pump.It doesnt get much hotter than here in Phoenix in the summer. I personally dont think heat is the only thing to be addressed in the PMD scenario. There must be something else.Just wish I knew what it was.

StephenA

10-28-2003, 16:55

If anyone wants too, we could take a look at a bunch of bad units and verify exacty what's failing on them. Shouldn't be too hard- it's just a circuit board with chips & discrete components, right? Compare a few of them with a working unit, and we'll know why they fail. If they're potted, we'll get out the dremel...

pannhead

10-28-2003, 17:18

i too have lost a fsd on a cooler mounted to manifold...since i mounted inside cab i've had no problems ever since...i think post shutdown heat-soak is a killer....STEPHEN, if you can get thru that nasty impossible epoxy without destroying what we all want to see, you will become the Super-Duper DP Member of the decade :D ..i know alot of people have tried it and failed,so have i....almost lost what little sanity i have left smile.gif

turbovair

10-28-2003, 17:25

Gotta agree with Pannhead here too...could have hero status. But then, if someone could get the print...A GOD?

Jim P

10-28-2003, 17:27

I mounted my pmd in front of the radiator. It never even gets warm.

I never thought mounting it to the intake was very smart. Heat rises.

Here is some pics of mine if anybody is interested.

www.myweb.core.com/photos/jpfarmer@raex.com/95chevy2500hd (http://www.myweb.core.com/photos/jpfarmer@raex.com/95chevy2500hd)

Jim P

10-28-2003, 17:36

Sorry I screwded up the url of the pics. Here is the right one

http://myweb.core.com/photos/jpfarmer@raex.com/95chevy2500hd

turbovair

10-28-2003, 17:38

OK, after monitoring this site for a couple years, I have a couple of ideas...
1.Need to determine what exactly is contained in a PMD and replicate/improve it no matter what the resultant size.Either by dissasembly or by getting hands on a "print".
2.Lobby "Painless Wiring" to develop an improved wiring harness (posssibly with additional ground points)for the 6.5 so as to take harness problems totally out of the equation.
I think these two items explain at least 70% of our problems.

pannhead

10-28-2003, 18:12

JIM P....your FSD is cool as a cucumber smile.gif

pannhead

10-28-2003, 18:28

TURBOVAIR is right....i wonder how many of us (including myself) have thrown parts and $ at a problem that can be traced to bad wiring electrical gremlins....i luv to hate this truck :mad:

GARY PAGE

10-28-2003, 18:49

Hey panhead I agree, see my post on Electrical Analysis, we need to understand more.

kowsoc

10-28-2003, 21:31

I also agree that heat is not the real killer of these FSD's. After I had one fail I thought I'd try to make it work again by replacing the two power transistors. Since they do all the heavy work on the unit and create all the heat, I thought one or both of them were fried. The FSD would not work. Some other circuitry deep inside the epoxy was to blame.

Usually when the FSD fails it will work again after a cool down period and intermittently operates after that...almost like a bad connection or solder joint in the unit. This leads me to my theory that the CHANGES in temperature that the FSD experiences causes physical stress on the components and soldering on the circuit board in the epoxy. Over time this may stress the components causing broken solder joints and intermittent connections. Maybe the epoxy expansion rate is different than the circuit board and components soldered to it....I don't know. I think this is why the FSD's should be mounted away from the engine compartment to avoid high temperature extremes from heat-soak.

I too have tried to discover the secret circuitry in that epoxy....nearly impossible...no success.

Someone told me once that the FSD is a simple push-pull power amplifier. It most likely could be built cheaply with more robust components that would never fail. Maybe mine won't fail again ;) . Sorry for the long post.

StephenA

10-29-2003, 05:40

Sorry for the delay- been up in the mountains. OK, so many folks have tried & died grinding away the potting material. I could have guessed this with all the trouble this thing causes. I'm no hero, but if anyone wants to send me a bad unit that's not chewed up yet, I'll take it to my dentist & have it xrayed. Then we can grind with a map. The new thread on this could be fun.

[ 10-29-2003, 05:20 AM: Message edited by: StephenA ]

turbovair

10-29-2003, 10:48

Is there anything on this planet that could DISSOLVE the potting material without destroying the electronics?

advanracing62

10-29-2003, 11:42

I just ordered the cooler from Kennedy as well as the extension harness. I plan on putting the FSD in the cab and running a cooling fan on it. I think I will have it thermally controlled and try to keep the FSD at about 80-100* for the most part.. So far from what everyone here has said this seems to be the safest way to run the FSD/cooler

moondoggie

10-29-2003, 12:46

Good Day!

turbovair: See my 17 Jul 03 post in Dead PMD's wanted.. (http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=004230#000003).

Blessings!

Brian Johnson, #5044

timwagner6

10-29-2003, 13:49

Still need a dead PMD? Call me at 231-598-1227.
I think I have one.

Tim

vernj4

10-29-2003, 14:01

The other day the charging circuit on my JD 420 tractor lit up.........went to the dealer for advise and counsel......the tech spoke about checking the ground.........made a real point that electronic circuits must have a GOOD ground to perform reliably and not just a so-so ground.

I think I read a post by moondoggie regarding grounds........how he takes special precautions by adding star washers, etc. I think this is a great suggestion.........something that we all can check out and update as necessary.

Cowracer

10-29-2003, 14:36

I will bet money that when we finally crack one of these open, we will find just a push-pull transistor setup with some really big power transistor.

The ECM makes all the signals that the pump needs, but not at the power level required.

I will also bet that the circuit keeps a volt or two of bias across the Fuel Solenoid at all times. That way, the ECM can detect when the solenoid closes with the back EMF of the closing solenoid. This is the dreaded fuel pulse width too long (or short) that set our favorite codes.

any takers?

Tim

BurbantoBioD

10-29-2003, 17:20

Mounting the FSD in the grill in front of the radiator what about rain? Are the PMDs water tight? I mounted mine with a fan to the left of the brake pedal on a bracket from the body.

StephenA

10-29-2003, 18:57

I'm with you Tim- I'll bet it's just an it's an amp...
Never saw anything that would eat potting material, but with an x-ray or map, it's usually not to hard to dremel down to the actual traces & components. The tough part is getting the part numbers, but if it's just an amp, that doesn't matter. If we could monitor both input & output, we'd know what it is.

moondoggie

10-30-2003, 04:24

Good Day!

vernj4: Here's my topic about grounds (http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=004386#000000).

You guys are really ruining my day. I sure wish I hadn't given up & tossed my dead FSD.

Blessings!

Brian Johnson, #5044

moondoggie

10-30-2003, 07:22

Good Day!

Might it not be a good idea to somehow combine VERY DISAPPOINTED WITH FSD DRIVER / COOLER & PSD Electaical Signals?

Blessings!

Brian Johnson, #5044

StephenA

10-30-2003, 08:17

Good idea, Brian... Jim?
Also, Brian- did you call timwagner6 above on the bad unit? I believe he was offering it to you. If you don't want it- I'll call.
BurbantoBioD : the unit is potted, so it's waterproof- but the connections...
Once (& if) we crack this sucker, placement won't be so important. It's just a bad design.

moondoggie

10-30-2003, 10:02

Good Day!

StephenA: Go for it. There

turbovair

10-30-2003, 11:47

How about creating a new thread " Lost Secrets Of the Mysterious PMD",or "Discovering whats inside a PMD/FSD"??

Jim P

10-30-2003, 14:54

I have a machine shop here at home and if someone would send me a junk pmd, I would be willing to mill out the potting material. I would just keep taking cuts of .010" or so until I find out what is in there.

StephenA

10-30-2003, 17:40

Ok Brian- I'll call. Let's try to collect several, so I can X-ray, Jim P can mill, & anyone who wants to grind can have a go...
Who's gonna start the new thread... Gary, you still there?

G B Sisson

10-31-2003, 00:15

I just posted a reply similar to this on thethread about PMD resistors,but this has more to do with mounting.Im looking to move my cooler off manifold so called Bill Heath to get his6' "extension cord". I ended up buying his whole remote setup. This he suggests mounting to my skid plate,his favorite spot on 4wds. I had wantedto carry a spare (maybe Ive been spending too much time reading about stalling 6.5s) PMD anyhow. I was wondering why I havent seen anything about mounting it there before. He agrees vibration could be a big part of failure and says his plate is enginered to reduce vibration. One BIG difference from what Ive been reading is he uses a Boeing formulated epoxy between PMD and plate..Sort of hard to remove and how about heat transfer? He has done all this since 94 with good results. So far all I know is since I replaced PMD and put it on a cooler, She runs like a top and hasnt stalled or hesitated in 300 miles....just hoping to keep it that way with a cooler mount ....Thanks a lot for all this info... Gary 94 2500 4x4 Burb,with a" 6.5 Diesel Turbo" hood decal on the tailgate