Re: Any Diesel Mechanics out there? '95 6.5 TD stalling problem

Greetings,

You have several possibilities here.

First is that you picked up a batch of bad fuel, possibly contaminated with water or algea. I would suggest draining the fuel/water seperator and then replacing the filter again. If it helps for a little while then starts again with the same problems, do it again but add a batch of diesel fuel treatment as well.

The second is that your new lift pump may be on the fritz. Possibly a bad connection or ground and it is only intermittently working.

The third concerns the PMD and fuel injection pump. When you replaced the PMD (aka - FSD or Fuel Solenoid Driver), did you also have the FI pump replaced or rebuilt? If not, then you may need one. One problem is that excess heat from the FSD can also bake the optical sensor inside the pump which will fry the pump and require a replacement. In addition, the heat from the FSD also thins out the fuel which reduces its lubricity and accelerates wear on the FI pump and will also lead to a replacement.

I always recommend that whenever anyone installs either a new FSD or full FI pump that they remotely mount the FSD off of the pump body onto a device known as an "FSD Cooler". This is nothing more than a finned heat sink that the FSD bolts onto and is mounted somewhere away from the FI pump. With this, the heat from the FSD is bled off into the atmosphere and not absorbed into the body of the FI pump causing all of the problems I just mentioned.

The DS4 electronic fuel injection pump is actually a pretty good unit and worked very well on the test bench. But drop it into the V of a diesel motor, keep the FSD bolted to the front and then cover the whole thing with a plastic "Turbo Diesel" cover and you have a formula for heat-related problems. If you end up replacing the FI pump, throw away the plastic cover and remote-mount the FSD.

Cheers - Jonathan

'95 Chevy C3500 1-ton 2wd with a 6.5 Turbo... > > Replaced the PMD, worked just fine... for 5000 miles... > > Replaced the lift-pump before i figured out it was the PMD... > > 2 relatively good batts, new fuel filter, new air filter, no water in > the fuel. > > Runs for exactly 3 minutes, stalls. Restart, 10 seconds, stalls... > over and over. > > It USED to run great, but be hard to start after a fully-warmed > shut-off... I got around that by just leaving it running. > > Just after replacing the PMD, I had no problems at all... it seems > it's getting worse again, just like when the PMD went bad... > > I just bought an OPS, so I'm gonna try that, but I'm not betting on > it... > > Any thoughts? > > TIA! > > -- > Posted using the
formatting link
interface, at author's request> Articles individually checked for conformance to usenet standards> Topic URL: >

formatting link
Visit Topic URL to contact author (reg. req'd). Report abuse: >
formatting link

Reply to
Jonathan
Loading thread data ...

I had the same problem a year or two ago. I replaced the PMD (and remote mounted it with a heat sink that I purchased from ebay) and it worked just fine. Just yesterday, the engine stalled again. I was driving 50 mph and it just stopped. I cursed a little and restarted it. On the way home from work, later the same day, it stalled two or three more times. Today, it did not stall at all. I'm hoping that it's not the PMD again. My truck is a

1995 and it has 245,000 miles in it. With the price of diesel fuel (over $3 per gallon) and the fuel milage that I get (not good), I'm not too convinced that I want to put a whole lot more $$ into it. If I remember correctly, the lift pump is quite expensive and so is the injection pump.

Chip

formatting link
Visit Topic URL to contact author (reg. req'd). Report abuse: >
formatting link

Reply to
Chip

aw get rid of them ??

gimm-e a bottle of carosene k- no ?

naw get some ggoodd fueell dude no 2 ? no 1 ??? where you at ??

heck i change me filter 1 once a month yep that di has a lot of crap in it

Reply to
tudysmuck

You may want to check/replace the PMD wiring harness (connects to the PMD/FSD when mounted on the fuel injection pump, about $20) -- the wiring or connector may have gone bad. Mount the FSD remotely (from the FI pump, that is) to protect both the pump and FSD.

Dirty fuel will give problems to the fuel lift pump, diesel injection pump ($$$$) and the diesel injectors ($$). Install a Racor 645 fuel filter/water separator with a 10 or

2 micron element (around $90) for ease of maintenance and to protect your fuel injection system.

Try slowly removing the fuel filler cap after shutting off the warm/hot engine -- does air get sucked into the filler? If so, your diesel injectors (one or more) may be leaking air BACK into the fuel system causing the hard-start condition, in which case just release the partial vacuum in the fuel tank after every warm/hot engine shutoff.

Do the diesel fuel treatment as Jonathan stated -- high concentrations, several/continuous treatment may be necessary.

Reinstall the fuel lift pump you removed earlier to see if the new one you installed may be the culprit -- check the grounds, or better yet, drill/tap new ones.

Good luck, Franko

contaminated with

seperator and then

while then starts

of diesel fuel

Possibly a bad

working.

you replaced the

the FI pump

problem is that

inside the pump

addition, the heat

lubricity and

replacement.

new FSD or full FI

onto a device

finned heat sink that

FI pump. With

atmosphere and not absorbed

just mentioned.

pretty good unit and

V of a diesel

whole thing with

heat-related

the plastic cover

message

news:1_680402 snipped-for-privacy@autoforumz.com...

PMD...

filter, no water in

seconds, stalls...

fully-warmed

running.

all... it seems

bad...

betting on

standards

formatting link
> Visit Topic URL to contact author (reg. req'd). Reportabuse:

Reply to
Franko

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.