Got a cicumstance that I would like some input.
Cruising on a 200 mile trip, car running great, 70 mph, and started losing power down to @ 45-50, felt as though it was jerking running uphill, then started running fine. It has new fuel filter.
Next day, starts right up.
I'm open for any suggestions. I thought, could it be the fuel strainer in the tank at the fuel line outlet.?
Thanks in advance.

Does it have both new fuel filters? Even if both are new, I'd try replacing them before going for the strainer. One way to test if the strainer is plugged is to switch the output and return lines and let the engine suck on the return line for a while to see if it gets better flow.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Which fuel filter did you replace?

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Both filters were replaced. Thanks for the questions. I'll try the fuel line swap and see what happens.
On a side note. To the left of the fuel guage, what is the amber triangle laying on its side?
Thanks.

Low fuel indicator light.

Also check your primer pump. Air intorduced to the system will cause the symptoms also. Also check the air bubble in the primary filter. If it gets bigger, there is air getting into the fuel system. I had a primary filter develop a crack, and when the engine was running, would allow air into the fuel system, and it would not run well at all, except at idle.

__________________
RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Possibly some bad fuel? Or a lot of water? Was it cold enough wherever you are to have froze some water? Or fuel gelling a little?

I've got to ask the dumb question; check if the air bubble gets bigger. I'm lost now. Please explain.
Thanks.

You know, it could be some water in the fuel. It had been sitting a little while.
I guess I was jumping to the worst case senerio.
Thanks.

I believe the filter in question is the clear plastic one thats on the fuel line going to the injection pump. Not the screw on oil can type filter. You should see a small air bubble at the top of the clear filter. If that bubble increases substantially in size it might be an indication of air in the fuel system somewhere.

- Peter.

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2021 Chevrolet Spark
Formerly...
2000 GMC Sonoma
1981 240D 4spd stick. 347000 miles. Deceased Feb 14 2021
2002 Kia Rio. Worst crap on four wheels
1981 240D 4spd stick. 389000 miles.
1984 123 200
1979 116 280S
1972 Cadillac Sedan DeVille
1971 108 280S

With the engine at an idle look at the primary filter. You should see an air bubble. It is normally there, even when you shut the car down. While you are looking at the air bubble, manually move the accelerator linkage to raise the engine speed and hold it there. Watch the air bubble, if it gets bigger, air is getting into the system.

Also, when you fuel up, is there a "whoosh" type noise when you remove the fuel cap? A tank under vacuum will also keep fuel from flowing.

__________________
RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Ok. Thanks about the air bubble. No "whoosh" when cap removed. I'll check these suggestions out and come back with results later.
Thanks again.

maybe some gunk in the lines that made it through when you changed the filters

Time for a biocide treatment. If you have enough water in the fuel to cause trouble it will just stop, I think. The water and diesel don't mix so the water lies on the bottom of the tank and when there is enough to be picked up you are out of business.

Don't ask how I know.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.