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+--- Thread: Fuel pressure testing (/showthread.php?tid=6303)
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Fuel pressure testing - Mrkentee - 06-19-2020
[attachment=6694]May be a dumb question, but...
There are two sets of specifications. One for WITH EGR. The other WITHOUT EGR. If someone has an 871 where egr is just for looks, which specs do they use?
RE: Fuel pressure testing - Lonestar10 - 06-19-2020
275-300 on 871
RE: Fuel pressure testing - Mrkentee - 06-19-2020
(06-19-2020 )Lonestar10 Wrote: 275-300 on 871
Mine is at the low end of that. But it stops at 1900 rpm. I don’t know if that would matter. I could raise that, but I didn’t.
RE: Fuel pressure testing - Lonestar10 - 06-19-2020
my 871 ran in the low mid 280s at full chooch.
RE: Fuel pressure testing - Mrkentee - 06-20-2020
The test says 2100 rpm. I guess mine is governed at 1900. Would the extra 200 rpm bring the pressure up a noticeable amount? It was right about at the low end of the spec. The needle was jumping a bit.
RE: Fuel pressure testing - Lonestar10 - 06-21-2020
If needles bouncing a bunch you might be getting a small amount of air in system
RE: Fuel pressure testing - Mrkentee - 06-22-2020
Fuel pressure test gauge fluttering.
Steady 22-24 psi with lift pump.
I isolated each tank by closing the valve on top-no difference.
Is this the pump? It has 1,080,000 miles. How long are these expected to last? And what about the shut-off valve?
Truck seems to run fine.
https://youtu.be/5r60FFOHs7I
RE: Fuel pressure testing - Signature620 - 06-22-2020
If the pressure is within specs and it starts/runs fine then the gear pump is OK.
What problem are you trying to solve here?
RE: Fuel pressure testing - Mrkentee - 06-23-2020
(06-22-2020 )Signature620 Wrote: If the pressure is within specs and it starts/runs fine then the gear pump is OK.
What problem are you trying to solve here?
I had 3 momentary low pressure cel’s at very low speeds about 100 hours apart. I replaced the fuel pressure sensor. Last week I had 2 momentary pressure differential cel’s in the same day.
Haven’t had any since. Just trying to find a problem before I get stuck somewhere. Thinking maybe pump is acting up. Possibly pressure regulators, or shut off valve??