# 1998 DT530 Fuel Issue



## NicksTree (Jan 27, 2016)

My Dt530E has recently been losing its fuel prime for no apparent reason while in normal operation. The issue was easily corrected by simply pumping the primer and restarting the engine. The issue however has now become much greater. The truck will now lose its prime while the engine is off. Now when I get it to fire back up it is as if it is not running on all cylinders, very ruff and no power. I compare the symptoms to having a clogged up fuel filter. Steps I have taken with no improved results are as follows:
1) changed fuel filter, cleaned out strainer, checked ball above strainer 
2) eliminated coupling at back of engine which connected the feed line from tank to filter. It now has a direct line to the filter. Also eliminated down tube in tank with no positive results.
3) replaced primer pump. Resulting in the primer pump now being able to become hard. Original primer pump never got hard. Engine still runs horrible though.
4) replaced inline lifter pump and gasket which is mounted on the side of the HPOP. No difference, wasted $400.00.

All information, is great information. Thank you.


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## johnhenry1933 (Feb 11, 2013)

Sounds like a bad pump or contaminated fuel. 

1: Have you checked the bottom of the tank for sludge?:
2: I would then check for fuel flow through each line progressively front to back.


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## NicksTree (Jan 27, 2016)

Ok. Thank you I will give those a try.


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## johnhenry1933 (Feb 11, 2013)

You're welcome Nick, And welcome to the forum!

In a word, I suspect the fuel delivery. The easiest checks are what I described. Without giving a plethora of other checks, you may need to check the pressure, before and after the rail. And then, what color is your fuel? Also, you replaced parts of the fuel delivery system, and that may have been needed, but checking fuel pressure (with a gauge ideally, or manually as I described) will quickly detect either a clog, or a bad pump.

Finally, you gave no history of the engine. HEUI engines require regular oil change intervals. I have several of them and I change the oil faithfully. If not changed, a whole host of issues can otherwise unnecessarily be introduced.


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## Randall Ave (Oct 29, 2014)

Take it to a shop with IH software and run codes and texts. Is it loosing prime or running poorly? What color smoke?


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## bob00 (Sep 8, 2009)

check coolent for fuel contamination i know dt530 are big brother of the dt466 i am not sure if they had the same bras injector cup that fail and send fuel pressure to coolent so your loosing prime and have fuel in coolent


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