Why is my truck eating injector cup seals? - Diesel Forum - TheDieselStop.com
6.0L Power Stroke Engine and Drivetrain Discussion of the 6.0L Power Stroke diesel engine and drivetrain in the 2003-Up Super Duties and Excursions. No gas engine discussion allowed except on transmissions and drivetrain that pertain to all models. Please confine discussion of topics in this forum to those items that are specific to the 6.0L Power Stroke engine.

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post #1 of 3 (permalink) Old 05-17-2017, 01:15 PM Thread Starter
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Why is my truck eating injector cup seals?

So two years ago I fixed a hot start problem by changing the nipple cup seals and all the injector top seals.

They were pretty beat, but the big failure was the #6 injector seal. I also took out the HPOP and changed the STC o-ring at the same time (the STC was upgraded to the good kind before I bought the truck)

I figured I had it taken right care of because it has started and ran great for about 40k miles since then, with a good deal of idle time (service truck).

So a few weeks ago I developed a slow cold start issue, followed shortly by a slow hot start, and soon after that a slow cold start only and no hot start. Having been down this road before I knew what was likely broken, ICP pressure slow to build on cranking, but in spec when running.

I took a gamble on it and took off the drivers side oil rail today (hoping to be able to use it tomorrow for work) and found the #6 seal in rough shape, and the #4 seal a little beat up, they all seemed a bit stiff, even though I used Bosch seals the first time.

The nipple cups all appear to be in great shape still (viton gaskets) practically no movment on them, and no sign of oil spray or broken seals.

So what is causing the injector seals to get torn up in under 50k miles? Worn nipple cup? Worn injector cup or snap ring?

Anyone dealt with this as a chronic problem? It sprung up rather suddenly from delayed starts to no starts, but the hot weather keeping the oil warm probably doesn't help.

I will note that the first time I found no real problems on the passenger side other than stiff seals, so I'm going to just do this side for now and see what develops, hopefully the issue is resolved, at least for another 2 years.

1995 F-250
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post #2 of 3 (permalink) Old 05-19-2017, 11:22 AM
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A seal that has a sliver coming off of it is typically an installation error. Are you seating the oil rail fully prior to installing the bolts?
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'06 F250 4x4 - 5" Flo Pro exhaust, SB Filter intake, Accufab elbow, Edge Evolution (monitoring only), SCT w/ ID custom tune, FASS 195 pump, Gillette Diesel EGR cooler delete, Sinister Diesel coolant filter, ELC coolant, updated turbo drain tube/oil feed line/STC fitting/oil cooler, ARPs w/OEM HGs, Elite coolant lines, ITP RR fuel system, RCD 175/30 injectors, Powermax, BD CCV, FICM.com FICM w/ ID tune, Elite UP, BPD water pump - 13.069 @ 101.94

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post #3 of 3 (permalink) Old 05-21-2017, 07:48 AM
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Yes. Torn seals are only that way due to poor installation.

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