About three weeks ago I serviced my 2016 f350 6.7. It's currently got 11,500 miles on it .I changed oil and fuel filters. Went through the purge cycle truck primed up with no issues started and ran everything was fine. So today 300 miles later i ran an errand about twenty minuets away. The truck went into regen as I was pulling into the drive. Shut it down half an hour later started it. Pulled out on the road drove about 500 yards and got a reduced power warning and a low fuel pressure warning with an amber engine light on. The truck never missed it ran rough but power was indeed reduced for a while. The faults cleared and I got the truck home. Only thing I noticed is the fuel pump in the tank sounds noisy. No leaks i can see. Drained the water Sep no water or crud came out. Any ideas???

 

Did you tighten the bowl on the filter until it hit the stop?

 

Yes. I replaced the oring tightened the bowl until it but the stop. I'm gonna pull the bowl back off tonight

 

As Doug said. Check to make sure you got the filter cup tight and against the stop. Do not over tighten it.

If this doesn't solve the problem, drop the filter cup and make sure the o-ring isn't twisted or nicked. Lube the o-ring with some clean diesel or oil before installing the cup.

 

After all of that, the only other cheap thing I can think of is the o-ring on the drain ****. They have been known to get damaged when opening the drain valve too far, or allowing air in by not having the valve fully closed. You should see fuel leaking if that were the case though.

Do you use any fuel additives?

 

I'm going to let it sit in the shop tonight and dry off but I never saw any spots on the floor. It's pouring down rain here today. Ill pull the bowl off tomorrow. I do run Stanadyne performance formula (blue lable) in everything.
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If the cup is snug but not at the stop, it can suck air and never leak.

As mentioned, check the o-ring on the yellow drain valve. It sometimes gets stuck and comes off the ****.

I would suggest removing the cup and starting over with the install. I would clean the cup and check the yellow know o-ring. Check to make sure you didn't leave the old o-ring in the upper housing. Lube the cup o-ring. Install the cup till it stops at the stop. Prime the filter as you did before. Should start with no lose of power problems.

 

The reason for the question about using additives was because many additive bottles have a small cardboard disk that will stick to teh top of the bottle once the lid is removed, and is then unknowingly poured into the fuel tank with the additive. It is just the right size to plug off the fuel inlet in the tank.

 

Stanadyne uses a seal that you physically have to remove with the pull tab. You take off the cap, then pull the seal off before you can pour the contents into the tank. It doesn't have the small round disk that seems to affect some.

Check this article on the Ford Doctors DTS site (they are the writers of the coffee table books)

Fuel Additive Bottle Caps - DTS Articles - Diesel Technician Society

 

I never would have given that a thought about the cardboard thing in the cap. That couldn't really happen in my case though. I treat my bulk tank with Stanadyne and filter it to 20 micron before it ever makes it into my equipment.

Well I pulled the bowl off this morning. The oring on the bowl and the draincock were ok. I ran back to Napa ant they gave me a new primary filter and oring. I put it back together purged the air and she fired right up.

 

I see....not running OEM fuel filters...that is most likely the issue here. With this other filter, did you have to change the cap too?

 

I run Wix/Napa Gold filters on all my vehicles and equipment. Up until now I've never had an issue. No I didn't have to change anything. Just the filter and o ring. Everything went together like it should. The truck is bone stock with 11,500 miles on it