Are you reading your pressure, post or pre filter?

 

Pre-filter. The filter has 2,000 miles on it. Since the filter pushes the plunger in the stand pipe down, I would assume these pressures would be close to the same. This weekend I guess I'll move my sensor to the post filter hole and see if anything changes.

Of course even if it does, and the fuel pressure the injectors see are in the 60 something range, that doesn't change the fact that I've got high pressure in the bowl and seem to be having a rather bad stretch of luck with fuel pumps.

 

Haven't had a chance to play with it yet. Had to go pick up 12,000 lbs of gravel this morning in a trailer that weighs 10,000 empty. It was kinda on the heavy side.

I have noticed that on cold mornings (50's) my fuel pressure is around 75 psi, but after the engine warms up it goes back to the 82 - 85 psi range. I'm not sure what to make of this. Something swelling with a warm engine and restricting the return to increase pressure? It would have to be at or near the FPR for engine temps to affect it. It's not the poppet seat since I've got the old poppet seat that's kind of smashed flat on the old plunger in there now. There was no change between old and new.

 

Chris,

I think your truck is on it's last leg and you should break down and buy a 6.7. I'll be a nice guy and give you $1000. I'll probably just replace the fuel bowl...lol. jk...idk..

 

Chris If you do a full blown Reg Return let me know,I almost have enough parts left over to do another one.I'll make you a good deal on parts.

I have all 3/8" line form tank to engine and stock pump running 68psi with no prob.

 

I've been thinking about it. Problem is I can't do just one. If I do mine, I'll have to do hers too. Or maybe I just put one on hers and steal her fuel bowl.

 

Sounds like a plan! Get to it!

 

I'd kind of like to know what is causing the problem though.

 

I know you do! I'd send you my old fuel bowl to try, if I hadn't already given it away.

 

This guy is selling a fuel bowl for $30. Seems like a good deal.

https://www.ford-trucks.com/forums/1...-for-sale.html

 

Nice find. I'll give the semi-local guy a chance to match the price. I finally got around to changing that last piece and move the sensor to the post filter position. It did feel like it fit in there better, and it dropped about 2 psi, but not that much of a help. I'll try a new bowl next.

If I end up building a regulated return, where do I get the regulator? What's the best one to use?

 

Aeromotive and Fuel Labs are some that are used in the Regulated Return kits. I have the Aeromotive #13109, which has #6 ORB ports for supply and return. I purchased mine (along with the bracket, misc fittings, and hose) from another member before he sold his truck. You can find them on Ebay; or get one from Summit Racing or Jegs.

 

Did you figure out anything on this?

 

I figured a few things out. Most importantly, if you cut down the spring, you need to file the cut end so it doesn't get hung up on the side of the plunger and give you high readings. I also found out that I have higher fuel pressure with cold fuel than when the fuel warms up.

I trimmed a spring so the fuel pressure was 70 psi with the key on, cold. That turned out to about 64 psi at idle with warm fuel, 60 running down the road and dropping down to 55 under acceleration empty, 49 under heavy acceleration with a loaded trailer.

I plan on watching it for a week or so and seeing if anything changes. I think the spring I've got in there now is too short and cannot hold the pressure under load. I'll put a little bit longer spring in there after a week or so. Meanwhile I'm still considering the regulated return with a real regulator.

 

Good deal Chris. Glad you got it figured out!