So ever since I had the drop in fuel pressure which I have not mechanically tested yet my fuel economy has steadily went down since then. Have not had the chance to hand calculate yet but lie o meter says it went from 16.8 to 14.3. I picked up a tester today so I’ll be able to rest idle pressure soon. Where do I hook up the tester? 

 

The pressure went went down and then back up to 17 18 at idle and 12 13 wot. 

 

Used to be 19 20 at idle and 15 16 wot before the drop. 

 

So I got to test idle pressure at the filter canister with a friends short hoses tester. It read same as the edge monitor. 17 18 psi idle. Revved to 1200 and had 15 16 psi. Seems like the edge is spot on so far. I do have the Vulcan diesel tester on the way to test wot pressures. Now I’m really stumped as to the cuase of the drop in psi... Maybe the pump is going bad slowly? I have heard of a ball

and spring hat is adjustable inside the ddrp should I try that?

My DDRP was losing pressure so I took it apart & stretched the spring a little bit.  I have great pressure now.  It's pretty easy to do just remove the aluminum plate & the ball & spring are right there.  Take notice if the ball is deformed at all as you might need a new one.  Take care of the O ring too. This could get you by until you upgrade.  

 

L8tr

d

38 minutes ago, SilverMoose said:

My DDRP was losing pressure so I took it apart & stretched the spring a little bit.  I have great pressure now.  It's pretty easy to do just remove the aluminum plate & the ball & spring are right there.  Take notice if the ball is deformed at all as you might need a new one.  Take care of the O ring too. This could get you by until you upgrade.  

 

L8tr

d

I believe I will try that Saturday along with the valve adjustment! Thanks 

I think the proper length of the spring is 5/8".  Google it and you will see a bunch of info on it.  

 

Here's my post about it

 

L8tr

d

56 minutes ago, SilverMoose said:

I think the proper length of the spring is 5/8".  Google it and you will see a bunch of info on it.  

 

Here's my post about it

 

L8tr

d

Obviously when I remove the lines from the lp fuel is gonna spill and likely run back in the hoses. Will it prime by itself when I’m done or will I need to bleed something?

I normally use a pair of vise grip needle nose pliers to clamp off the fuel lines to prevent a mess and losing prime.

21 minutes ago, Mopar1973Man said:

I normally use a pair of vise grip needle nose pliers to clamp off the fuel lines to prevent a mess and losing prime.

My pump to filter hose looks pretty worn and cracked. I’ll problably replace them Ll with a big line and banjo fitting kitnif the pump ends up being ok

Make sure you put something on the jaws of the vise grips so as to not damage the hose. I use squeeze clamps like you get at the lumber yard, they already have pads on them.

To prime I just open the water drain on the filter until fuel comes out.  You might have to run the starter for a short while but it works for me.  It's not too messy either.

 

L8tr

d

@SilverMoose how do I get this aluminum plate off??

Well guys apparently the lift pump has been replaced since the Fass was on there because this pump looks nothing like the other Ddrp pumps. There was a number on the outside that said e7153. I googled it and come too find out that it is a airtex lift pump!!! Now I’m not sure what to do! Has anyone had experience with these pumps? I defiantly think a new lift pump is in order.  

Here is a pic of this pump. 

Yeah that's parts store trash.  Not adjustable and not reliable.

1 hour ago, trreed said:

Yeah that's parts store trash.  Not adjustable and not reliable.

Ha I guess that’s my bad because maintenance records said it was a ddrp but I never looked very close at it.

Yes, that's an Airtex lift pump.  I have that parts store trash mounted as a back up pump to the Fuel Boss.  I've used it twice to prime the fuel system.  It was reliable enough for that.

  

Meant it wasn't reliable enough for sustained use as a primary pump...  

1 hour ago, trreed said:

Meant it wasn't reliable enough for sustained use as a primary pump...  

Next paycheck will get a dtt assasin on the way! 

I readjusted my valves yesterday and they were a little messed up so maybe his is my mpg thief? Doesn’t seem like it would take almost 4 mpg out. Next thing is going to be injectors. Thinking that that is going to fix the rest of mpg as these are original with 127k on them. How long have you guys went on original Bosch injectors?

Mine went +/- 175k before I went up in size.  I still have them and they had no issues when I pulled them that I am aware of anyway.  I didn't have them tested though. 

 

7 minutes ago, Gamble said:

Mine went +/- 175k before I went up in size.  I still have them and they had no issues when I pulled them that I am aware of anyway.  I didn't have them tested though. 

 

Hmm well I will prob be going with 7x0.010s later so I guess I’ll find out then! 

I m wondering if the winter weather and fuel didn’t have quite a bit to do with my loss. Still I think it’s something else too. How many mpgs have you guys lost in winter? It’s averaging about 20 degrees here right now 

Remember as cetane RISES the BTU's FALL! 

 

This is an ASTM testing label scale for cetane and BTUs. The Dark green is typical summer fuel where the light green is winterized fuel. These are not always exactly these number but it shows the relationship.

Point of Reference: Gasoline is just below the 120k BTU mark...

https://en.wikipedia.org/wiki/Gasoline_gallon_equivalent

 

Colder the air the steeper the timing curve. This can be harmful to MPG because the fact the ECM can measure temperature of everything but can't measure the cetane of the fuel so it could be slightly over timed. Hence this where my MPG fooler was created for. 

 

Then there is wind resistance difference. Colder the air is denser so you got to travel roughly 5-10 MPH slower to equal the same drag as summer time. 

 

Lube oils in the axles are going create some drag till warmed up. Being super cold like minus weather it might never really warm up much.