Electric Lift Pump

[BrianX128]

I've been reading old threads as I'm thinking of going to an electric fuel pump. I can't find any threads with an active link to the correct facet pump that is always referred to to actually buy one. Maybe I'm just looking at the wrong threads. Also I know I'll need that block off plate.

Is there any benefit to running an style connections before and after the pump to the filter or just use rubber hose? Seems like the rubber hose and those tapered connections could come loose.

I know this isn't an overly complicated modification but I'm trying to make sure I have everything in order before I attempt it.

My summit electric fuel pressure gauge went down to 1.5-1 psi under full throttle going 70 in the mountains today. Usually it stays at 3 psi and at worst goes to 2 going up a hill but I think my old diaphragm pump is on the way out.

Any help in making sure I order the right stuff would be greatly appreciated.

 

[Macrobb]

Just swap in a new mechanical pump. It'll do just fine, be a lot cheaper, and probably last just as long as an electric pump.

Mine(unknown age) averages 4-5 at idle, 3 at WOT... with a 110 CC pump on it!

 

[mackmack]

I have a facet dura lift pump on my f350 and I love it . It is a lot more expensive than a mechanical one but it's worth it. Part number on mine is fac-40290 . Look up pegasus auto on the Internet that where I found mine.

Sent from my SM-G530T using Tapatalk

 

[BrianX128]

Awesome. I got the pump and block off plate ordered now. Only thing left is fittings and hoses.

I have a jegs gift card, question, is this hose ok for diesel use? http://www.jegs.com/i/JEGS-Performance-Products/555/15997/10002/-1

Then I'll just need to get some barbed fittings for threading into the pump and on the fuel filter housing.

Also, I couldn't tell from the tech article but how do you best connect the inlet side of fuel line going into the electric pump to the line coming from the tanks? Isn't it already rubber?

 

[sjwelds]

Make sure that the block off plate doesn'tcatch on the lip of the block, and cause an oil leak.

 

[shawn deere]

Awesome. I got the pump and block off plate ordered now. Only thing left is fittings and hoses.

I have a jegs gift card, question, is this hose ok for diesel use? http://www.jegs.com/i/JEGS-Performance-Products/555/15997/10002/-1

Then I'll just need to get some barbed fittings for threading into the pump and on the fuel filter housing.

Also, I couldn't tell from the tech article but how do you best connect the inlet side of fuel line going into the electric pump to the line coming from the tanks? Isn't it already rubber?[/QUOTE
Mine was a hard plastic
I just put a rubber hose on it with like 3 clamps, lol
I went with a holly red on the frame rail.
Its loud. Really loud.
Then i ran a new rubber hose clear into the filter head which was regular pipe thread.

 

[BrianX128]

So, I may have learned something today. On my way home from up in the mountains I noticed my fuel pressure was back to 3psi non stop.

I was wayyyyy up in the mountains in central pa when I was noticing the lower pressure readings. I'm thinking that the higher elevation was causing me to use way more fuel climbing these long steep grades at 65-70 mph. The truck was smoking a ton more then normal as well.

Then I'm driving home tonight and I tried flooring it on a similar long hill at lower elevation and was going 75 and couldn't get the fuel gauge to read under 2.5 psi even then. All smoking totally back to normal.

I still want to put the electric pump on [and I had already ordered it today] but I'm curious if this could effect it like I'm thinking. My fuel pressure gauge is also electric and I know those can be sensitive sometimes but it was a pretty expensive gauge from summit with great reviews so I think I'm right in trusting it's readings.

 

[gandalf]

At the higher elevation you had a richer fuel mixture because there was less air. The air was thinner, so you weren't getting as much air for the same amount of fuel. A richer mixture produces more visible exhaust.

I'll let somebody else answer about the fuel pressure difference.

 

[Macrobb]

At the higher elevation you had a richer fuel mixture because there was less air. The air was thinner, so you weren't getting as much air for the same amount of fuel. A richer mixture produces more visible exhaust.

Yup... Up high(without a turbo anyway), you lose power because of the lack of air. A NA IDI is already limited by air more than anything else.

I'll let somebody else answer about the fuel pressure difference.

I've thought about this for quite a while and I think I have an idea:
Our mechanical fuel pumps are a diaphragm pump. The cam actuates the lever, a spring returns it.
IIRC, when the cam pushes the lever, that's the "pull" stroke which pulls fuel from the tank.
The spring "pushes" the fuel into the IP.

Now, that pump is set for a certain PSI output. How? By sizing the spring to a certain amount of force.
The spring, I believe, is on the top of the lift pump, and is not in the fuel - it's got atmospheric air to that side of the diaphragm.

Air pressure will push against any surface evenly - at sea level, it's 14.7 lbs, IIRC.
Now, as you go up in altitude, that pressure drops. At 2,000 ft, you are at 13.7lbs or so.
The higher you go, the more the pressure drops.

Now, you have a diaphragm. The spring is exerting a force on it, and the atmospheric air is also exerting force on it, on the same side.
Normally, it's not a problem - the spring is calibrated expecting the 14.7lbs of force on it.

Now, you go way up in the mountains. The air pressure drops. The spring now has to work harder to force that diaphragm back, and because of that it loses just a little output pressure.


---
That's just my theory. Could be completely off, but this seems to make some sense.

 

[crash-harris]

You'll most likely need to retime the IP after installing the electric lift pump. More fuel pressure will advance the timing in the IP. I think I picked up the 40222 pump and it'll push about 7-8 psi at idle and 4-6 psi cruising, depending on grade and circumstance.

 

[BrianX128]

My timing could use a slight advance anyways so that might be an added benefit to doing this as well ha.

So the block off plate that's listed in the tech articles, does it fit pretty flush then or not? The article didn't say anything about it catching on the block like earlier mentioned.

Also, are the barb push fittings the best way to go for connections? I won't be doing this until next weekend when I'm off so I got time to make sure I'm getting everything in order first [for once]..

 

[crash-harris]

The block of plate mentioned in the tech articles is a perfect fit. You can check out the thread linked in my signature for how to do the fuel lines. The diesel approved hose and brass barb fittings eliminate a few air intrusion points and an olive seal at the filter head. Make sure you use injection line clamps for a total seal, not worm drive clamps.

 

[BrianX128]

Cool makes more sense now after seeing your pic of how you attached the hose coming from the tanks.

The thread at the fuel filter hard line is 1/8 right? Ordering fittings at work and didn't drive it today. The connections on the pump are 1/8 I know that.

 

[crash-harris]

Honestly, I cannot recall at the moment. If the size isn't in my thread, then I must've made a seperate thread inquiring about it. If the fitting on the input side is visually the same size as the aux ports (schrader valve, return line firing, etc.), then yes, 1/8" NPT.

 

[Macrobb]

You'll most likely need to retime the IP after installing the electric lift pump. More fuel pressure will advance the timing in the IP. I think I picked up the 40222 pump and it'll push about 7-8 psi at idle and 4-6 psi cruising, depending on grade and circumstance.

My timing could use a slight advance anyways so that might be an added benefit to doing this as well ha.

Just remember that it may make your timing a little more wacky than normal. I would expect that it will end up more advanced at idle, and then ending up more retarded at WOT.
You may still need to advance it to get the most power out of the truck, then have it really clattery at idle.

That is one reason I'm not particularly in favor of electric pumps - for a DB2, exact pressure doesn't really matter - it's easy to compensate for.
Relative pressure will mess with timing though, so you want a pump which will stay as close to X PSI from idle to WOT.