Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 08-31-2011, 06:14 PM
elchivito's Avatar
ĦAy Jodido!
 
Join Date: Aug 2009
Location: Rancho Disparates
Posts: 4,075
Is this terminology correct?

Lift Pump = Injection Pump?

__________________
You're a daisy if you do.
__________________________________
84 Euro 240D 4spd. 220.5k sold
04 Honda Element AWD
1985 F150 XLT 4x4, 351W with 270k miles, hay hauler
1997 Suzuki Sidekick 4x4
1993 Toyota 4wd Pickup 226K and counting
Reply With Quote
  #2  
Old 08-31-2011, 06:33 PM
Registered User
 
Join Date: Aug 2011
Posts: 33
The lift pump is what sucks the fuel from your tank and feeds the injection pump at about 8psi.

The injection pump takes that constant 8psi and basically has a plunger for every cylinder that takes your 8psi and makes it about 1200psi at the perfect time.
__________________
Jesse.
'80 300sd modded everything begging for more fuel.
'98 f-250 psd, d60 elocker front, intake, exhaust, dp tuner F5 etc..
'70 f-250
'83 242 Volvo project
'66 volvo amazon
'10 fuso FE-180 service truck, welder, compressor, 3500lb crane, oil tanks, etc...
Reply With Quote
  #3  
Old 08-31-2011, 06:33 PM
Banned
 
Join Date: May 2002
Location: Blue Point, NY
Posts: 25,396
The "lift pump" provides fuel to the injection pump. It's a bit of a misnomer..........."fuel pump" would be a better choice.

The injection pump cannot draw its own fuel..........fuel must be provided to it under pressure.
Reply With Quote
  #4  
Old 08-31-2011, 08:30 PM
Diesel911's Avatar
Registered User
 
Join Date: Sep 2007
Location: Long Beach,CA
Posts: 51,042
X2 on the above. I have been trying to write like this; Fuel Supply/Lift Pump when there is more than one common name for things.
Also most of the Mercedes Diesels; so far; in the threads do not have Fuel Injection Systems classified as Common Rail Fuel Injection Systems (what supplies the high pressure for Injection is different on a Common Rail Fuel Injection System).

To add to the confusiong some Fuel Injection Pumps have the Fuel Supply/Lift Pump built inside of them. Examples are the VW Rabbit and the Standyne Fuel Fuel Injection Pumps used by Gm, Chevy, and For.

My Volvo Diesel has a Fue Injection Pump Similar to the VW Rabbit. It has a Vane type Fuel Supply/Lift Pump built into the Rear of it inside of the Pump Housing. There is no other Pump to bring the Fuel from the Fuel Tank.
__________________
84 300D, 82 Volvo 244Gl Diesel
Reply With Quote
  #5  
Old 09-01-2011, 08:23 AM
elchivito's Avatar
ĦAy Jodido!
 
Join Date: Aug 2009
Location: Rancho Disparates
Posts: 4,075
Lift pump = fuel pump. Got it , thanks!
__________________
You're a daisy if you do.
__________________________________
84 Euro 240D 4spd. 220.5k sold
04 Honda Element AWD
1985 F150 XLT 4x4, 351W with 270k miles, hay hauler
1997 Suzuki Sidekick 4x4
1993 Toyota 4wd Pickup 226K and counting
Reply With Quote
  #6  
Old 09-01-2011, 10:57 AM
Registered User
 
Join Date: Sep 2004
Posts: 8,971
Quote:
Originally Posted by Dieselboy740 View Post
The injection pump takes that constant 8psi and basically has a plunger for every cylinder that takes your 8psi and makes it about 1200psi at the perfect time.
Just how impressed is a 115 bar injector going to be with 1200 psi fuel pressure?
Reply With Quote
  #7  
Old 09-01-2011, 12:12 PM
Registered User
 
Join Date: Aug 2011
Posts: 33
Quote:
Originally Posted by tangofox007 View Post
Just how impressed is a 115 bar injector going to be with 1200 psi fuel pressure?
It was to simplify things and at that time the exact pressure escaped my mind in a puff of cerebral flatulence. I guess I should had of said about 1669.7psi. Still made sense though of the difference between the two.
__________________
Jesse.
'80 300sd modded everything begging for more fuel.
'98 f-250 psd, d60 elocker front, intake, exhaust, dp tuner F5 etc..
'70 f-250
'83 242 Volvo project
'66 volvo amazon
'10 fuso FE-180 service truck, welder, compressor, 3500lb crane, oil tanks, etc...
Reply With Quote
  #8  
Old 09-01-2011, 02:12 PM
vstech's Avatar
DD MOD, HVAC,MCP,Mac,GMAC
 
Join Date: Mar 2006
Location: Mount Holly, NC
Posts: 26,835
Quote:
Originally Posted by Diesel911 View Post
To add to the confusiong some Fuel Injection Pumps have the Fuel Supply/Lift Pump built inside of them. Examples are the VW Rabbit and the Standyne Fuel Fuel Injection Pumps used by Gm, Chevy, and For.
I thought the GM's had either a manual lift pump driven off the cam, or an electric pump in the fuel line from the tank...
I KNOW my 92 has an electric lift pump and there is a stinking oil pressure switch that goes bad killing the power to the pump sometimes... arrgh!
__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!
Reply With Quote
  #9  
Old 09-01-2011, 02:35 PM
sixto's Avatar
smoke gets in your eyes
 
Join Date: Jun 2000
Location: Eastern TN
Posts: 20,841
My 97 6.5 has an electric pump feeding the lift pump. When the alternator died, I pushed on until the headlights were candles. I don't know if the electric pump was doing anything but the engine was fine. I read running off the lift pump alone can damage it or the IP.

Sixto
87 300D
97 C2500 'burb 6.5
Reply With Quote
  #10  
Old 09-01-2011, 04:42 PM
Registered User
 
Join Date: Aug 2011
Posts: 33
My 7.3 idi has a mechanical lift pump to supply the db2. My obs powerstroke has a mechanical pump too. (for now)

I put a holley red fuel pump on my 7.3idi a few years ago and after a year I was having trouble starting it. Come to find out the cheap pump was sucking air when it was off all the screws that held it together were loose and the rubber was mush.
__________________
Jesse.
'80 300sd modded everything begging for more fuel.
'98 f-250 psd, d60 elocker front, intake, exhaust, dp tuner F5 etc..
'70 f-250
'83 242 Volvo project
'66 volvo amazon
'10 fuso FE-180 service truck, welder, compressor, 3500lb crane, oil tanks, etc...
Reply With Quote
  #11  
Old 09-01-2011, 05:15 PM
Diesel911's Avatar
Registered User
 
Join Date: Sep 2007
Location: Long Beach,CA
Posts: 51,042
Quote:
Originally Posted by vstech View Post
I thought the GM's had either a manual lift pump driven off the cam, or an electric pump in the fuel line from the tank...
I KNOW my 92 has an electric lift pump and there is a stinking oil pressure switch that goes bad killing the power to the pump sometimes... arrgh!
Yes, my memory lapsed a little. Back when I worked on them they had Diaphragm Lift Pumps.
However, the Stanadyne Fuel Injection Pump still has a Fuel Supply/Lift Pump
Below is what you are speaking of and Transfer Pump is yet another name used for Lift Pump.

"Fuel is drawn from the fuel tank by a mechanical lift pump that is completely independent of the DB2 injection pump, and passes through filters and into the injection pump inlet. From there, fuel flows past the inlet filter screen to the vane-operated transfer pump located in the DB2 pump end cap. The vane-type transfer pump consists of a stationary liner and spring-loaded blades carried in slots at the rear of the transfer pump rotor. As the blades rotate in the liner, they move outward and the volume increases until the leading blade passes out of registry through the inlet slot. The fuel between the blade is carried to the bottom of the transfer pump liner and enters the outlet groove. As a result, pressurized fuel is delivered through the pump into a channel to the hydraulic head
passage."
The above in blue is what I was trying to seak of.
The above is from the below Link.
http://www.dieselpowermag.com/tech/general/0809dp_stanadyne_db2_injection_pump/viewall.html

The Stansdyne DB and DB2 Fuel Injections Pumps are used on other Engines and they may or may not have Lift Pump between the Fuel Tank and the Fuel Injection Pumps.
__________________
84 300D, 82 Volvo 244Gl Diesel
Reply With Quote
  #12  
Old 09-01-2011, 05:39 PM
Diesel911's Avatar
Registered User
 
Join Date: Sep 2007
Location: Long Beach,CA
Posts: 51,042
Quote:
Originally Posted by sixto View Post
My 97 6.5 has an electric pump feeding the lift pump. When the alternator died, I pushed on until the headlights were candles. I don't know if the electric pump was doing anything but the engine was fine. I read running off the lift pump alone can damage it or the IP.

Sixto
87 300D
97 C2500 'burb 6.5
I am not sure why that would happen.
The Lift Pump inside of the Fuel Injection pump in this case provides the pressure and volume needed to push the Plungers out (no springs).

The amount of Fuel Volume pushing the Plungers out determines how far out the Plungers go and the amount that is going to be Injected when the Plungers are pushed in (minus some leakage because the whole IP is lubed by the Diesel Fuel).
This means that if something interferes with the Lift Pump (inside of the IP) Fuel Volume or pressure it is going to effect the amount of Injected Fuel and you are going to notice that because your Engine is not going to run right.
the Lift Pump inside of the IP also provides the pressure to move the Advance Piston inside that advances the Injection Timing.

The only time I think it would be possible to damage the Fuel Injection pump in this case would be if the Lift Pump Inside of the IP was not getting enough Fuel during cranking and some one kept on cranking and cranking.

In the above case there would be no Fuel circulating through the IP to cool or lube it and because the Engine is not running yet you would not notice anything out of the ordinary.

__________________
84 300D, 82 Volvo 244Gl Diesel
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 01:17 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page