Author Topic: FI Pump Rack access  (Read 5183 times)

W14

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FI Pump Rack access
« on: May 11, 2003, 00:02:10 »
Hi All,

I would like to remove the plug at the front of the FI pump so I can check the rack movement.  I tried to remove the "flush" screw, but it's real tight. I just want to verify which is the correct plug (in the picture) to remove.
Thanks,


Download Attachment: F.I Pump front.JPG
56.76 KB

Will W14
1965 230SL 4spd
Victoria,BC

ja17

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Re: FI Pump Rack access
« Reply #1 on: May 11, 2003, 06:56:20 »
Hi Will,
The rack is behind that 10mm bolt and cap just below and inside! Later fuel injection pumps just have a rubber cover instead of this 10mm arrangement. Running engines usually do not have stuck racks. Lengthy damp storage or open dissassembled engines can get stuck racks. It does not hurt to check however since it is not difficult. This is a 230-SL and notice the small metal oil feed line in the background. Cees, this is a nice photo for the file!

Joe Alexander
Blacklick, Ohio
« Last Edit: May 11, 2003, 07:00:24 by ja17 »
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

W14

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Re: FI Pump Rack access
« Reply #2 on: May 11, 2003, 10:59:23 »
Thanks Joe,
My rack is not stuck, but the movement is not as smooth as it should be.  When I get the engine running again, I might want to do that mixture test as well, where you move the rack with the temporary bolt.
Here is a better pic. of the actual oil line:


Download Attachment: FI Pump Oil Line.JPG
62.35 KB

Will W14
1965 230SL 4spd
Victoria,BC

ja17

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  • USA, OH, Blacklick
  • Posts: 7414
Re: FI Pump Rack access
« Reply #3 on: May 11, 2003, 22:24:29 »
Hello Will, when you get it running, loosen one injector line at a time. If one is not pumping fuel, then a piston will be stuck in the pump. This is what causes the rack to be stuck or uneven. If you have the injection pump off the car, you can take the side cover off the pump and you can see all the pistons operate if they are free. Check back if you find any problems.

Joe Alexander
Blacklick, Ohio
« Last Edit: May 11, 2003, 22:26:51 by ja17 »
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

W14

  • Guest
Re: FI Pump Rack access
« Reply #4 on: May 11, 2003, 23:14:59 »
Hi Joe,
I removed the front plug and screwed a bolt into the front of the rack.  I also removed the cold start mixture solenoid, so I can now simultaneously push and pull on the rack. It is very stiff.  I also removed the side cover - it's all nice and clean in there, but I sprayed some WD-40 in anyways.  It had no effect on the stiffness of the rack.
On the one hand, the engine ran fine when I started pulling the car apart a year ago; on the other hand, now is a convenient time to pull the pump off the engine to see if I can free the rack some more....
If I turn the engine over with the starter, without a fuel supply, should I be able to see the pistons moving through the side cover opening?
Thanks,

Will W14
1965 230SL 4spd
Victoria,BC