Author Topic: Great Fuel Pump Price!  (Read 22852 times)

George Des

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Re: Great Fuel Pump Price!
« Reply #25 on: February 04, 2014, 14:12:20 »
Micheal, another reason for not replacing the cages is when a conversion is done from long pump to short. The long pump cage will not workwitb te short pump unless it is cut to allow passage of the hoses which are located differently between the two pumps.

ja17

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Re: Great Fuel Pump Price!
« Reply #26 on: February 04, 2014, 14:43:14 »
Picky, picky, picky. That's the trouble, once you get educated you all become critics !  :D

Naturally it is best to go factory original on the fuel pump, the fuel lines, wiring clamps etc. etc.

You can say this Carter installation was for "demonstration purposes only" or for the "photo shoot" or for the emergency "roadside installation".  Once the mounting, wiring and plumbing were worked out and finalized, the correct hoses were installed, a rubber boot was used to cover the wire terminals and the metal fuel pump cover was installed.  ;)

Yes Walter, only correct rubber fuel lines should be used for fuel. In this case they need to be rated for gasoline at 60 PSI  or more on the pressure side. The feed side to the pump can be the standard 30 PSI fuel line since it is under no pressure. Never use a hose rated for coolant for fuel, it will start swelling and degrading almost immediately.  

I have seen new old stock factory fuel lines fail before their time as new fuel formulations quickly degrade some old rubber fuel lines. Use newer inventories on fuel lines.
« Last Edit: February 04, 2014, 14:52:18 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

mdsalemi

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Re: Great Fuel Pump Price!
« Reply #27 on: February 04, 2014, 17:06:04 »
...another reason for not replacing the cages is when a conversion is done from long pump to short...

Yes, which is why I had to buy one at the screamingly outrageous price of $120 about 12 years ago. Today, I think many would be happy to find a cage at that price!

But it's all about the details…if you are or were replacing the fuel pump as noted, even 25 years ago, the right thing to do would be to replace the pump AND the cage. Many chose to leave it off, and that will surely shorten the life of the pump, or at least the wiring.

Of course, Joe, it is better to go with the original. But I think that too many people who struggle with this car just can't afford a $600 fuel pump, on top of all the other parts they have to buy during an R&R. My story about the Mini was replacing a junky quality (sorry my British friends) SU pump with a better American pump. I don't think you'll get a better pump that the Bosch for our car. It's expensive, that's all.

Yes, and those fuel lines…degrading over shorter and shorter amounts of time!
Michael Salemi
Davidson, North Carolina (Charlotte Area) USA
1969 280SL (USA-Spec)
Signal Red 568G w/Black Leather (Restored)
2023 Ford Maverick Lariat Hybrid "Area 51"
2023 Ford Escape Hybrid
2024 Ford Mustang Mach Ex PEV

Shvegel

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Re: Great Fuel Pump Price!
« Reply #28 on: February 04, 2014, 20:23:59 »
  If you look at our fuel systems in relation to hard warm starting you will see that the system relies on the check valves in the pump outlets and the injectors to keep the fuel lines pressurized and to prevent vapor lock. Any leaks at all and the lines loose pressure and the fuel boils in the lines.  What I did years ago was borrow some lessons learned from Bosches later systems.  I fitted a later pump from a CIS car and a pressure regulator from a Saab at the outlet of the pump that uses the diaphragm of the regulator as a reservoir to keep pressure on the fuel lines even if the pump check valves or injectors leaked.  Simple fix but it worked like a charm.

George Des

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Re: Great Fuel Pump Price!
« Reply #29 on: February 05, 2014, 01:18:24 »
Sounds like the later Pagodas have had real issues with vapor lock. I have never had any of these issurs with my 230Sl. Could it be that the newer FI pumps are the source of this?

ja17

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Re: Great Fuel Pump Price!
« Reply #30 on: February 05, 2014, 01:19:10 »
Now if the  non-original Carter fuel pump scares you take a look at this installation.  I removed these cheap $30.00 fuel pumps on two
W113 cars so far. These pumps should never be used. They are for carbureted  engines. The volume is very low, and maximum pressure is only 9 PSI .  The cars actually ran and drove for a while.  All kinds of starting and hot running problems resulted. One car even had a rebuilt engine, but was never able to run correctly until the junk fuel pump was replaced. All the mysterious running problems went away when the correct fuel  pumps were installed.
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

ja17

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Re: Great Fuel Pump Price!
« Reply #31 on: February 05, 2014, 01:37:48 »
Hello George,

Actually vapor lock is not model specific and is not normally a problem.  Hotter than normal engine operation and poor fuel circulation can cause some vapor lock problems in these cars.  A hard starting hot engine is one of the problems that shows up first.
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

garymand

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Re: Great Fuel Pump Price!
« Reply #32 on: February 07, 2014, 18:11:07 »
Never heard of a valor lock issue in 250 or 280's.  The fuel is under too much pressure to vaporize in a normally operating system.  One of the pleasures of my W113 ownership is the motor starting with only a turn or 2 of the starter.  When it doesn't I know I miss adjusted something or a part has failed.
Gary
Early 250SL German version owned since 71, C320, R350, 89 Porsche 944 Turbo S

m300cab

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Re: Great Fuel Pump Price!
« Reply #33 on: February 07, 2014, 22:17:15 »
I used a 450SL pump once
a guy did not want to spend the money
Michael Parlato