Pagoda SL Group

W113 Pagoda SL Group => Drive train, fuel, suspension, steering & brakes => Topic started by: DB280 on January 25, 2008, 09:55:32

Title: holley fuel pump 512-103 on a 68 280sl?
Post by: DB280 on January 25, 2008, 09:55:32
My bosch fuel pump(no 0 442 200 0 stamped on case) stopped working.I spoke to ray at bud benz and he sent me the seals etc for a rebuild.However when these arrived the seals and brushes were the wrong sizes so I am now considering a new pump.Ray suggested the HOLLEY mfg, pro-jection fuel pump. old # 512-103
new number being used  12-927 again Holley number.($145 on ebay)
This pump is much cheaper than a genuine Bosch one so will it fit and work correctly?

I would still consider rebuilding the old one if I could get the correct parts but I am $34 down at the moment and need to be certain any repair parts are right this time.Is the pump on my car the correct one?

Thank you
Garry
Title: Re: holley fuel pump 512-103 on a 68 280sl?
Post by: jeffc280sl on January 25, 2008, 11:15:35
The BBB says the pump needs to deliver 1 liter of fuel in 15 seconds.  Feed pressure is set at .8 to 1.1 atu which converts to 11.76 to 16.165 psi.

Can't speak about the connection and mounting issues.

Jeff C.
1970 280SL 4-speed
Title: Re: holley fuel pump 512-103 on a 68 280sl?
Post by: merrill on January 25, 2008, 12:10:20
there is a thread in a forum about rebuilding this pump or just
send it to Hans at H &R for rebuild

Matt
Austin Tx
66 230 sl - "white"
78 300 D - Blue
98 C230
Title: Re: holley fuel pump 512-103 on a 68 280sl?
Post by: George Des on January 25, 2008, 14:44:37
Based on the numbers you provided, you have the older, large style pump. MB does not have repair kits for these pumps. If you want to rebuild it, first verify the pump style you have and then send me an e-mail. I would not recommend going to an off brand fuel pump even though some have reportedly had some successes in doing so.

George Des
Title: Re: holley fuel pump 512-103 on a 68 280sl?
Post by: Peter van Es on January 25, 2008, 16:23:21
Please visit the Technical Manual, section on rebuilding Fuel Pumps. It answers all your needs.

Peter

1970 280SL. Also known as 'admin@sl113.org' and organiser of the Technical Manual (http://www.sl113.org/wiki/pmwiki.php).
Title: Re: holley fuel pump 512-103 on a 68 280sl?
Post by: ja17 on January 25, 2008, 17:30:53
Hello Garry,

The fuel system on the W113 cars is a continuous loop.  So any fuel pump used must deliver a larger volume of fuel than needed for most cars. The return line to the fuel tank on these cars is like a huge fuel leak. (back to the tank). While all this fuel is returning to the tank, the fuel pump must maintaine around 11 to 15 psi. fuelpressure to the engine. This is not high pressure, but is high volume. If you change to anything else you will need to check the pressure in the system and reduce it if it is too high.  If your volume is not high enough the fuel pressure will fall below the minimum during high fuel usage conditions and the engine will miss and buck.

The easiest retrofit is using the later Mercedes EFI electric fuel pump. It was used on the early 450SLs with EFI injection. These are smaller simpler, deliver correct volume and pressure. An aftermarket identical reproduction is made in Japan for less than $200.00 new. As with the original, these are gravity feed and must be mounted near level with the bottom of the fuel tank.

Some high volume racing pumps will work, some won't. Some of these are expensive also.

Joe Alexander
Blacklick, Ohio
Title: Re: holley fuel pump 512-103 on a 68 280sl?
Post by: Benz Dr. on January 25, 2008, 18:10:25
The EFI system runs at 30 PSI. You might have to throttle it down quite a bit.

Dan Caron's
 SL Barn
benzbarn@ebtech.net
 slbarn.mbz.org
  1 877 661 6061
Title: Re: holley fuel pump 512-103 on a 68 280sl?
Post by: rwmastel on January 25, 2008, 18:34:41
Garry,

George Des has been helping members here rebuild there fuel pumps.  You should contact him.

quote:
Originally posted by vanesp

Please visit the Technical Manual, section on rebuilding Fuel Pumps. It answers all your needs.
Technical Manual section on Fuel Pumps:
http://www.sl113.org/wiki/pmwiki.php?n=Fuel.Pump

Rodd
Pagoda Technical Manual
please contibute: http://www.sl113.org/wiki/pmwiki.php
1966 230SL
2006 C230 Sport Sedan
Title: Re: holley fuel pump 512-103 on a 68 280sl?
Post by: Blue 280sl on July 12, 2010, 14:45:24
Please send me some info on how to get in touch with Hans at H&R
Title: Re: holley fuel pump 512-103 on a 68 280sl?
Post by: Kevkeller on July 12, 2010, 17:56:00
Gary,

What parts are included in your rebuild kit.  I'll buy it from you if you want.  Email me at:

kevkeller@earthlink.net

Thanks,

Kevin
Title: Re: holley fuel pump 512-103 on a 68 280sl?
Post by: Nate on July 12, 2010, 18:06:16
Ask to speak with Hans:

http://longisland.citysearch.com/profile/7488036/bohemia_ny/h_r_fuel_injection_ltd.html
Title: Re: holley fuel pump 512-103 on a 68 280sl?
Post by: 66andBlue on July 12, 2010, 22:46:17
You can also find his phone right here on the web site - in the technical manual.  Your first stop for parts and service suppliers: http://www.sl113.org/wiki/Suppliers/Start
Scroll down to H&R Fuel Injection.