Author Topic: Exact fuel pressure test hookup help needed for a California 6.9  (Read 1015 times)

daantjie

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Re: Exact fuel pressure test hookup help needed for a California 6.9
« Reply #60 on: 16 September 2020, 07:48 PM »
I use NGK BP5ES on my 6.9, works great.
Daniel
1977 450 SEL 6.9 - Astralsilber

John Moore Sr

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Re: Exact fuel pressure test hookup help needed for a California 6.9
« Reply #61 on: 17 September 2020, 03:43 AM »
RE: Spark Plugs. In 1975  when 6.9s began rolling of the line, Euro market cars came out with Bosch W 200 T30 which was later renumbered W 6,  U.S. market  cars starting in 1977 used Bosch W 125 T30 which was later renumbered W 9 D, then to W 9 DC (copper core), then to 7511.  The 200 Euro plug has colder heat range for sustained high speed driving. The U.S. 125 plug (W 9 DC) has a hotter heat range for stop and go driving. W 9 DC plugs are pretty common on EBAY at various prices. For What It's Worth....JM Sr.                                         
1972 350SLC Euro Parts car, 1974 350SL Euro 3.5 V8 4 speed, 1978 450SLC Euro. 1979 6.9 #4630 1979 6.9 #7003 Parts Car, 1980 450SLC Parts car, 1985 380SL...and once had 1975 6.9 #142 until JuNIOR commandeered it.

ptashek

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Re: Exact fuel pressure test hookup help needed for a California 6.9
« Reply #62 on: 17 September 2020, 06:48 AM »
I think a lot of us here happily run the NGK BP5ES or BP6ES, depending if you want a colder/hotter plug.

If you go to the MB parts desk, you'll get a re-packaged Bosch plug. Either a W9 or a W8, can't remember which exactly.
1993 "Pearl Blue" W124 280TE
1988 "Arctic White" W124 200T
1979 "Icon Gold" W116 450SE (history, resto)

secondslc

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An update...

-New plugs in, no start. Bollocks

-Noticed the air meter plate was not moving when cranking. (I was a fool and adjusted it to have a bit of a gap before installing it.) Took it all apart and adjusted it per the manual. While I was in there I made sure the fuel mix screw was adjusted so that the 8 FD ports had fuel in them but would not move. Thats baseline. No start... damn

-Counted and cranked the screw in half a turn at a time as the plugs were dry. Turned it till the plugs were wet. No start.

Alright, so now I knew I was getting fuel, and I know the metering plate is moving when cranking. I also knew the timing was right and the entire ignition system was rebuilt...except the wires as I wanted to find the right ones... So I inspected and noticed the coil was warm...

Pulled the coil wire, adjusted the fitting. And here is the result.

https://youtu.be/OmSpmBpd3oM

;D

I adjusted the fuel to about a quarter turn past baseline and it no longer popped or missed. Seems to rev freely, and knowing what I know now... the fuel system is "perfect"

Next up
-An oil change as I have probably destroyed the oil in it.
-New ignition wire set
-I need to replace the rear leveling arm, as it broke during the fuel pump replacement, and I currently am set at full stiff, can't drive it.
-My cats smolder after a few minutes of running the engine above idle. The insulation starts smoking and well... it's a cause for concern as they cook the interior too. They're either clogged or extremely full of fuel. Either way, check out the awful mess coming out of my tailpipe.
-When I take the car in to inspect the cats...I am going to have two Wideband bungs welded in pre-cat so I can understand the tune. Seems like a much more reliable way of testing than an exhaust sniffer.

Then it's on to brake lines and tires. Aged rubber is going to be my next fun chase!

Guys, I was ready to give up on this thing, thanks for the encouragement, and convincing me I was so close. I'm still a ways from "finished", but at least the car feels alive.
1979 6.9
1983 urQuattro
1991 200 20V Avant
1993 Corrado SLC
1996 SL600
2009 Super V8

daantjie

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Niiiiice ;)
Daniel
1977 450 SEL 6.9 - Astralsilber

raueda1

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Awesome!  Persistence and patience paid off.  Looking forward to your next adventures.  Solid!
-Dave
Now:  '76 6.9 Euro
Before that:  1966 230S, 1964 220SE coupe, 1977 Carrera 3.0

rumb

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Glad to hear it is sorted now. Well done!
'68 250S, '77 6.9 euro, '91 300SE, '98 SL500 '14 CLS550