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Bought a 82 380 sl. It starts and drives about 2 miles then starts sputtering and can barely keep it running. PO said he just replaced the fuel pump and filter. Looked under and found what seems to be a correct pump with the blue ring. Looks to be new. I checked fuel pressure at the motor and its at 100? Is the pressure regulator or accumulator or the return line clogged?

Hoping someone else can help. I have read a ton of threads but everything not pertinent to my condition.

Also the oil pressure is fine and I always let it warm up before driving so I dont believe it is a cold start or warm up problem.
 

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1986 560SL with M120 V12 Engine, 1988 560SL Stock
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The pressure should be around 80. If you have the old iron fuel distributor you pressure regulator is adjustable by adding washers to the cap. Also higher pressure = less fuel.
 

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Discussion Starter #4
fuel pressure not rising. Pegged at 100. Is the cast iron regulator on the front of the motor? I followed the return line from the injectors to this part. There also is a line coming off that is not connected to anything. looks like a vaccuum line. Is this where I can regulate pressure or is that in the rear? I havent had a chance to get a manual yet.
 

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1981 380SL
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First things first. Get a manual. You have to have it. I think there is an online version over on EGV107. It will have specs for main system fuel pressure and control pressure for your year.

Also, get (or construct) a K-Jet fuel pressure tester. You need to be looking at main system pressure and control pressure. I bought mine (pro quality) for about $100. Well worth it, especially if it keeps hacks from messing with your car while charging multiple thousands. Of course, I had to learn the hard way.

Main system fuel pressure (which I think is what you measured, but not sure) is still adjusted on the 380 by shiming the fuel pressure spring in the distributor inlet with 4 cent metric washers. Super easy. The fuel inlet to the distributor is on the driver's side near the firewall.

Get the manual and proper diagnostic equipment and proceed.
 

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R/C107 Moderator
1986 560SL: '84 500SL: '84 280SL 5 speed: other 107s
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fuel pressure not rising. Pegged at 100. Is the cast iron regulator on the front of the motor? I followed the return line from the injectors to this part. There also is a line coming off that is not connected to anything. looks like a vaccuum line. Is this where I can regulate pressure or is that in the rear? I havent had a chance to get a manual yet.
Started over 90, then over 95, now pegged at 100.
Did you check the return line to the tank and in the tank to make sure it is not clogged as was suggested?

The part on the front right of the engine is the WUR and the disconnected fitting is a vent to atmosphere. The fuel dist. is on the left side of the engine.

http://www.benzworld.org/forums/r-c107-sl-slc-class/1450550-encyclopaedia-germanica-volume-107-aka-egv107.html
 
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