Hi all. I have a 71 280SL which I was driving home almost 2yrs ago when it just stalled out in front of my apartment complex. I pushed it into the garage and I have been unable to get it to run since then and now I'm at witts end. I have been back and forth on the pagoda forum which has been extremely helpful and through their expertise I have ruled out a lot of things. However, the problem persists and we have not been able to come up with a diagnosis. I'm hoping that someone here might have some insight.
Initially, I noticed that the fuel pump wasn't running, so I checked the fuse. It was burned out. I replaced it and the pump started working. I then checked the current draw at the fuel pump fuse terminals. It was drawing 3.2 amps which is within normal range. The car still would not start. I then checked the fuel pressure and volume. The pressure was 16 psi (normal) and the volume was 600-700cc/15 sec which is under the 1000cc required output. This should nevertheless be enough to get the car to idle and probably run just fine.
I then tackled the ignition system. I replaced points, condenser, cap, rotor, plugs, wires, coil, ballast resistors, set the dwell to 38 and the car started. It however would not run. The engine would run roughly for a few minutes, put out gray/white smoke (not vapor), backfire occasionally, and eventually stall once too much or too little throttle was given. The car has remained in ths condition ever since.
I then checked compression and all six cylinders were around 200 psi. 197-201.
I turned my attention back to the fuel system. I check the main fuel filter in the engine which was clean. I replaced it anyway. I checked the small filter screen in the electric fuel pump where the intake line from the tank hooks up. It was clean. I then peered into the tank from the top through the sender hole. The tank was clean with bright shiny metal surface on the inside. I also blew out the fuel return line where it originates from the injection pump. The line was clear. At this point I ruled out a fuel tank, fuel pump, fuel line issue. I checked the rack in the injection pump which moved freely and I checked the cold start valve which doesn't leak and sprays a nice mist when cranking the engine cold.
I messed around with the timing, turning the distributor from right to left but still no change.
I'm getting frustrated here. Everything checks out but the car still won't run properly. Any suggestions appreciated.
Check the inlet filter at the pump. I'm suprised the Pagoda group can't help you. Really, you need to check the basics, cap, rotor, wires, plugs, dwell. Once those are perfect, then go after other problems.
Once while driving my 230S from many years ago, it quit at an intersection. There was a parking lot across the street so I managed to get the car into the lot and do some checking. I found that the hold down screw for the points had stripped. I got home, via taxi, got a replacement from my spare engine and returned to the car. I replaced the screw and the car ran just fine, after I reset the gap. So, check the basics then go after the other problems.
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Near Manassas Va. '89 300SE, 2002 Ford Crown Victoria Police Interceptor, 89 420SEL
Had '65 220SE, 67 230S, 72 280SE 4.5 Dad had '65 300SE LWB, '65 220SE
"Of all tyrannies, a tyranny sincerely exercised for the good of its victims may be the most oppressive." C.S. Lewis
Basics is good.
I had van from another manufacturer from that era (carbys & points etc.) that had to be towed, all for the sake of a handful of loose or cracked vacuum lines. Refitted or replaced where necessary & again she purrs. Go the basics.
You will need to check for proper fuel presure at the supply (after the electric fuel pump) and on the return line as well. I do not know the exact values but these may be available in an old Motor Manual available at your local library. The fuel regulator can exhibit the symptoms you mention. If the regulator is not functioning properly there will be fuel starvation at the injection pump as the fuel improperly returns to the tank. Check for the vacuum line to the regulator or for leaks from the fuel regulator diaphram that will be evidenced by fuel in the vacuum side of the regulator.
Well, here's a new development. I checked timing yesterday with timing light and the light would only fire when the #1 wire was removed from plug and boot allowed to arc to head. I noticed the same phenomenon with cylinder #5. All the others were ok. This might be a plug problem even though the plugs were replaced when this all started.
Heres my take on this...check your spark by placing a spark plug in a plug lead and placing it on the head.
get someone to crank the engine and see if you have spark .even a tiny spark in the plug indicates that you have something.
BUT if nothing happens you start by checking all connections.
Start by removing the distributor cap.
ANY little cracks as indicated by tracking marks will stop the car starting.
Check the rotor for the same marks and make doubly sure it's sitting down correctly and bot wobbling around on the shaft.
In fact replace the rotor with a new one because there is a resistor built into it which breaks down and it's not unusual to find bad ones amongst New old stock .
Replace the condensor and check that the little earth tag on the points plate is intact and clean.
Check there is NO oil on the points contact face.
check the plate where the poits sit are clean
because I won't ASSUME anything,are the points set at the correct gap?
Is there ANY movement n the distributor shaft? Movement will prevent the points from opening and closing correctly. get the distributor overhauled if you can move the shaft side to side .
Check the earth tag from the distributor to the engine block and replace it if it is broken ( or missing)
Check the engines earth strap .
The connections in the main power terminal block Must be removed and cleaned .
Resistor plugs won't stop it running BTW.
recheck with the spark plug again .
if you still have no spark replace the coil AND the ballast resistor(s) with new items.
recheck the spark again.
If you now have spark and it won't start without ether ,you still have fuel problem,In fact your low volume is too low to enable the engine to start. It is NOT pressure but volume which the MFI needs.
Once the Fuel is OK,and it still wont go ,remove the cam cover.
Crank the engine until the mark on the cam washer is lined up with it's mark on the number one cam tower.
check the timing pointer on the crankshaft damper.
It must line up with the zero mark .
+or- 4-5 degrees will still get you going, butanymore indicates a worn or slipped chain.
Linear Mode
