Found another abused car. The cool news is that my son, after seeing me work on these beautiful old cars, wants to have a go.

He can buy the car for 400, it is straight with 135k two owner miles. Car is not running as it has been sitting for over a year. Now I know that a diesel would probably fire pretty willingly after that amount of time but a gas car? I think not.

My only real question is that I am concerned that it might be that $500 fuel distributor and want to know how likely is it that that particular part would have failed after sitting. Though I don't have any direct experience with this part, it seems that if usually begins to fail and cause the car to run poortly rather than failing completely and disabling the car. The car will turn over with a bit gas right down the pipe, but it will not stay running so it it not getting fuel.

We figure we need to go from tank to injectors with seafoam hopefully but may be replacing filters and maybe the fuel pump and other components along the way. Any pointers or opinions are always welcomed and of course much appreciated.

Doug

__________________
1981 300TD
2005 C55
2004 E500
1999 ML430
1992 400E
1998 C43
2001 SL500
1988 300SEL
1986 190E 16V
1991 190E 2.6

I'm going through the same thing with an '85 500SEL ($300 delivered to my door in a "non-start" condition).

Check the forum posts for CIS problems.

The first thing to check is the fuel pump relay. Jumper the relay (it is located in the fuse box on the driver's side fender wall on my car). Pull the relay, (large black plastic box with a round "cap" on it), connect a jumper between the two rearmost side by side pair of contacts, and see if the pump engages. You will hear the pump "whir". Make SURE you have all the fuel lines TIGHT! Those vane style pumps spin the pressure up to 50 psi in no time flat.

If you hear the pump engage, disconnect the jumper, undo the fuel supply line to the distributor's front, left side (17mm wrench and a hold down bolt with a 10 mm head) and fit a rubber fuel hose over the end of the flair, I think a 3/8" hose will fit. Run the end of the hose into a 1 liter bottle sitting well away from the fuse box area, down on the ground or over on the other side of the engine, connect the jumper and check the flow. It should fill the liter bottle in about 30-40 seconds. Use a clear bottle and you will also have a view as to the condition of the fuel you are pumping. While you have the line disconnected, pull the fitting it goes into. You will find a strainer inside the fitting. Clean it out.

If you don't have the proper flow then change the filter. Do NOT bypass the filter or you will be making more problems than you already have! Go ahead and ask!

That's the FIRST steps to diagnosing the CIS systems. Do this first before attempting anything else.

The next thing to do BEFORE you do anything to the fuel system is to pull all the spark plugs and do a compression test. The M117 engines have a known weakness with the timing chain guide rails. If the rails have broken it is very possible it has bent valves or a "holed" piston. They are "interference" fit engines and a loose chain can be a catastrophic event.

While you have the plugs out, check for spark from the plug wires. The transistor box is a known weakness on all the early Benz'es.

What does "interference" fit mean?

Minimum clearance between the closed valves and the piston in the top position. essentially. There is no room for error if the chain stretches or jumps a tooth.

OK we went ahead and bought this car. When I looked at it and was told it had been sitting so long I assumed the battery was dead but little did I know the PO had tried to get it going and had dropped a new battery in it and guess what. As soon as I turned the key.... no fuel pump. So we found a good place to start. That and draining the tank.

Its a decent car if we can get it up and running. Thanks for the help!

__________________
1981 300TD
2005 C55
2004 E500
1999 ML430
1992 400E
1998 C43
2001 SL500
1988 300SEL
1986 190E 16V
1991 190E 2.6

OK we swapped the fuel pump out with a salvage unit and got nothing. Next we got a fuel pump relay and now still no power to the pump.

What is next?

I don't know if it is related, but there is a control unit, part #000 820 39 26 that is cycling/clicking for about ten seconds when the key is first turned on and cycles every so often if the key is left in the on position.

I have no voltage at the pump. Salvage pump has 3.8ohm resist. replaced pump has .9

And for what it is worth, if there is fuel present, the car fires right up.

__________________
1981 300TD
2005 C55
2004 E500
1999 ML430
1992 400E
1998 C43
2001 SL500
1988 300SEL
1986 190E 16V
1991 190E 2.6

Remember that you will only have power at the pump with the starter cranking or the engine running.

__________________
Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe

OK, the fuel pump from the yard was bad. I think they have another or I will try a third source today.

I disconnected the fuel line and ran a purge line to a gas can and jumped the fuel pump relay. Before I jumped it I measured 12V at the relay. Got nothing. So I need a good fuel pump.

I checked all the readings on my 420SEL and that pump is getting 13.3v at the pump and making noise. The other pump was getting 9v, making no noise and not moving fuel.

Not sure if I have a voltage prob to the fuel pump, but 9v seems low in relation to the 13.3v on the 420sel???????????????

__________________
1981 300TD
2005 C55
2004 E500
1999 ML430
1992 400E
1998 C43
2001 SL500
1988 300SEL
1986 190E 16V
1991 190E 2.6

9 volts is low but if I remember right you were checking the voltage while cranking the starter. A lot different than just jumpering the relay.

True story. The engine was running and generating current when I measured the 420SEL.

I am thinking as much of a hassle as its going to be, I might take the pump off the 420 and trying it on the 380 just to see if that is in fact the prob.

__________________
1981 300TD
2005 C55
2004 E500
1999 ML430
1992 400E
1998 C43
2001 SL500
1988 300SEL
1986 190E 16V
1991 190E 2.6

I give up! Mine beat me. I cleaned and re-installed the WUR, initial pressure dropped to 25 PSI, but the piston in the distributor stuck shut. System pressure was right at 70 psi with the check valve closed but the distributor gave up the ghost. I'm Megasquirting this beast!

Do you want all the CIS stuff I'm removing? Injectors with new seals (cleaned and marginal), new air tubes, new injector sockets with O-rings (one is bad, I nicked it removing the receptacles), cleaned and operable WUR, injector fuel lines, WUR feed and return lines, POS fuel distributor and all the other valves, relays and B.S. which goes to the CIS?

PM me with your address and I'll box the crap up and send it to you.

Oh oh.....

__________________
1981 300TD
2005 C55
2004 E500
1999 ML430
1992 400E
1998 C43
2001 SL500
1988 300SEL
1986 190E 16V
1991 190E 2.6

Wow, I think I am going through what you are dealing with. It started right up after new plugs and fuel line purge and we went to take it around the block and it quit after 50 yards.

Arrggggghhh

__________________
1981 300TD
2005 C55
2004 E500
1999 ML430
1992 400E
1998 C43
2001 SL500
1988 300SEL
1986 190E 16V
1991 190E 2.6

OK, I actually got to drive it. I got it started again and let it idle for several minutes and then gradually applied throttle and it kept running. I wound up driving it for about ten miles!!!! Runs pretty strong, trans seems to be good.

Brakes, drivers front, metal on metal. Power steering is leaking, both valve cover gaskets leaking. But at least we got something to work with!

__________________
1981 300TD
2005 C55
2004 E500
1999 ML430
1992 400E
1998 C43
2001 SL500
1988 300SEL
1986 190E 16V
1991 190E 2.6