Hi,

I recently was given this car as trade for some parts. It ran on vegtable oil previously and after a radiator failure was sitting for some months before I got it. All the veggie oil equipment was on it and I have never heard this vehicle running.

After spending hours searching and reading forums I am stumped and decided to reach out to you to help me start this beast.

This is what I have done:

Removed all the veggie equipment, purchased a new fuel filter head, all new fuel lines including the rubber and copper seal for the return line banjo bolt, and seal for the shut off valve. Verified all the fuel lines are routed properly.

Installed a new fuel filter and seal, new pre filter and verified the o-ring is in place and sealing.

I verified the shut off valve is getting voltage when turning over around 10v and it clicks when the ignition is turned on. The battery is new.

There are no visible leaks from the delivery seals.

When I turn the engine over it sucks fuel from the tank, there are plenty of bubbles and once i stop cranking I can see fuel run back into the tank from the fuel heater to pre-filter line. Not a vacuum bubble.

I hooked up a vacuum pump to the fuel filter out to shut off valve and it struggled to pull fuel from the supply line but got fuel from the return line. It almost seems that the return line is bleeding off pressure?

Is the banjo bolt on the return line a valve? because upon inspection i could blow throught it with no problem? The return line is full of fuel and fuel is moving through it when cranking. Could this be my problem.

Also, I have determined 4 glow plugs are bad but thought I would cross this bridge after I get rid of the bubble bath in the fuel lines.

I intend to direct feed diesel through the prefilter to see if this make a difference..but I already have the ass end of the vehicle in the air.

Sorry to burden you with this for my first post...Help!

Hi, and welcome! You're on the right path. To try and answer your questions:

It's normal for the fuel to back down to the fuel heater on shutdown.

The banjo bolt on the back of the IP is a fuel pressure regulator. (spring and ball)

The fuel strainer in the tank is likely plugged. Mine was plugged with black slime from regular diesel fuel. I can't imagine what would be in there from veggie oil.

__________________
-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250

Bypassing the Fuel Tank is a good idea.

No burden; your problem and the solution to it are going to help someone else that has the same problem.

The Fuel Pressure Relief/Overflow Valve on you Fuel Injection Pump has a small hole some were in it to allow Air to bleed out of it. On the same token that would allow Fuel to go back the other direction.
However, take a good look inside. Some Members have had the Plastic parts inside of it go bad.

There is Valves inside of the Fuel Supply/Lift Pump that ought to prevent the Fuel inside of the Fuel Injection Pump Housing from moving Backwards.

When Fastlane was here they used to carry a Rebuild kit for the Lift Pump:
Anyone ever replace the valves in the fuel lift pump?

606 Fuel Supply Pump Rebuild
http://www.peachparts.com/shopforum/showthread.php?t=288883


Also if you have a Fuel Heater the Seals in that have been know to go bad.

See if the Fuel still goes backwards when the Fuel Fill Cap is off.

__________________
84 300D, 82 Volvo 244Gl Diesel

Thanks for the input.

I'm going to take off the pressure relef banjo bolt to take a closer look. I want to make sure it is working and the right part. I recall when I was replacing the seal I could easily blow air throw it which doesn't make sense since it is a pressure valve.

I'm also going to use my vacum pump and draw fuel to the lift pump and see if it holds vacuum. If so I believe my problem may be the lift pump or the releif valve.

I'll report back soon.

Guesing the strainer is fouled and or there is some rotten rubber somewhere between the tank and fuel thermo at the cyl head.

Bypass the tank and see if it wants to run and move fuel from your temp tank and then tackle the strainer.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

Well I did a some troubleshooting over my lunch break.

1. I removed the pressure relief valve banjo bolt on the IP. I can blow through it? Does that mean it is defective? stuck open?

upon removal a considerable amount of diesel came out of the bolt hole... maybe a cup or two... Is this normal? And where does this fuel come from, the port on the back of the shut off valve or behind the lift pump.

2. I noticed as soon as I disconneted the return line banjo bolt, fuel line #32 (fuel heater to prefilter) filled right up. I don't think the tank strainer is the problem as fuel flows by gravity with no issue.

3. I then disconnected fuel line #83 from the lift pump and connected a vacuum pump to the lift pump. I expected to draw fuel through the lift pump, shutoff valve (line 74) and then the prefilter (line 56). No go I sucked air. I thought the you could draw fuel through the shutoff when not powered up.. was I wrong? It almost seemed like I was sucking fuel from behind the lift pump...could this be the problem?

Enough questions.... next time I'll post pictures of my project car... I warn you its in rough shape motor and body .... but now I need to get it running for the challenge.

Attached Thumbnails

 

fuelflow.JPG (image)

Set up a temp tank and see if it runs. Once it runs you can worry if its the strainer or the lift pump that isn't cooperating right now. Lift pumps rarely go bad BTW....

Keeping your old fuel lines (especially #1 in the attached photo) and cutting them and adding a length of tubing makes setting up a temp tank or doing a purge a snap.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

I am am afraid I have reached the limit of My suggestions.

I have not owned one of the newer vehicles and don't have access to a Manual that would give specific testing of components.

You need more specific help/info than My general knowlege on Fuel Supply Systems can supply.

__________________
84 300D, 82 Volvo 244Gl Diesel

This might be worth looking into. I think I might have some spares that still work somewhere.

I'm not sure what the minimum number of plugs that are needed to start, but the cylinders should have some heat in order to get the engine running.

__________________
2013 Volkswagen Jetta Hybrid SEL Premium (Sparky)
http://badges.fuelly.com/images/smallsig-us/193500.png

It's a car not a science experiment! Open the throttle!

It's rumored that the SOV reverses the fuel direction when it's in the off position. That might provide some confusing results when you are trying to diagnose things.

__________________
-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250

Hi,
As Kartek suggested, look at the tank strainer, this will be a good start.

You can blow on the valve, the pressure in it is really little, then no worries there.

I had trouble with the seal on the whole pre-filter assembly and by passed it, no more bugger for me there.

you need to refill the fuel filter in order to restart the car properly as it contain about 0.5 litre.

Doing the lift pump might help too, when I did mine there was a difference between the new non return valve and the old one.

Hope it help...

Olivier

__________________
E300TD year 2000. RUSTY SOLD
cost a fortune to maintain on the road
but run well on WVO
Second Merc died due to corrosion ( NOT rust) How can mercedes get away with that for so long?
Third lasted a month then went away...
Fourth now... Corroded too...

I'm going to set up a temp tank and bench test the S.O.V., If it checks out I'm going to Power it directly with the temp tank to see if this gets fuel to the injectors.
Once I verify fuel to the injectors I plan to plug in the car's block heater and roll it over when its heated up.

I believe the lift pump is probably not the problem since the the IP is filling with fuel and there is no evidence it is leaking or sucking oil. I have narrowed the problem down to the SOV, Pressure relief banjo bolt, or IP itself. Once I verify the SOV is working I am going to block of the return line to see if that changes anything.

Another question, I see an electric connector of the back of the IP, what is its purpose. Does it turn the injector rails on/off... just another thing I want to eliminate. Are there any fuses I should be checking?

Thank you everyone for the help... its greatly appreciated.

If you hear the SOV click when the key hits pos 2 it works.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

If by "back" you mean the part facing the rear of the car as opposed to the other "back" that faces the engine, then the wire you see there contains the rack positioning circuit and the rack position feedback circuit.

Essentially, ECU says "rack move forward" and the feedback tells the ECU "yep, it moved".

Now, it is possible to run the car with the side cover off the IP. This way, you can verify that the rack is indeed moving. It should do a full cycle when you switch the key on then settle down to a position about 6mm from the resting position.

__________________
-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250

I think I won't screw with the rack positioning circuit until i exhaust all other options

I tried to bench test the SOV last night and either it's shot or I'm not doing it right. I found directions onine that says pins 2 and 3 on the valve are for valve and 1 and 4 are for the fuel temp sensor. I hooked up 12 volts to pin 2-3 (from my batt charger) and got nothing, no click. Maybe I found my problem... although I'm sure it clicked before on the car. It's raining today but I will connect it back on the car to confirm.

If anyone has a used SOV available for sale let me know. I don't want to pay for a new one until I get the other issues on the car addressed. The body has serious rust behined the headlights, rocker panels, battery tray rear wheel wells and door bottoms. I bought a mig welder to play with over the winter. By the way, I am doing this for the challenge, most would scrap the vehicle.

I must say the Veg oil system made a mess of the motor, everything is coated and I think I'm going to find a lot of carbon when I get around to opening it up.