Greetings All,

My 80' 300cd is not starting. I came home last night, parked it in the driveway and now nothing. I did a couple short trips out in town and came back home. It is not very cold out here right now maybe into the mid 60's. However, I replaced the glow plugs this morning, checked the relay and it is fine, replaced fuel filters, primed the engine and still nothing. I thought that maybe the battery was going and tried to jump it still nothing. The engines cranks attempts to turn over but that is it. A little blue/white smoke after every couple of attempts or so. No matter how many times I try to crank it over it does not catch.

How would I go about checking the fuel delivery system. The threads here are a little vague to me? Or does anyone have any other Ideas?

Thanks,
Brian

Brian:

No white smoke means no fuel. Check by opening the return line and pumping the hand pump -- if you don't get good fuel delivery, at least 10 ml or so per stroke, you aren't getting fuel to the IP. You can also check by loosening the injector lines at the injectors (17 mm wrench) a half turn or so, then cranking with the accelerator to the floor. If you don't get quite a bit of fuel running down the injectors, you don't have fuel in the pump.

Most likely cause is a bad suction line or plugged tank screen, followed by bad hand pump if you still have the old red handled one that screws down. If so, get a new one, it is spring loaded and doesn't leak anywhere near as much.

If the hand pump pulls up hard, try blowing down the suction line into the tank -- this usually blows enough crud out of the line to let you start the car.

If you find a leaking line, make sure you get the fuel system completely full or it will take forever to start. You will need to bleed the IP -- there is a slot-head screw on top that can be loosened to allow the air to get out.

I suspect the clear lines to the IP and fuel filter are so dark now you can't see through them, but if you can, if you get bubbles in the fuel while operating the hand pump, you have a leaking pump of suction line.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Where exactly is the IP bleeder valve?

It's a slot-head screw on the top of the pump, at the rear. Exact position depends on model.

You can also pump forever and loosen the return line, but that will not purge the air out of the fuel gallery where it goes into the sleeve/plunger sets.

It is usually fairly obvious -- a slot-head screw that doesn't hold anything down.

A buddy of mine has bought five or six W115's over the years for a couple hundred bucks, usually only needing new fuel lines to work properly!

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

I get good suction when I operate the priming pump as fuel is entering the pre-filter and the handle comes up pretty easy. It can't be a clogged tank screen or fuel line from there. When I push the priming pump handle down fuel goes through the main fuel filter and through the clear fuel lines to the IP. I noticed some fuel that was escaping the priming pump handle but that was normal last time I changed the fuel filters. I also noticed some small bubbles in the clear fuel line that is attached to the top of the main fuel filter but that was it (Return Line?).

I looked at the IP today and I still do not see a bleed screw anywhere on top. I might be looking in the wrong place. Can it be somewher in the sides or near engine?
The Injecter lines are of course on the left and near the back of the IP on top I just have a part that looks like a valve and four bolts holding that down. Is it near the shut off valve? I looked in the haynes manual as well and there is nothing in it about bleeding the IP or in any of the pictures.

Thank You
Brian

Brian:

Some pumps may be self-bleeding -- if the fuel return line is at the top of the pump, just below the pressure valve holders, this may be the case.

I suspect your priming pump is shot -- mine leaked fuel, and it turned out to be doing nothing at all. Get the new one, it doesn't leak and you don't have to screw it down. Much nicer.

Try loosening the return line on the pump (it goes to the line that goes back to the tank) and pump the priming pump. You should have quite a bit of fuel running out -- if not, you don't have any in the IP and you won't get the car started.

It is also possible that you have too slow a cranking speed -- is your batttery in good condition and fully charged, and does the engine crank at normal speed? If it doesn't go at least 100 rpm, it won't start.

Are your glowplugs working properly? Again, no start if they aren't hot.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

What exactly does"the engines cranks attempts to turn over" mean and where is the battery "going" to?

If you would be more specific with your description of your problem, I could be more specific with my answer.

Does the starter crank the engine at the same speed (RPM) it always did? If not, then the problem is the battery, starter, cable connections or corroded battery terminals. The starter should crank the engine at 100 RPM or more.

Does the engine fire at all? If it does, the glow plugs are working but not enough fuel is being delivered to the cylinders. It is unlikely that that this would happen by just shutting off the engine and then it wouldn't start on the next try. It might have happened when you took the fuel system apart when you replaced the filters.

Do you have a manual transmission? Do you have a hill where you could try a roll start? If this starts the engine, it would eliminate the fuel and GP problems and point to the starter or battery.

P E H

Sorry P.E.H. for being too vague.

The starter does crank the engine at the same speed as before.

The battery was showing 25.6 and rising today at my local Autozone.

The engine does not fire at all. There is no smoke when I try to crank the engine now. However, I tested all five new glowplugs and all of them are good. Two were bad before so I decided to replace them all.

There is no air in the filters, however, today I did hear a squeaking sound when I operated the hand pump. I have ordered a new one, should be here by wednesday.

Today, I have also noticed that the ends of the overlflow tubes were wet and cracked. When I pulled the overflow tube off of the #1 injecter to replace it(only have 1 foot of proper size tubing) there was no fuel that came spilling out. I put the end of the #1 over flow tube in a bottle of diesel and operated the hand pump. Fuel came out after about ten strokes. Then the fuel in the bottle was sucked back up into the system. Put the #5 overflow tube in the bottle, no fuel came spilling out and the same thing happened. I will replace the rest with new rubber lines tonight. I do know that the fuel system is pressurized so I hope this is normal.

There was hardly any fuel in the cigar hose(as fuel coming out) when I took it off at one end. I pumped the hand pump several times and only small squirts of fuel were coming out. Is this normal?

I have an automatic transmission, so roll(push) starting is not an option.

Brian-

Brian:

You have a defective hand pump. It is also possible that the check valves in the main fuel pump are bad, but I've never heard of this actually happening. New pump should fix the problem.

I'd also loosen the injector lines at the injectors and crank until air-free fuel appears there after you get the hand pump replaced. You will need to completely purge the air out before the car will start.

Unless the newer (722) tranny is radically different that the older ones, you CAN push (or pull) start your car -- run up to about 20 mph in neutral then drop into 2nd -- motor will crank. If it doesn't start, let it cool for 15 min before trying again. MB normally uses a secondary pump driven off the output shaft for governor pressure and control pressures. It is large enough to drive the tranny about 20 mph.

However, if you don't have fuel deliver with the hand pump, you won't get fuel delivery with a pull start, either, as the check valve in the hand pump is allowing fuel to suck back from the filter.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

When my starter died I parked on top of the hill and dropped it into L as it hit 15-20 mph. instant fire every single time. Worked well for a month till I got the new starter and installed it.

__________________
Matt
2003 Jetta Wagon TDI 145,000MI
1999.5 Jetta TDI 287,000MI
2001 Suzuki SV650S 26,000MI
2008 Yamaha Vino 125 11,000MI
http://www.crazymatt.org

baporter,

I have no idea what "my battery was showing 25.6 and rising" means. 25.6 what? The only real test of a battery is when it is subjected to a high current load such as cranking the engine.
If the starter cranks the engine as it always did, there is nothing wrong with the battery or starting system.

How did you test the glow plugs? If you replaced them all its not a problem with the GP themselves. Take one of the old GP, one you know is good, and clamp it to a good ground with a locking pliers near enough to connect one of the wires removed from any of the other glow plugs and connect that wire to the clamped GP. You will now be able to observ what the GP inside the engine are doing.

If the GP you can see does not glow brightly when the key switch is turned to the pre glow or run position the problem is in the GP electrical system. Have you checked the fuse in the GP relay? If the fuse is OK it might be a bad GP relay. The fuse can have a hair line crack even though it looks good.

Do the above test and let me know the results.

You should get a sort of buzzing noise when you pump the hand pump. This is the fuel going past the pressure relief valve in the injection pump (IP) and is normal operating procedure. When this happens, the IP is purged from any air that may have been in it. Your hand pump is probably OK.

The way the fuel system works is that it is sort of constant flow. The fuel pump pumps the fuel against the resistance in the IP relief valve which creates pressure. The relief valve opens at a predesignated pressure and the excess flow is returned to the fuel tank. The over flow from the injectors is also connected to the return fuel line. There is also a tiny hole in the top of the secondary fuel filter which automatically bleeds air from the filter. So by pumping the hand pump, the system is purged from any air. The lines from the IP to the injectors are purged automatically when the IP pumps fuel to the injectors.

P E H

Roll starting with an automatic is more difficult than with a manual. Be careful because the brakes and steering will barely work. I think it is better to go down a hill than trying to push with another car. If you do push with another car, back off with the push car before trying to start the non runing car. With a auto, you need a big enough hill to get to 30 MPH so for safety's sake, it is probably better trying to start the car using the starter.

P E H

PEH:

If the old style hand pump is bad, it doesn't draw fuel from the tank, just pulls it back and forth, and allows air to get sucked in by the lift pump. No way you will ever get it started until you get full pressure and decent fuel flow in the IP.

Most Bosch IPs have a restriction in the return fuel fitting rather than a spring valve -- the spring valve is usually in the fuel filter, not that it matters much. It DOES if you get the restriction in the supply side! The VE pump on the Volvo doesn't have a pressure valve at all, other than the restrictor on the fuel return -- the filter is on the suction side.

I've only tried to roll start my 220D once, and the hill wasn't long enough! Spent about an hour digging around (in the dark!) up against the exhasut manifold with a pair of pliers trying to jump the solenoid -- the neutral safety switch had just died and I stalled the d.... thing turning around after looking over a 190E for sale. Stupid.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Psfred,

Maybe a bad hand pump but what caused the no start condition in the first place? This wouldn't be caused by a bad hand pump because it was not screwed open and used until after the no start problem was present.

I think it might be a GP problem exasterbated now by a no fuel problem because the fuel system was opened.

P E H

All five GP glowed red hot. I checked each GP with all five GP wires just to make sure. It is not the GP relay or the wiring.

Operated the hand pump again this morning and noticed more bubbles in the return line from the bypass valve to the banjo connecter.