before i am corrected on the last post,i am not sure if the device thats inside the ip is a magnet or just a piece of steel that triggers the light(the magnet may be installed in the light tester) to solve my problen when setting an engine up i made a tool from a drill bit that fits precise and have checked it with a light tester and it works as close as the tester.
larry perkins
71 old cars

Larry,

I know this and as I said it tested and dripped for at least 35 minutes, but I am going through all of the checks and would be pleased to know that the problem is a simple replacement of the injection pump.

BenzDiesel

The overfilled crankcase was very likely a fuel leak in the IP flooding the oil with fuel. Pretty rough on the engine, that.

There are only two things that will prevent the IP from generating enough pressure to pop the injectors (assuming that the pump itself is OK) -- air in the pump or incorrectly installed pressure valves. If the pressure valves are in fact installed correcly, you will have very little fuel delivered for each pump stroke even with the control lever all the way over to full power -- total delivery is less than 100 uL per stroke at max delivery. This is a couple drops, so if you are expecting much more than that, you may think the IP isn't working. Fuel won't flow out of the IP with the pressure valves installed and the holders torqued down, it takes a couple hundred psi or so to lift them. This is so that the falling plunger will pull fuel into the sleeve while the line stays at pop pressure. Delivery will be restricted to the volume the governor is calling for.

If the pressure valve holder seals aren't sealing (this is a problem with this particluar pump not seen much in the ones on the 617 engines), you will get normal delivery with the injector cap nuts loose, but none to speak of actually injected, since the pressure in the line leaks off between IP plunger strokes. The line must stay at just below pop pressure so that the fuel is delivered as the plunger in the IP rises, otherwise injection will be very late.

I'm pretty sure you bleed the air out while testing the IP timing, but you need to be aware that this pump is known for holding air. It's possible that you have air in the lines as well, and this will prevent injection til you get it out.

Here's what I would do:

Install pressure valve holders by the book -- pressure valve goes in the holder with the spring on the stem, pointing up. New copper seals are a good idea, as they harden in use and can fail to seal if reused. If the pressure valve holders are factory installed, leave them be.

Loosen the injector lines at the injectors enough to let them leak (about 1/2 turn), and then crank the engine with the accelerator floored until no more air comes out. This may take a while, and at least one charge on the battery. When you have air free fuel, tighten the cap nuts (they don't need a huge amount of torque), recharge the battery, run the glow plugs, and attempt to start. Don't crank more than 30 seconds at a time, and allow the starter to cool off between cranking sessions, you don't want to have to buy a new starter, too!

It will eventually start.

I suspect your problem is air in the pump, lines, and injectors, and the only way to get rid of it on this engine is to crank it forever.

One other thing to check is the condition of the lines on the suction side of the lift pump -- they are old, hard, and likely full of cracks by now, and if so, you are likely sucking in as much air as fuel and pumping that directly to the IP. You won't get enough fuel delivery to purge the lines until you get the air out of the fuel filter, plungers, and IP body.

I wish Benz had left the lift pump on this model -- I'd rather hand pump for half an hour than crank the engine that long....!

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'm in the process at this very moment of checking to see how the plungers in the injection pump correlate to the 15 degrees ATDC and the engine's cylinder intake stroke. I'm trying to fully understand the illustration that H202 posted. I will test for the air in the system when I get back to that point. According to initial Mercedes Benz design or Bosch's design, this pump is supposed to bleed itself of air. And I know that once I get everything back RIGHT, the engine will start and bleed itself of air and I won't have to run a battery down in the process. I'm discharging batteries because there is a problem, somewhere in the fuel system. When I get it right, it will start right up like it is supposed to.

BenzDiesel

the 603 injection pump is rough to prime properly and if you have an air leak it will never develop the necessary pressure to open the injectors.loosening the pipe unions slightly at the pump will allow fuel to bypass the pressure valves and give you a false impression.if you can find an old VW filter assy with integral prime pump you can hook this into the supply fuel line loosen one of the pressure valve holders and prime the pump till air free fuel flows.i use this method now whenever i must work on the injection pump or injectors.

I see where the injection pump is syncronized with the cam shaft in terms of the engine's firing order. And it is possible to have the injection pump out of time and still have it installed correctly at 15 degrees After TDC as it relates to the engine's firing order, but don't know if the engine would run properly if the pump and engine camshaft weren't syncronized. The process is slow but it's going. I'll definitely be checking for air leaks once I'm satisfied that I have the injection pump and the engine's camshaft on the same page. And you are right, it's rough, when all of this expensive metal will not come together and do what it was designed to do.

BenzDiesel

on this pump there is port on the side whereby you can lock in the correct pump timing.
a special tool is required.
however i understand that an appropriate size bolt will work.
once the pump is "locked" and your crankshaft is at 15 degrees the engine is "timed".
i really beleive you have an airlock in this pump.
a similar situation almost drove me to the brink last year.
cranking the heck out of it will bleed the system but you run the risk of damaging your starter and your neighbours nerves

Hello BenzDiesel well working on heavy equipment in order for the injector to pop it had to have at least 250 pounds have ya thought maybe pull one out turn one of the line out give it a few cranks to see what kind of spray it putting out it would be strange for all the injector be bad unless water got into them i know one thing is the pump and the injectors don't like water to well and check the tip of the injector see if it still has a good tip on them and if ya do have to take the injector apart there not hard just be sure you dip the part in a mix of diesel fuel and gasoline check for any scaring and the plunger should have a tight fit with no dragging you know that the pump only shut down pressure so you can shut down the engine

The timing issue is quite simple. Bosch added a hall effect "nipple" to the governor assembly to permit dynamic timing, and it just happened that the "nipple" goes past the point where they could put the pickup sensor hole at 15 degrees after TDC. The pump actually operates exactly like earlier ones. This was done in 84 or 85, as some later W123 models have the same setup. Some W123 turbo IPs were assembled with the injection pump cam 180 degrees out, but none of the 603 pumps have this quirk, so if it's set at 24 degrees BTDC by drip method and 15 ATDC by hall effect pickup, the timing is fine.

That IP with no hand pump can take FOREVER to purge when empty, much worse if you changed the fuel filter as well. The only real cure is to crank until it finally gets the air out, and if you have fuel and air coming out of the injection lines, it's purging, keep cranking. It's rather unlikely you will get it to start on one battery charge, and if the suction side lines are leaking air in, it won't start until you replace the lines. It will run with leaking suction lines, but if you ever get enough air into the pump to prevent easy starts, it won't prime well enough with the air leaks to ever start.

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!

Hello BenzDiesel
I suggested the use of channel locks because not everyone is strong.
One of my friends owns three diesel MB and has Multiple sclerosis.
RE: Whunter mentioned trapped air and the auxiliary fuel pump could possibly be the culprit. But then H202 had a spare pump and confirmed that channel locks were not needed to depress the auxiliary fuel pump's plunger mechanism.

Hello BenzDiesel
I suggested the use of channel locks because not everyone is strong.
One of my friends owns three diesel MB and has Multiple sclerosis.
RE: Whunter mentioned trapped air and the auxiliary fuel pump could possibly be the culprit. But then H202 had a spare pump and confirmed that channel locks were not needed to depress the auxiliary fuel pump's plunger mechanism.


OK whunter,

About the pump, it takes some pressure to depress the plunger, but most mechanics, if not all of them, should be able to depress a plunger on that particular pump with ease and I still have that as the potential culprit. If the mechanic can't handle that pump there is no way he is going to be tossing a 603 cracked head around. As always, I'm thankful for any information that even has a chance to be beneficial in solving my fuel issues.

BenzDiesel

Sorry I couldn't read every long rant, so forgive me if this has already been answered:

1) WHAT EXACTLY makes you think there is no fuel being delivered from the injectors to the prechamber?

2) How long have you cranked the car with your foot on the floor? When I replaced my head it took something like 3 minutes of cranking before it fired. That's with a totally dry fuel system.

3) You're saying the *bottom* of the inejctors are BONE DRY?

4) Did you use the proper lock tool to install the IP and then verify timing with the same tool after rotating the engine 2 revolutions?


Please let's stay off the head crack thing - that's way off topic of a fuel delivery issue. Lots of information already out there on the #14 head. Mercedes had a design flaw for the first few years of production (say, through 1988 or so) but the later years were fine (say, 1988-95) and remember that the 603.96x was sold in enormous numbers worldwide, despite low shipments to the USA due to annoying EPA regs. The Finns are routinely getting over 400hp out of a stock 603 long block, so it's definitely not a weak engine design. Driving with a light foot is BAD, btw... worst thing you can do for an IDI diesel is piddle around at part throttle all the time and never rev it over 3000rpm. Drive it like you stole it - frequently.

__________________
Dave
Boise, ID
Check out my website photos, documents, and movies!

the engine compression does not effect the injector if you are get fuel or not but the engine compression dose effect if you want it it ignite the diesel fuel diesel ignite by the compression and by the cycle compressing the fuel and air so tight that the friction and compression kick the fuel off all low compression will do is puff out white smoke (unburned diesel) SEE on Hazts diesel which is the top of the line German industrial engine the piston goes up in to the head 2mm pass the block surface so that is way timing (it will knock out the valve) is important
on hazts they use a copper ring as a head gasket which i use some lead turn the engine by hand hit the lead then take it out to measure the thickness
hope the help some just remember you getting fuel or you are out of the pump or you might check to see if the pump is in the full open not close or half way close you need to have enough pressure out of the pump to pop the injector springs

I am not getting any fuel to pop the injectors. That is the problem, period. I have to time the injection pump and my fuel injection problem will be solved. I spent all day today hoping to see has anybody else seen what I saw about the inner workings of this 1987 300SDL Diesel. But I guess you have to have gone through that 603 engine backwards and forward like I've done to even know what I'm talking about. Several of the guys here are shooting in the right area, but none so far has said anything to let me know that they fully understand what is going on with this engine from an engineering standpoint.

BenzDiesel

**sigh**

No. An incorrectly timed pump will still squirt fuel - just at the wrong time. I asked before, and you did not answer, how long have you cranked the engine? Several minutes worth after buttoning up the entire fuel system - yes or no? And have you taken Casey's advice to remove the side cover and make sure the rack is moving out of the stop position?