w124 diesel pump

[GregZ]

Hi All,

I am new to the W124 (603.960) engine. As the car was out of diesel (like Bart Simpson would say: "I didn't do it") and I put some five gallons in it, I was looking for the manual hand pump to remove the air from the system. To my surprise where the pump is in my 300SD (on the side of the injector) there was just some kind of a connector. I tried to crank the car but the bubbles in the lines would not go away. So long story short: is there a hand pump, and if there is, where is it? If not, how is the fuel system vented?

Thanks for any and all the help,

Greg

[babymog]

The 60x engines are self-priming, you simply crank it to prime. I believe 20seconds max. at a time with 1minute or so between cranks, someone here might know the correct times.

I pre-fill the primary filter with ATF, makes it start sooner and ATF is already filtered.

[2.5Turbo]

The pump on the 60x is driven by the IP. There is no hand pump; you just have to keep cranking. I can't remember what the maximum cranking times are, but they are in the manual if you have it. Keep cranking it until the engine starts to fire evenly.

Since you only put five gallons in, it might be helpful to disconnect the supply line to the filter to gravity feed the fuel to the front of the car to get all that air out of there.

[TMAllison]

Helps also if the rear end is higher than the front and if the tank is >1/2 full.

I crank 30 secs at a time on my 606, rest 10, then crank again. After three cycles let the starter cool off a while and maybe re-charge the battery.

Is my personal opinion that on MY car if you wait very long between cranking you lose ground on priming. Others may have different observations.

[sixto]

I crack the big bolt atop the big fuel filter and crank until fuel leaks, then crack the injector lines and crank. Tighten the ones that leak. Lather, rinse, repeat.

Sixto
87 300D

[pberku]

On THIS engine, (OM 606) does anyone know which component in the fuel system performs the self priming, or how it is accomplished? Is that the Injector pump?

[TMAllison]

The "lift pump" does the work. Is a simple piston that pulls the fuel up from the tank. On drivers side of IP further back than the SOV. Very low fail part.

[sixto]

I don't understand how it self primes. Maybe easier to understand why older engines need a primer pump. Anyone know?

Sixto
87 300D

[WINGAS]

It doesnt do it well, that I'll say.