Replacing Injection pump-Engine block gasket

Mercedes 240D 123.123 619

Finally, I got around to replacing the gasket
between the injection pump and the motor block.
What a massive amount of work to replace such a
small gasket! It seems that cars just were not
designed with servicing in mind.

I could not find the Hylomar Blue and, based on a
discussion in this group in the past, I picked
Aviation Permatex from a lot of others. It is
supposed not to harden and that should make it
more effective in the long term. What surprised
me is the width of this gasket and the width of
the metal-metal contact. In places it is only
3/16". I would think that a wider bearing surface
would give much more resistance to leaks.

Of course I had to remove the complete injector
pump, after disconnecting the vacuum line (just
pulling it off the pump), the two control rods,
and the eight fuel connections:
1 Below the hand pump - the fuel inlet from the
tank via the small transparent filter.
2 Right beside No. 1 - again below the hand pump -
is an outlet that goes up to the top of the main
fuel filter.
3 This is the fuel outlet from the main filter
down to the front connection of the injection pump.
4 This one is the fuel return line that starts on
the engine side of the injection pump, goes to the
top of the main fuel filter and then attaches to
the return line that goes back to the tank.
5 The other four are the metal fuel lines to the
injectors.

Lastly, I removed the three nuts and washers that
held the front of the pump to a bracket at the
front of the engine, and another three that fixed
a small bracket to the rear of the pump and to
the engine block. The pump then was removed,
with the rear end down to keep the oil from
running out the front. I placed it level on a
bench top and noticed the oil coming out the
front. That was the area where the gasket was to
be located and, to prevent any more oil mess, I
turned the pump with that end down and drained
about two cups of oil. I sure didn't want it
dribbling out after I had the gasket and cement in
place.

The Permatex - Aviation comes in a 4 oz bottle
with very few instructions. Basically: "Apply to
thin film to each surface. Allow to air dry for a
few minutes before assembling." This was all that
applied to what I was doing. I went online and
came up with a PDF (
http://www.permatex.com/documents/tds/Automotive/80017.pdf)
that gave far more instructions. What about
people who can't go online? Undoubtedly everyone
has noticed that the instructions in English on
all containers are getting less all the time, to
make room for the Spanish traslation. Another cost
of the illegal migrations? When will we learn?

The gasketting went smoothly but, when I had
everything reassembled, I had trouble starting the
engine. I had released the air on Line 3 at the
main fuel filter and, after the bubbles stopped, I
tightened the nut and went on to Line 4 where it
attaches to the main fuel filter. While doing the
manual pumping I noticed a stream of fuel heading
downwards. I had oscillated the plunger up and
down by about 1/4" on each stroke and I guess that
it is worn or defective. I set up two plastic
containers, one under the main fuel filter, and
the other below the injection pump and then
vigorously repeated the venting. When I was
finished the container around the main fuel filter
had about a cup of fuel and the other one had
about three. I tried a few times to start the
engine and it came very close at the last try. I
stopped and the battery is now recharging. It
seems like I am near the end.

What a ghastly, messy, stinking - especially in a
hot garage - and primitive process this is. Why
not a liquid-air separator valve attached to the
tops of lines 3 and 4 with the air line heading
into the air intake and the liquid heading into
the return line to the tank? Now that would be
civilization! Anyone heard of such a gizmo?

Is it possible to buy the manual pump plunger
itself, or the washer that presumably attaches to it?

I want now to stop all the drips from the engine
and I noticed that there was a small leakage at
the corner of the cylinder head gasket - the left
front side. I tightened the nuts to the correct
torque and I suspect that the cover may be a
little distorted. The gasket is only a few years
old. I am thinking of removing the cover and
gasket to clean them up and then use the Permatex
at that corner, or possibly the complete gasket.
This sealant seems to have an alcohol base so I
doubt it would bother the plastic of the gasket.

I won't be able to identify other leaks until I
get the car to a radiator shop to have the engine
box and the outside of the radiator very clean.
Anyone know what this typically costs?

In my experience, MB does design with servicing in mind. Most jobs
require limited number (usually only one) of tools. For example, oil
change (13mm socket or wrench), brake, alternator, light bulbs (your
fingers, most time), etc. I had at least twice experiences on GM cars
where both metric and SAE are used on a same job.

Injection pump itself usually does not need service. Removal is even
harder, especially because it needs precise timing when putting back. I
assume that is why the engine does not start now. For later diesel
engines (OM60x series), adjusting timing requires special tool (probably
dealer only). I am not familiar with OM619. You may need to think
about sending to repair shop.


RF wrote:
> Mercedes 240D 123.123 619
>
> Finally, I got around to replacing the gasket between the injection pump
> and the motor block. What a massive amount of work to replace such a
> small gasket! It seems that cars just were not designed with servicing
> in mind.
>
> I could not find the Hylomar Blue and, based on a discussion in this
> group in the past, I picked Aviation Permatex from a lot of others. It
> is supposed not to harden and that should make it more effective in the
> long term. What surprised me is the width of this gasket and the width
> of the metal-metal contact. In places it is only 3/16". I would think
> that a wider bearing surface would give much more resistance to leaks.
>
> Of course I had to remove the complete injector pump, after
> disconnecting the vacuum line (just pulling it off the pump), the two
> control rods, and the eight fuel connections:
> 1 Below the hand pump - the fuel inlet from the tank via the small
> transparent filter.
> 2 Right beside No. 1 - again below the hand pump - is an outlet that
> goes up to the top of the main fuel filter.
> 3 This is the fuel outlet from the main filter down to the front
> connection of the injection pump.
> 4 This one is the fuel return line that starts on the engine side of
> the injection pump, goes to the top of the main fuel filter and then
> attaches to the return line that goes back to the tank.
> 5 The other four are the metal fuel lines to the injectors.
>
> Lastly, I removed the three nuts and washers that held the front of the
> pump to a bracket at the front of the engine, and another three that
> fixed a small bracket to the rear of the pump and to the engine block.
> The pump then was removed, with the rear end down to keep the oil from
> running out the front. I placed it level on a bench top and noticed
> the oil coming out the front. That was the area where the gasket was to
> be located and, to prevent any more oil mess, I turned the pump with
> that end down and drained about two cups of oil. I sure didn't want it
> dribbling out after I had the gasket and cement in place.
>
> The Permatex - Aviation comes in a 4 oz bottle with very few
> instructions. Basically: "Apply to thin film to each surface. Allow
> to air dry for a few minutes before assembling." This was all that
> applied to what I was doing. I went online and came up with a PDF (
> http://www.permatex.com/documents/tds/Automotive/80017.pdf) that gave
> far more instructions. What about people who can't go online?
> Undoubtedly everyone has noticed that the instructions in English on all
> containers are getting less all the time, to make room for the Spanish
> traslation. Another cost of the illegal migrations? When will we learn?
>
> The gasketting went smoothly but, when I had everything reassembled, I
> had trouble starting the engine. I had released the air on Line 3 at the
> main fuel filter and, after the bubbles stopped, I tightened the nut and
> went on to Line 4 where it attaches to the main fuel filter. While
> doing the manual pumping I noticed a stream of fuel heading downwards.
> I had oscillated the plunger up and down by about 1/4" on each stroke
> and I guess that it is worn or defective. I set up two plastic
> containers, one under the main fuel filter, and the other below the
> injection pump and then vigorously repeated the venting. When I was
> finished the container around the main fuel filter had about a cup of
> fuel and the other one had about three. I tried a few times to start
> the engine and it came very close at the last try. I stopped and the
> battery is now recharging. It seems like I am near the end.
>
> What a ghastly, messy, stinking - especially in a hot garage - and
> primitive process this is. Why not a liquid-air separator valve
> attached to the tops of lines 3 and 4 with the air line heading into the
> air intake and the liquid heading into the return line to the tank? Now
> that would be civilization! Anyone heard of such a gizmo?
>
> Is it possible to buy the manual pump plunger itself, or the washer
> that presumably attaches to it?
>
> I want now to stop all the drips from the engine and I noticed that
> there was a small leakage at the corner of the cylinder head gasket -
> the left front side. I tightened the nuts to the correct torque and I
> suspect that the cover may be a little distorted. The gasket is only a
> few years old. I am thinking of removing the cover and gasket to clean
> them up and then use the Permatex at that corner, or possibly the
> complete gasket. This sealant seems to have an alcohol base so I doubt
> it would bother the plastic of the gasket.
>
> I won't be able to identify other leaks until I get the car to a
> radiator shop to have the engine box and the outside of the radiator
> very clean. Anyone know what this typically costs?