Oil Filter Prelube

[Okieone]

OK, I know I'm going to get flamed for this, (forgive me Father, for I have sinned), I modified the original MB design.
I really don't like putting a dry, or even a pre-oiled filter in place at oil change time, and then firing the engine up, and listen and wait for the oil pump to fill the oil filter housing before going to 3 bar. I really feel this is wear that is going on that can be avoided with little effort. (Easy Boys, you don't know where I live, and I'm armed!, magnum bean flip, and a mean BB gun, so read on).
First thing is to put the correct "O" rings on the filter head stem, (no, they are not the same, the lower one as installed is 6mm x 10mm, and the upper is 7mm x 11mm. Don't believe it, take a dial caliper and measure the stem).
Now for the major modification, I took my dead blow hammer and knocked off the the filter housing head from the stem over a piece of carpet to prevent damage to the head, (careful, rap evenly on each side). Take the stem and drill and tap the upper stem to fit a sealed set screw to avoid problems with the the by-pass, ream the top housing to fit easily over the stem, be careful here and do not change the depth of how far the stem will fit into the filter head.
That's the modification, place the stem in place in the engine, fill about 1/2 full with the oil of your choice, and install the filter, slowly. Top off and install the filter housing head with new "O" ring for the head, and fire the old girl up. In my experience, you should see 3 bar in seconds.
Please understand I'm not posting this to sell anything, I'm just trying to keep my 617 alive a little longer, and maybe yours. OK, I'm done, let the flaming begin. And brother, if you have a better idea, I want to hear it.
Thanks
Okieone

[Matt L]

While this may not really be a problem with your setup, the danger is that the filter dislodges while driving.

One could ask, "the factory doesn't mandate this, so why bother?" However, I am not going to do so. I had a Saab 99 Turbo ('96, made it myself). When refilling the oil, I would always remove the fuel pump fuse and crank the engine until the pressure came up. Only then would I let it start. That's quite a bit harder to do with a diesel.

[Brian Carlton]

Originally Posted by Matt L

When refilling the oil, I would always remove the fuel pump fuse and crank the engine until the pressure came up. Only then would I let it start. That's quite a bit harder to do with a diesel.

If it really concerns you, just pull the glow plug connector............or turn the key to the start position without stopping in #2.............your choice.

Most older engines won't start for a few seconds..............or more...........without glow plugs at anything but very warm temps.

[Jeremy5848]

Originally Posted by Matt L

... When refilling the oil, I would always remove the fuel pump fuse and crank the engine until the pressure came up. Only then would I let it start. That's quite a bit harder to do with a diesel.

Actually not that difficult. Since you're already under the hood, use a remote starter switch and press the "STOP" lever on the IP while cranking. You can't see the oil pressure switch but you can have a friend watch for the first time and see how long it takes -- about 5 seconds? Next time, just count to five (or whatever) while cranking and the new oil will fill up the oil filter cannister.

[Matt L]

When I change my oil, the engine is warmed up. It will start without glowing.

[TheDon]

If Mercedes designed it a particular way.. it is meant to be that way...

It is not like the engine is bone dry, free of oil, etc etc when you change it.. I think the remaining oil within the system can compensate for the first few seconds before the pressure builds

[Matt L]

There is no STOP lever on my 606. However, if I cared, I could jumper the starter motor to crank the engine.

[bustedbenz]

The 606 doesn't have a manual shutoff??? Wow... what do they do to shut down 606 engines that lose vacuum lines? Different system entirely?

My 603 brings the pressure up to 3 bars within the first two seconds of running, at worst three, even after full glowplugs so it'll fire off instantly. I usually just hit the switch without preglowing it just for extra insurance... the way mine is, it has pressure up LONG before it fires up like that, warm or not.

[Matt L]

Originally Posted by bustedbenz

The 606 doesn't have a manual shutoff??? Wow... what do they do to shut down 606 engines that lose vacuum lines? Different system entirely?

Very different system. There's an electrical shutoff diverter valve, but there is also an electrical rack modulator, controlled by the computer. It's throttle-by-wire; there is no mechanical connection from the pedal to the IP.

[P.E.Haiges]

Okieone.

I my opinion and probably the opinion of the MB engineers, your modification is overkill.

P E H

[pawoSD]

I always just turn the key directly to crank and skip the glow after I change the oil. Engine is usually still fairly warm at that point, so it starts after about 6-7 revolutions....and about 3-4 seconds after that the oil pressure pegs. I also use synthetic oil, and synthetic really clings to the metal surfaces, it completely coats the lobes on the cam....even when the engine has been off for days or more. I am betting little to no excess wear occurs during those few seconds. Probably less wear than takes place in an engine starting up on 15w40 dino oil in super cold temps. So, I am not concerned.

[Chas H]

Starting the engine after a filter and oil change is little different from starting it in the morning. After sitting all night, the filter is empty and most of the oil in the lines and galleys is down in the pan.

[pawoSD]

Actually since the oil canister is essentially sealed, that seal holds the oil in there even if the car has been off for a while. When we start any of ours in the morning they peg the gauge within 1-2 seconds or less. It takes about 4-6 seconds to build pressure after an oil change.

I don't worry about it. These engines have survived for two decades with the stock oil system. I seriously doubt that modification will have any long-term benefit. But, if it makes you feel good...

[toomany MBZ]

You asked for it.

Got any pics?