Prechambers

Another question since I am new to this diesel thing. Can you remove and clean the prechambers or do you have to replace them?

[leathermang]

I am assuming you are referring to a MB 4 or 5 cylinder..
Yes, they are not even too hard to get out ( from the top )... and are supposed to be cleaned on a regular basis... they are critical to good fuel mileage. They have about 7 small holes at various angles and the warnings are like any precision hole cleaning... don't run something like a drill bit into them... soaking in cleaner and that sort of thing is the ticket....
Two types of remover are available... and I have read that the much cheaper one which mounts to a hand impact remover generally works fine. The more expensive screw type may be needed in hard cases.

PS.
BE SURE TO REMOVE THE GLOWPLUGS BEFORE REMOVING THE PRECOMBUSTION CHAMBERS......

[P.E.Haiges]

Leather,

What is the regular basis that the prechambers are to be cleaned? This is the first time I ever heard anything about cleaning them. Is there a MB maintenence spec to clean them?

How often do you clean yours?

P E H

[samiam4]

I don't think you ever need to clean them normally.

Maybe soak the heck out of them at rebuild time. The manual gives diameters, so you could buy a few drills or use gauges to check for wear.

They can clog up with carbon. Then soaking mmight help. I'd get as much loose stuff out as you can.


Michael

[leathermang]

PEH,
Do you not brush your teeth unless it is called for in the MB manual ?

1. Anytime the injectors are out anyway the precombustion chambers ought to be pulled and inspected.

2. Anytime there is a fuel usage complaint.

3. The holes can not be inspected without pulling them and having clean holes is very important. It also provides a way to check the condition of the cylinder walls. Pieces of glow plugs have been known to fall into the precombustion chamber well.. in addition to that bulbous pin potentially being eaten away. There is at least one engine which the factory called for changing the precombustion chambers to ones with larger size holes anytime the old style were out of the engine... or fuel utilization complaints existed.

I only put about 20,000 on my wagon before it was retired due to front suspension wear and ac repairs being too costly... the evap and the large hose were both leaking . It was getting 27 mpg out on the road so would not have messed with any fuel related items at that time.

If the screw type precombustion chamber puller did not cost so much money I would have pulled mine already on the 240. I trust the gradual application of force , which the screw type provides, more than I do the impact method... have broken too many old rusted things in my years...