Car is 1983 240D with OM616. 208K miles.
Injectors are en route back after rebuild by C Sean Watts. Meanwhile I have purchased new heat shields and in comparing them with the old ones, the hole seems larger on the new ones. I did a search and found reference to 7.5mm and 10mm shields and was wondering if this is what I'm seeing. Is this a problem?
Also, how hard are these things to remove? I saw a dental pick mentioned and I can probably make a hooked wire but mine seem pretty tight.
Thanks in advance!

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1983 M-B 240D-Gone too.
1976 M-B 300D-Departed.

"Good" is the worst enemy of "Great".

both sizes are available and work. However, the smaller is more desirable as it protects the nozzle better and provides a smaller surface area for sealing the chamber.

They usually come out with a magnet.. but sometimes more force is required.

*I just thought of something.

The larger ones may be intended for use after the nozzle surface has been eroded and no longer provides a smooth sealing surface.

Reaching the outer perimeter of the nozzle tip with the larger-hole heat shields is the best bet to ensure a good seal if there is any pitting on the nozzle after an extended period of use.

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Are you talking about the ones with the larger hole and the smaller hole? IE:



VS



The bottom one is used on VWs. Why the two makes use different heat shields for the same injectors I don't know.... something with the differences between the 'benz prechambers and VW swirlchambers?

-Jason

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

My preferred technique is to use needlenose pliers. Insert them into the hole in the center with the pliers closed, then hold them open to grip the heat shield, gripping the inside of the hole with the outside of the pliers.

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-Brian

1984 300SD, 375XXX miles, Light Ivory w/ Palomino TEX

Its easy to take them off. Use a "conic" screwdriver, push it in hard enough, twist it, and off you go, the old washer comes out

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E300TD year 2000. RUSTY SOLD
cost a fortune to maintain on the road
but run well on WVO
Second Merc died due to corrosion ( NOT rust) How can mercedes get away with that for so long?
Third lasted a month then went away...
Fourth now... Corroded too...

Hey, thanks for the advice. I guess no need to be afraid of applying too much force.
I'll get pix of the new ones later. This is from memory (after looking at them last night) but it seems the hole is bigger and the "channel" is narrower than the pix above. The old ones look like compu 85's and Olivier's pictures.

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1983 M-B 240D-Gone too.
1976 M-B 300D-Departed.

"Good" is the worst enemy of "Great".

That works.
I also use a three inch lag bolt.
Insert, quarter turn to lock it, rock it to break loose the seal, and it comes out on the bolt every time.

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Here's what I'm talking about.
And the screwdriver wedge trick worked although the shield was quite tight.
Sorry about the photo clarity. Ya does the best ya can with a phone cam.

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1983 M-B 240D-Gone too.
1976 M-B 300D-Departed.

"Good" is the worst enemy of "Great".

All of them I have seen look like the smaller one. but I have only seen the ones on my cars.

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83 300SD Dark Silver Dark brown inside

I've used both sizes. But I prefer the smaller size. After using them and upon inspection, wear area showing on the nozzles is greater with the 10mm size as opposed to the 7.5 mm sized. But running them, there was no noticable difference.




.

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1983 123.133 California
- GreaseCar Veg System

The Injector Heat Shields that came off of my Car had the small holes. The ones I ordered for the Car came with small holes. And, it appeared that my Injectors were the origionals that came with the car.
When removing Injectors at the Junk Yard; they also had the small holed Heat shields.

The same supplier I bought the small holed ones from now is sells the large holed ones for my car.
So as fare as I know they are interchangable.

However, as the other member said I bought the small holed ones recently from the same supplier buy odering VW Rabbit Heat Shields.

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84 300D, 82 Volvo 244Gl Diesel

Thanks for all the info. I'm gathering that I can use the larger holed shields but nozzle longevity may suffer. I'll probably install what I have when the injectors come in and the next time I get parts I'll try to get the smaller holes and swap them out when I'm bored.
Thanks again!

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1983 M-B 240D-Gone too.
1976 M-B 300D-Departed.

"Good" is the worst enemy of "Great".

If you do that you will need to find a safe way to clean off the Carbon Build up in the area that the Heat Shield does not cover. Meaning there will be Carbon in the sealing area of the small holed Heat Shields.

I have used a fine wire Brass hand Brush for this but there are some who would object to that.

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84 300D, 82 Volvo 244Gl Diesel

Also I like to add that if you use the 10mm holed heat shield and there is any pitting or distortion in that area, you should use a 10mm holed heat shield because the 7.5mm will not get a proper seal.





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1983 123.133 California
- GreaseCar Veg System

I just thought of something.

The larger ones may be intended for use after the nozzle surface has been eroded and no longer provides a smooth sealing surface.

Reaching the outer perimeter of the nozzle tip with the larger-hole heat shields is the best bet to ensure a good seal if there is any pitting on the nozzle after an extended period of use.

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