Hello everyone!

Previously I posted thread about buying #10 head, that in the end was returned back to seller:
Wrong 3.5L head for my 3.0L OM603?

I have found a #20 head, that have no cracks or corrosion. Planning on preparing it as much as I can for a head swap for my cracked #15 head I have now.
One thing that I was dissapointed about is the fact that this head hasn't got 3 prechambers in it, other 3 prechambers look little bit different from mine. Seller said that these prechambers are just missing some parts.

It looks like I will just have to put in mine prechambers.
Here is the problem/concern. #20 head should have the same inclined injectors as mine #15 if this head haven't been machined to old prechambers. There are some marks of some work for prechambers. This is why I am concerned. I have no expirience on working with prechambers. In previous work I have allways kept them untouched.

Could someone tell me if these prechambers are inclined or non-inclined?
If prechambers are non-inclined could I fit mine inclined prechambers to these ports in #20 head?

Would be thankful for any information/opinion!

2 Pictures attached - with and without prechamber.
Higher quality pictures here (onedrive):
http://1drv.ms/1BTrn2U

Regards,
Vilnis

Attached Thumbnails

   

__________________
1989 300D Turbo, w124 sedan, OM603 + 722.3

.

it seems that injector threads directly into the pre-chamber ring
so it is non inclined..but wait for bigger 603 gurus to confirm..

cheers
.

__________________
w126 500SEC gen II euro, powered by OM617 turbo stolen from 84 300SD 2.88 diff,EGR blinded
next wish/project: w114 coupe OM603 powered

Thanks for the response.
Seller said that lock rings are missing. I believe he meant splinned prechamber lock rings.

__________________
1989 300D Turbo, w124 sedan, OM603 + 722.3

The prechamber is inclined, not the head so the picture of the pocket in the head says nothing. Not sure what cho means but I see a set of threads in the head for the lock ring and a set of threads in the prechamber for the injector. That suggests inclined injection. Injectors for vertical prechambers thread into the lock ring. Vertical prechambers don't have internal threads for injectors.

Someone mentioned in your other thread that naturally aspirated engines have different diameter prechamber tips so you might not have the option of moving prechambers from the #15 head. Compare the diameter of the exposed tip first. If they're different, don't waste your time with those prechambers. It seems odd that a #15 head has inclined prechambers but you know what you have.

Sixto
MB-less


Sixto
MB-less

Hello Sixto!
Isn't the#20 head a turbo head?
As I have understood from reading forums only head that originally had non inclined injectors is #14 head. My #15 head doesn't have any machining signs and I have those toothed lock rings. The same as that sad #10 head had which turned out to be with inclined injector prechambers (at least forum members said so).
I have never dealt with or seen different prechambers so I have hard time to find out differences.
It would be hard to compare mine prechambers with these as mine are on the car which I plan to drive for a while until I am ready for swap.

If these are prechambers for inclined injectors then I think it should be ok. If it is not then I have to know if head modification is backward compatible?

Regards,
Vilnis

__________________
1989 300D Turbo, w124 sedan, OM603 + 722.3

pic:

Attached Thumbnails

 

__________________
w126 500SEC gen II euro, powered by OM617 turbo stolen from 84 300SD 2.88 diff,EGR blinded
next wish/project: w114 coupe OM603 powered

603 n/a

603 016 10 01
603 016 16 01

603a

603 016 14 01
603 016 15 01
603 016 17 01
603 016 18 01
603 016 20 01
603 016 22 01

be aware (as you a euro guy) ,many of turbo 603 owners put/swap n/a heads!

cheers

.

__________________
w126 500SEC gen II euro, powered by OM617 turbo stolen from 84 300SD 2.88 diff,EGR blinded
next wish/project: w114 coupe OM603 powered

That seems to be the thing done in a head that bought previously. Seller tried to encourage me to put #10 head on my engine.

This head seems to be #20, so it is turbo. And they could not have machined it to fit 14mm prechambers in a head that needs 15mm. So I think no problem there.

Picture of part number i in the link to onedrive. (Files are bigger than 2MB so they couldn't be uploaded).

Only question that is open:
What kind of prechamber are those in my new #20 head?
For the moment there are 50:50 opinion.

__________________
1989 300D Turbo, w124 sedan, OM603 + 722.3

Section -1.10- 417 in the factory engine manual details the Removal and Install of the prechambers and has all the specific details of the pre chambers. Original prechambers are stamped or machined with number on their top rim surface right near where the rounded tab fits into the groove of the prechamber bore.

the format is "601/07" or "601/17" etc.

Get some carb cleaner down in there and clean and scrape the top surface that is normally under the retaining ring until you can make out the numbers

cho answered the questions. I didn't know whether the #15 head was for turbo or naturally aspirated application. You're ready to go if you have a full set of inclined prechambers, lock rings and injectors to transfer from the #15 head.

Sixto
MB-less

the #15 head is a turbo head so at least the prechambers from any other turbo heads will fit the 15 mm bores but the difference between vertical and inclined would have to be addressed if that is what is available.

looking at the two pictures of his original injectors there is nothing in those pictures that would lead me to assume that it was inclined injection in that #15 head, there are no plastic rings that are originally installed in the inclined installations, and the part of the prechamber lock ring that can be seen doesn't look like the serrated/splined prechamber lock rings either. A good look/picture of the lock ring would help for sure.

I see threads in the prechamber which say inclined to me. Maybe vertical prechambers have those threads also? I don't remember.

Those plastic sleeves are NLA so take care of them if you have them. IIRC they're only job is to keep the splines clean. They get yucky particularly with WVO.

Sixto
MB-less

All the MB prechambers have internal threading ion their inside, that's how they are removed. But the internal threads might be different between the inclined and vertical prechambers , that's why most prechamber puller tools the slide hammer adapter type are 2 in 1 with a different threading on either end, I think.

Oh? Does an inclined injector thread into a vertical prechamber? Can eyes discern whether the internal threads are vertical or canted 5* or whatever?

Sixto
MB-less

No the inclined injector (nozzle holder) threads are fine something like M22 X 1 and the threading on the inside of the vertical prechamber is more coarse than that or visa-versa. The inclined prechamber might be discernible if some one could get a good close up look at the top opening because you can make out that the threading doesn't end square with the imaginary plane across the top of the prechamber. It would need to be clean but and someone would have to be close to see it with their eye but a decent camera could probably get a picture of that. I've got a box of prechambers somewhere if I get a chance I'll see if I have both and maybe get a picture, even just for future reference. Of course with the lock ring removed you could probably see the numbers on factory prechambers.