Angled Injector Thread Pitch

[OM616]

I did a quick search and could not find any posts that identified the thread pitch on the new style "angled" injectors.

I am modifying a straight injector PC to make it an angled injector PC for my 616, and if the threads are compatible with my approach, I would like to use a standard thread, (my current plan is to modify the injector body with a thread of my choice).

I am trying to keep from buying one just to find out the thread dia is too big.

thanks.

[tomnik]

Can you explain more detailed what you intend to do?
Basically the thread is IN the angled PC and not in the separate PC fixing thing as it is on the "old style".
A 616 engine can be upgraded with angled PCs. There is one single type of PC that fits.
On 60x engines the PCs are special. The glow plug hole is different.

Angled injectors on 616: change PCs and injectors
Angled injectors on 617 turbo: way more complicated. The PC shape is different.

I have a picture of a disassembled PC.

Tom

[OM616]

Originally Posted by tomnik

Can you explain more detailed what you intend to do?
Basically the thread is IN the angled PC and not in the separate PC fixing thing as it is on the "old style".
A 616 engine can be upgraded with angled PCs. There is one single type of PC that fits.
On 60x engines the PCs are special. The glow plug hole is different.

Angled injectors on 616: change PCs and injectors
Angled injectors on 617 turbo: way more complicated. The PC shape is different.

I have a picture of a disassembled PC.

Tom

The angled PC that will fit the 616 is expensive and I wanted to come up with a way, short of making a new PC, to have an angled PC for the 617 as well. So I am playing with a 616 PC to see how practical the concept is.

I am basically going to make the upper portion of the stock PC, (where the injector goes), solid and machine an angled bore and new seat.

If I turn down the course threads and cut new treads in the injector housing end, I can get up to 7 degrees of angle. This however requires the use of only these injector bodies. I am wondering what the major diameter of the stock angled injectors is, as that diameter determines the max angle I can get.

I was just wondering what the injector thread diameter and pitch is of the angled injector / PC so I can determine if a standard injector will work. That would allow the use of stock injector bodies, although I think I remember something about the line nut threads being different between the 61X straight and the 60X angled injectors. If that is indeed the case, then I will just modify the stock 61X injector bodies.

[tomnik]

maybe this helps:

http://fmso.de/forum/messages/255412.htm

The angled thread is in the PC this is why you need the thread of the injector at the very low end.
On 617 the PC has no thread for the injector.
Maybe I misunderstood: you want to angle the thread on the injector??

I believe it is M22x1.5

Tom

[OM616]

What I am going to do is make a 617 injector look like a 60X injector. To do this, I will first machine off the 617 threads. Then I will cut new threads into the injector body at the tip, just like the 60X injector.

For the PC, I will make the injector area solid, and machine in new injector threads on an angle, and of coarse a new seat for the injector heat shield to seal against.

When finished, the injector will thread into the angled PC. I will need to modify the 617 lock collars, or buy 60X collars for installation.

I wish I knew what the language spoken in the link. I would like to understand how the duel stage injector works and what the differences in the internal parts do to the operation.

I am really considering going with dual stage injectors on the next 10mm MW I build and would like to have a better understanding of how they work to determine if they will do what I want. I have been very pleased with the modified injectors in the Gen I 10mm set up, but I am curious if there are improvements that can be had with a dual stage injector.

[tomnik]

Let's discuss dual stage injectors separately, I have them installed in my SD.
Language is German.

The reason why I don't like your plan of new thread on 617 injector body is that you can not use the heat shield plates any more. Means these you also need to do custom.
Can't you just cut off the upper part of old angled 60x PCs and weld them to the rest of the cut 617 PC?
I made a thread ring with the 60x thread, machined off the thread of the 617 body as well as a step and pushed the ring on, fixed it by welding.

Tom
(this was how I put dual stage injectors to a angled PC).

[OM616]

Originally Posted by tomnik

Let's discuss dual stage injectors separately, I have them installed in my SD.
Language is German.

The reason why I don't like your plan of new thread on 617 injector body is that you can not use the heat shield plates any more. Means these you also need to do custom).

I will have to turn down the outer diameter of the heat shield just a bit for it to fit in the smaller bore, but when looking at the heat shield, the area I will be removing is chamfered, so it is not doing any real sealing anyway.

I am going to use a fine thread (20 to 28 TPI), which will have a thread depth of .030 inches per side max. This will reduce the cross section of the injector housing that will be pressed against the heat shield. With the finer thread, there will be a higher clamp load on the heat shield, so I am thinking that the reduced sealing area will not be a problem.

Originally Posted by tomnik

Can't you just cut off the upper part of old angled 60x PCs and weld them to the rest of the cut 617 PC?
I made a thread ring with the 60x thread, machined off the thread of the 617 body as well as a step and pushed the ring on, fixed it by welding.

Tom
(this was how I put dual stage injectors to a angled PC).

I am not a fan of welding a PC together because of the shock waves and thermal cycles. Additionally I would be concerned about the alloys weld ability quality for such an extreme application.

After reading that you had to press on a sleeve with threads on it, I am sure that the thread OD is larger than I want. I want to keep the thread OD as small as possible which allows me the most angle options.

I'll do a proof of concept in the next few weeks, and I see if I like it or not. It would not be the first time that I through something that I did in the trash.

[tomnik]

sounds not too bad.
But:
a fine thread might suffer from carbon or other pollution

take care that you hit one axis for nozzle/injector, heat shield and heat shield seat AND PC ball. The PC side of the heat shield seat and the heat shield itself should complete the spherical shape of the inner PC.

the remaining thickness of the (threaded) injector lower body transmits the force onto the heat shield. And this "ring" is the contact area to the heat shield.

Tom

[OM616]

I've laid it out in Auto Cad and can go up to 7 degrees. I think I will go with 5.

Making the tooling and good reference dimensions will be the trick, because, as you said, the centerlines have to intersect at the correct point.

If it were easy, everyone would do it!

[tomnik]

Originally Posted by OM616

I've laid it out in Auto Cad and can go up to 7 degrees. I think I will go with 5.

Making the tooling and good reference dimensions will be the trick, because, as you said, the centerlines have to intersect at the correct point.

If it were easy, everyone would do it!

what is the stock angle?
Keep me informed about your progress.

Btw. did someone contact you for pump upgrade with Holly elements?

Tom

[OM616]

Originally Posted by tomnik

what is the stock angle?
Keep me informed about your progress.

Btw. did someone contact you for pump upgrade with Holly elements?

Tom

From the patent info I interpret that 5 degrees is what they went with, but they also claim up to 12 degrees.

Yes, I was contacted, but I do not have my calibration machine completed yet and I promised the shop that is letting me use their back up machine that I would only be working on my stuff. I told him about the shop that was found that would do the 8mm china elements.

If the PC turns out well, I'll post some pictures.

[moon161]

Curious, what does the angled injector get you?

[OM616]

Originally Posted by moon161

Curious, what does the angled injector get you?

From what I can imagine, the aiming of the injector in the direction of swirl helps support the swirl, as apposed to a grater portion of the conical fuel pattern blowing into and against the swirl.

I also think that with the injector angled in such a manner, that there is more clean air presented directly to the nozzle area which would help supply fresh air to the nozzle, (scavenging that area), helping create a more combustible mixture throughout the injection duration.

I could be full of beans too.

I don't care about reduced particle stuff, just trying to take the latest technology to get better performance and fuel efficiency.

[300TODD]

Lots of answers but not to your question (I hate wen that happens to me!)

The answer is: 22mm x 1.5mm pitch

I know because I destroyed the threads in my angled pre-chambers and had to run a tap through them. Do not try to use old style injectors and PC slotted collar nuts with newer angled PCs! I didn't know they were angled and after putting a $1600 rebuilt #17 head on my '87 300TD I didn't want to buy new injectors and thought the only difference was the PC nuts. Wrong! Anyway I was actually able to re-cut the threads and so far they are holding a seal. I tried to find the angled PCs used and new.... not available aftermarket. Some websites claim to have them but the PNs are the same as older version... BS. I didn't even try the dealer.. too scared to know the price. After reading as much as I could find (shoulda done that beforehand!) I kinda doubt that the angled PCs make that big a difference... just a little better mixing of the fuel. Also, if you are doing a custom mod remember to check depth of PC in combustion chamber of your engine... you don't want the piston to hit the PC... it can! Here is a link to some MBZ info on the two PCs: http://w124-zone.com/downloads/MB%20CD/W124/Index/602_603/01General.htm Read 01-416 & 01-417 under "Cylinder heads, precombustion".

[OM616]

Originally Posted by 300TODD

Lots of answers but not to your question (I hate wen that happens to me!)

The answer is: 22mm x 1.5mm pitch

I know because I destroyed the threads in my angled pre-chambers and had to run a tap through them. Do not try to use old style injectors and PC slotted collar nuts with newer angled PCs! I didn't know they were angled and after putting a $1600 rebuilt #17 head on my '87 300TD I didn't want to buy new injectors and thought the only difference was the PC nuts. Wrong! Anyway I was actually able to re-cut the threads and so far they are holding a seal. I tried to find the angled PCs used and new.... not available aftermarket. Some websites claim to have them but the PNs are the same as older version... BS. I didn't even try the dealer.. too scared to know the price. After reading as much as I could find (shoulda done that beforehand!) I kinda doubt that the angled PCs make that big a difference... just a little better mixing of the fuel. Also, if you are doing a custom mod remember to check depth of PC in combustion chamber of your engine... you don't want the piston to hit the PC... it can! Here is a link to some MBZ info on the two PCs: http://w124-zone.com/downloads/MB%20CD/W124/Index/602_603/01General.htm Read 01-416 & 01-417 under "Cylinder heads, precombustion".

Thanks for the link. It showed some features that I have not seen before.

The cost is a big reason why I am modifying the stock PCs, let alone they don’t exist for a 617.

With the 10mm elements, modified nozzles, and modified burn holes, I have changed about every variable that the stock PC was designed around. Given that fuel is going to be in the $5 per gallon range for a while, any improvement in fuel mixture could be worth $$.