Rebuilding injector question

[USN_Green_Addict]

I've pulled my injectors to rebuild. I cannot find information for the direction this part faces. Does the bevel face the nozzle or the inlet of the injector? I don't trust the previous rebuild.

 

[WillWagner]

You do know that just taking an injector apart and re assembling it doesn't constitute a "rebuild", correct? There are a mess of other items/checks that are done during a rebuild, lapping, pop off pressures, dribble tests, spray pattern check. Those cannot be done without an injector tester.

Here is the TM that covers the injector testing and rebuild, it is here in out TM library,

TM 2815-210-34-2-2 Engine, Multifuel, LD-465-1,LD-465-1C, LDT-465-1C, LDS-465-1

TM 2815-210-34-2-1 Engine, Multifuel, LD-465-1,LD-465-1C, LDT-465-1C, LDS-465-1, LDS-465-1A, LDS-455-2 and Clutches.

www.steelsoldiers.com

The section you desire starts on 4-394

 

[USN_Green_Addict]

I'm taking them apart, cleaning the guts and I'm planning on having cummins do the pressure test, adjusting and other injector tests. I appreciate the TM link. However I guess I didn't see the lapping portion.

 

[KN6KXR]

There are enough surplus nozzles around that lapping new ones is cost prohibitive. You just buy new ones. As for cleaning and testing these are pretty low pressure (for injectors). You can buy a bench pop tester for a bit over $100 on fleabay and track down the adapter bits you need. I keep a set of them as spares I have both the shim type bodies and screw adjust type.

 

[WillWagner]

I'm taking them apart, cleaning the guts and I'm planning on having cummins do the pressure test, adjusting and other injector tests. I appreciate the TM link. However I guess I didn't see the lapping portion.

I do not think your local Cummins dealer/Distributor has the correct stuff to pop test the nozzles. I worked for them for 30 years, did fuel stuff. We did not use any pintle style nozzle that had the same type of line that the LDT/LDS uses. An ADS shop might though.

 

[KN6KXR]

If you buy a pop tester off fleabay it's going to be an "India" type. That is to say, the land of plentiful Massey Ferguson tractors, type tester. If you've ever been to India/Pakistan/Afghanistan you'll know the whole place runs on these simple machines (and their simple injectors). IIRC mine came with a metric setup, I got a flare nut from a trashed LDS injector line, and then I had to buy the compression fitting. It's not perfect but it doesn't leak. If I get a minute to dig in my shop box I'll post the part number (if it's there) it was a difficult little piece to find.

I just checked for nozzle availability because this thread got me thinking of it. Looks like White Owl Parts still has nozzle assemblies for $30. For that price why would you pay somebody to lap them? I just save my old ones (sealed in light oil) and throw new in there. Someday if lapping is justified I'll have them available.

 

[USN_Green_Addict]

I do not think your local Cummins dealer/Distributor has the correct stuff to pop test the nozzles. I worked for them for 30 years, did fuel stuff. We did not use any pintle style nozzle that had the same type of line that the LDT/LDS uses. An ADS shop might though.

This was from when I took my injectors to cummins Denver.

 

[USN_Green_Addict]

If you buy a pop tester off fleabay it's going to be an "India" type. That is to say, the land of plentiful Massey Ferguson tractors, type tester. If you've ever been to India/Pakistan/Afghanistan you'll know the whole place runs on these simple machines (and their simple injectors). IIRC mine came with a metric setup, I got a flare nut from a trashed LDS injector line, and then I had to buy the compression fitting. It's not perfect but it doesn't leak. If I get a minute to dig in my shop box I'll post the part number (if it's there) it was a difficult little piece to find.

I just checked for nozzle availability because this thread got me thinking of it. Looks like White Owl Parts still has nozzle assemblies for $30. For that price why would you pay somebody to lap them? I just save my old ones (sealed in light oil) and throw new in there. Someday if lapping is justified I'll have them available.

After reading more I won't be lapping. I have two sets of 2 hole injector nozzles.

 

[KN6KXR]

Found the little compression fitting in my box. The part number is A-250610R2 a simple internet search: https://www.worthingtonagparts.com/...GOVQgQ4PasCBBtB6_i5UbzBXVX44GH4tYOgvUKmFw6LBD

Can't remember the exact difference just that the cheap pop tester was a metric OD and the sleeve is SAE but the delta is very small. You just have to crush it fairly tight but it holds. White Owl has shim kits for the shim type injectors.

Be advised some companies sell "2 hole" injectors that are actually reworked NOS one hole injectors (literally the original part number is stamped over on the injector body). The one hole injectors have a very different nozzle size than the later two hole style. So if you get a set of reworked one hole (that are actually a two hole in a one hole holder), then buy two hole replacement nozzles, they won't fit. I don't think any of the two hole reworked size are available just as a nozzle (but you can still buy the whole injector for about $80). I've been round on this with a few vendors... I gave up found what worked and bought spares for the shelf. Now I have a mix of both. Eastern Surplus and White Owl have the different styles.

It's cheap, simple and enjoyable to service my own injectors at my leisure. Hopefully you find it the same.

 

[USN_Green_Addict]

Found the little compression fitting in my box. The part number is A-250610R2 a simple internet search: https://www.worthingtonagparts.com/...GOVQgQ4PasCBBtB6_i5UbzBXVX44GH4tYOgvUKmFw6LBD

Can't remember the exact difference just that the cheap pop tester was a metric OD and the sleeve is SAE but the delta is very small. You just have to crush it fairly tight but it holds. White Owl has shim kits for the shim type injectors.

Be advised some companies sell "2 hole" injectors that are actually reworked NOS one hole injectors (literally the original part number is stamped over on the injector body). The one hole injectors have a very different nozzle size than the later two hole style. So if you get a set of reworked one hole (that are actually a two hole in a one hole holder), then buy two hole replacement nozzles, they won't fit. I don't think any of the two hole reworked size are available just as a nozzle (but you can still buy the whole injector for about $80). I've been round on this with a few vendors... I gave up found what worked and bought spares for the shelf. Now I have a mix of both. Eastern Surplus and White Owl have the different styles.

It's cheap, simple and enjoyable to service my own injectors at my leisure. Hopefully you find it the same.

I have a spare old injector that I ordered. I need to do a compression test. Do I leave the guts in the injector or take them out?

 

[WillWagner]

This was from when I took my injectors to cummins Denver.

Upper left corner. United Technologies Fuel Systems div tested them. If you took the injectors to Cummins in Henderson, they farmed them out to UT for testing.

 

[KN6KXR]

I have a spare old injector that I ordered. I need to do a compression test. Do I leave the guts in the injector or take them out?

It's basically a one way valve so you have to take the pintle out of the injector at a minimum. Probably the nozzle and the guts of the unit for better flow. The pressure tester has a check valve.

I haven't done this yet as my engine runs smoothly and hasn't called for me to do it (also I have way too many trucks that NEED broken stuff fixed). When you find the adapter and parts needed please post them it's on my list!

 

[USN_Green_Addict]

Upper left corner. United Technologies Fuel Systems div tested them. If you took the injectors to Cummins in Henderson, they farmed them out to UT for testing.

That was a paper I printed off so cummins could see the correct pressure