injector shims

[mopar440cu]

Ate all the shims in the injectors the same diameter? It seems [MOPAR][/MOPAR]like it.

[ISX]

I can't see any reason they would be different diameters. Thickness is what makes all the difference.

[Mopar1973Man]

The shim should be close to the diameter of the bore so the shims all lay in evenly and the center hole is where the bleed off fuel returns out of the injector. So the diameter has to be the same but ISX is right its the thickness that changes the pop pressure.

[JLandry]

Actually, the center hole isn't needed in the shims. It serves no purpose as fuel exits out the side of the injector body. I'm using solid shims in my injectors right now.The shims are 10mm in diameter. <- CORRECTION: The shims are 8.5mm in diameter. I just measured one.Regards,John L.Sent from my iPad using Tapatalk HD

[mopar440cu]

I have 2injectors with 2 shims in one. Im talking about the small washer looking part under the spring. I am assuming the two stacked together in these injectorss are equal in diameter in the other injectors, correct?

[JLandry]

Correct.They!re all the same diameter.As stated before (for clarity), the thickness of each shim may vary.John L.Sent from my iPhone using Tapatalk!

[mopar440cu]

Correct.

They!re all the same diameter.

As stated before (for clarity), the thickness of each shim may vary.

John L.

Sent from my iPhone using Tapatalk!

John, 4 out of 5 injectors had 1 shim in them, while the remainder 2 had 2 shims ( Or washers to me) stacked one on top of the other. It seemed, by my naked eye, that the shims were almost the same in thickness. One of the single shim ones looking like it might be off by a hair. I was just wondering what they(the Shims) do? I dont understand what "pop" means actually? Im taking it the way you all are telling me is that it is the fuel delivery?

Thanks for your help in understanding this.

Also do you know what the ft/lbs it takes to reassemble them? I think its 32ft/lbs.

[ISX]

John, 4 out of 5 injectors had 1 shim in them, while the remainder 2 had 2 shims ( Or washers to me) stacked one on top of the other. It seemed, by my naked eye, that the shims were almost the same in thickness. One of the single shim ones looking like it might be off by a hair. I was just wondering what they(the Shims) do? I dont understand what "pop" means actually? Im taking it the way you all are telling me is that it is the fuel delivery?

Thanks for your help in understanding this.

Also do you know what the ft/lbs it takes to reassemble them? I think its 32ft/lbs.

They put different washer thicknesses in to get the exact pop pressure that they need. Some injectors can get away with 1 standard size some need 2 different standard size shims. I cleaned JOHNFAK's up for him and they were the stock ones and half of them had 2 shims as well. Oddly enough, if you measured the 2 shims together, their thickness was the same as the 1 shim in the other injectors. I don't know if cummins was out of the single thick shim or what

I made this just now for you.

http-~~-//www.youtube.com/watch?v=sOXmZkpOIY8

[mopar440cu]

They put different washer thicknesses in to get the exact pop pressure that they need. Some injectors can get away with 1 standard size some need 2 different standard size shims. I cleaned JOHNFAK's up for him and they were the stock ones and half of them had 2 shims as well. Oddly enough, if you measured the 2 shims together, their thickness was the same as the 1 shim in the other injectors. I don't know if cummins was out of the single thick shim or what

I made this just now for you.

http-~~-//www.youtube.com/watch?v=sOXmZkpOIY8

ISX, Thank You!! The video was so good even the wife made me show her, seeing she owns a cummins too. We found that quite interesting and informative!!

--- Update to the previous post...

ISX, one more thing what is the ft/lbs needed to reassemble the injector? I think Mopar1973 said 30 ft/lbs, but Im unsure.

[ISX]

Yeah 32 ft lbs, make sure the threads are clean and put a dab of oil on them.

[98whitelightnin]

ISX, where can I find a pop tester and the fittings for our injectors?

[ISX]

ISX, where can I find a pop tester and the fittings for our injectors?

I'll have to dig up where I got the tester later on but I had planned to get a 24V adapter and couldn't find it anywhere. I looked and looked and said screw it. I would start looking for that first..

[JLandry]

ISX, where can I find a pop tester and the fittings for our injectors?

The best place to look for a good deal on one is probably eBay. I watched eBay for awhile and ultimately netted a heavy duty Army surplus injector tester made by Kiene Diesel (a Model DT-1300). It's capable of producing up to 7,500 psi, but mine has a 0-5,000 psi gauge. It came in a nice metal storage case complete with accessories. This illustration shows a sample setup when in use. When testing 24v Bosch injectors, you must use a Miller SPX 8301 adapter. I bought one on eBay also. Best regards, John L.

[98whitelightnin]

I found a few on the bay for $200+/-, some are made in India and use bosch parts and some are made in Dallas and dont say.