LB7: Injector Cup/Copper washers

TimAT

New member
Aug 26, 2010
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0
After pulling the injectors again, I noticed the copper washers don't appear to be making any contact with the cup and injector. Are they supposed to seal the injector to the bottom of the cup? I measured the old ones at .078 to .079 and the new ones are exactly the same thickness. Had carbon on both sides too. I measured the distance on the injector from the lip to the flat at the tip and the bottom of the cup plus the copper is still more than the injector.

Any ideas?
Anyone have an injector out that could measure the depth from the top of the cup to the bottom?

I've sent all the injectors back to have them checked so I do have a little time before they get back.
I didn't have any issue with the cups pulling either, they're still there from the factory's installation, and are flush with the heads on top.
 

TimAT

New member
Aug 26, 2010
11
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Yep. They were spotless. All the coppers just fell off and stayed in the cups. Picked them out with a hook. No marks on either side to indicate they were even a little tight between the cup and the injector.
No signs of compression in the cups which is good, but the fact there's a difference in measurement between the length of the injector and the distance between the top of the cup and the copper has me a little puzzled.:confused:
 

rcr1978

Active member
Apr 1, 2007
790
26
28
Spring Creek, NV
How about a little history about the injector's? Did you buy new ones somewhere? Some places that rebuild injectors use Dipaco nozzles and not Bosch, could have been a screw up somewhere and possibly the nozzles are to short. :confused:
 

TimAT

New member
Aug 26, 2010
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Original injectors made it to 132k then filled the oil pan with fuel. Got a set of remans from Pensacola (yes, I know), installed and had a miss right off the bat. Pulled them again to double check everything, replaced the o-rings and coppers again. Reinstalled, and still have a miss.Pulled them again, sent them to Pensacola for them to test. Called them today and they said all 8 were fine and on the way back to me. When I bought the truck in 01, I bought the GM service manuals. Everything installed and torqued per the specs in the manuals.
 
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rcr1978

Active member
Apr 1, 2007
790
26
28
Spring Creek, NV
Send them back and tell them u want your money back and buy bosch remans, dont waist your time with them. It sucks you already have done this 2 times now it will be atleast 4 if you put those pieces of chit back in. :( I'm betting that the nozzles are not bosch look at them when you get them back. I guess you can say they false advertise about there remans because I called and they said they use 100% bosch reman parts wich is a lie.
 
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Jdeharo

New member
May 22, 2016
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I'm getting ready to install new injectors and copper washers.
Does it matter what side the washer goes in, one side has a little dome, the other side is almost flat.
 

JG_2004DM

New member
Sep 14, 2024
1
0
1
Santa Cruz Mountains, CA
Hi Tim, I have the same observation - the new are about 0.001" thinner than two I removed from our 2004 DM at 93k miles. The injectors do not appear to have carbon up the sides, so I am thinking the washers sealed a bit. Just concerning to put even thinner in. Anybody have recommendations?