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Injector shim

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Old Sep 14, 2012 | 05:45 AM
  #1  
rLmcowboy's Avatar
rLmcowboy
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Injector shim

I have 3 injectors that I need to shim to get desires pop pressure. Any ideas where I can buy some. I don't have any old extra injectors to use for parts
 
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Old Sep 14, 2012 | 09:17 AM
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86f350
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you need to find old core injectors. Ive heard of some ppl using washers from a hardware store with decent luck. remember + or - .001 thickness is equal to + or - 50lbs of pressure.
 
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Old Sep 14, 2012 | 10:13 AM
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Shims

Originally Posted by 86f350
you need to find old core injectors. Ive heard of some ppl using washers from a hardware store with decent luck. remember + or - .001 thickness is equal to + or - 50lbs of pressure.
Yes your are right about shim thickness and corresponding pressure. I would just like to add the pressure to look for after shimming is 1800 to 1950 PSI...but I'm sure everybody knows that...
 
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Old Sep 14, 2012 | 02:03 PM
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You can use a washer or stack washers if you want. Just make sure they have a hole in the middle. To adjust the thickness of the washer, you can lap it on some fine sand paper on top of a piece of glass. You may want to use some oil for the final lapping.

I have looked for sources of injector shim kits and any that I found were expensive.

This is your quick answer:
https://mercedessource.com/node/5287

Maybe these guys can offer something:
SUN DIESELSYSTEMS - Injector Nozzles
 
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Old Sep 14, 2012 | 03:44 PM
  #5  
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turtlemann14
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could always tear up a set of feeler gauges.
might be fun to poke a hole in them though
 
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Old Sep 14, 2012 | 05:16 PM
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hey Eatont9999

would that help in my situation?

can you lower the opening pressure with shims or just increase it?

you know if my lift pump/ip is weak can i get the injectors to open at a lower pressure or no??

thanks
 
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Old Sep 14, 2012 | 05:33 PM
  #7  
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Pressure

Originally Posted by linus72
hey Eatont9999

would that help in my situation?

can you lower the opening pressure with shims or just increase it?

you know if my lift pump/ip is weak can i get the injectors to open at a lower pressure or no??

thanks
I think if you get around 1400 psi or less the injectors won't work....as far as lowering pressure using shims...I don't think so...The idea behind shims is to make a weak spring stronger...so to speak...

Hope that helps ya..
 
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Old Sep 14, 2012 | 05:58 PM
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1475 is minimum psi 1800-1950 is ideal.and thanks for all the info
 
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Old Sep 16, 2012 | 07:20 PM
  #9  
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greywynd
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Huh....I have enough shim stock and tools to make these I should go into business....what's the ID and OD of the shims?
 
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Old Sep 17, 2012 | 09:48 AM
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Originally Posted by linus72
hey Eatont9999

would that help in my situation?

can you lower the opening pressure with shims or just increase it?

you know if my lift pump/ip is weak can i get the injectors to open at a lower pressure or no??

thanks
In your situation, I think messing with the injectors would only make things worse and cost you more money and time. In theory, yes, if you have a weak IP, lowering pop pressure may help the injectors fire but you will also be advancing the timing and atomization will be much less. Then, you still have a weak IP with limited life.

I really don't think the IP is to blame. Update your current thread once you have tried a few more things that have been suggested.


Also, if you have a shim punch tool, you can make shims out of sheet metal. Feeler gauges are good to use because you already know what size you have.
 
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