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Engine How to properly seat injectors and O Rings

  • Thread starter Thread starter 93silverlx50
  • Start date Start date Jun 12, 2018

93silverlx50

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Jun 12, 2017
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#1
  • Jun 12, 2018
  • #1
So I think I have a leak from an injector I reinstalled after my motor swap at cylinder 4, under the FPR. With the motor running, I had a decent leak. I pulled the coil wire and cranked the motor getting good fuel pressure. I could not get it to leak without the motor actually running. I put both new o rings on the injectors and then seated them in the fuel rails then into the intake. I was told the proper way is to put the o rings into the fuel rails (lubbed) then seat the injectors into the rails and then push the rails down into the intake. Does that sound right?
 

jrichker

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  • Jun 13, 2018
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The lower intake manifold O rings get a coat of Teflon pipe dope and then you "stretch & roll" them onto the injector body.
The upper O rings get dipped in motor oil and then you "stretch & roll" them onto the injector body. After that, put the injectors into the lower intake manifold and wrestle the fuel rails in place. I say wrestle because just about the time you get one injector in place another one will pop out of the fuel rail...

Put the pintle caps in boiling water to soften them for easier installation.
 

96pushrod

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  • Jun 13, 2018
  • #3
jrichker said:
The lower intake manifold O rings get a coat of Teflon pipe dope and then you "stretch & roll" them onto the injector body.
The upper O rings get dipped in motor oil and then you "stretch & roll" them onto the injector body. After that, put the injectors into the lower intake manifold and wrestle the fuel rails in place. I say wrestle because just about the time you get one injector in place another one will pop out of the fuel rail...

Put the pintle caps in boiling water to soften them for easier installation.
Click to expand...

Hmm the pipe dope part sounds interesting, never heard that before. I always just used a little oil for both orings lol.

Seating the injectors isn’t that tough. Just push and wiggle like hell and they’ll seat in there. You may have pinched an oring if it leaks.
 

93silverlx50

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Jun 12, 2017
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#4
  • Jun 15, 2018
  • #4
Thanks for the input. I removed the fuel rails and all the injectors. I noticed 1 pintle cap was cracked so I replaced that and relubbed all the o rings. I put everything back together and noticed that the fuel line that hooks into the fuel rail was being pushed up with the 90 degree blower inlet tube and the tall valve covers I went with. I did some adjusting and its fitting well now and no gas leaks.
 
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