6.9 idi injector return cap leaks

Kdo58

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The hoses are larger so it has less pressure on the return caps, but you will have to make a adapter to replace the one near the back of the motor, which goes back to the fuel tank.
 

Cole_Sudeyko

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Just a different co figuration of caps. Tees and elbows in different spots. Same diameters for O rings.

What are you lubcricating your o rings with? I will either buy a harbor freight box of misc o rings, or get a set from a vendor, and I lube them up with a glob of vaseline. Rarely have one leak.
I was just using some lubriplate assembly grease
 

asmith

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Try vaseline. that has seemed to work the best for me. Also I haven't seen it mentioned yet, and maybe you are already doing this, but just in case. put the top oring on first then GENTLY roll the bottom one over it into the bottom groove. This can help prevent them from getting nicked.
 

Cole_Sudeyko

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Try vaseline. that has seemed to work the best for me. Also I haven't seen it mentioned yet, and maybe you are already doing this, but just in case. put the top oring on first then GENTLY roll the bottom one over it into the bottom groove. This can help prevent them from getting nicked.
I’ll give that a try thank you!!
 

Nero

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Vaseline, and Super Lube synthetic grease are what most people use.
 

scsmith42

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I use Dupont Molykote 55 o-ring grease with all hydraulic and fuel system o-rings. It's made specifically for lubricating 0-rings.

Although I buy it from my local industrial supply house, it's available on Amazon.

 
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nelstomlinson

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CDD and R&D both sell return kits that should be the best quality available.
Dregs Garage occasionally makes a run of very nice brass return caps. I've had excellent success with those, but they're expensive, and shouldn't be necessary.
 
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