7.3 Injector o-ring question

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Jul 14, 2019 | 02:54 PM

Pat.hayden73

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From: LaGrange, Ky

7.3 Injector o-ring question

I have been dealing with oil pressure issues after installing rebuilt injectors. Today i pulled the valve covers to inspect for oil leaks. Is it normal to have small drips of oil coming from what i call the back side of the injector ( side with out the the plug harness )? This forum has already been a huge help!!! Also issue with pressure gets worse after its warm. Cold she starts right up and runs great. After warm she looses power and will stall at times if i don't have my foot on the fuel pedal a little. Also had it put on a scanner and shows 350psi during crank when warm. Thanks!!!!

Jul 14, 2019 | 03:37 PM

z31freakify

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From: Las Cruces New Mexico

Could be as simple as bad IPR O rings since you mention it does it only when warm.

Jul 14, 2019 | 03:40 PM

Pat.hayden73

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From: LaGrange, Ky

IPR is less than a year old replaced with a unit from motorcraft. I also should had said I tried unplugging the ICP and she falls on her face when doing so. When we did the scan test to find out pressure the IPR was running at 60% thoughts are it was running like that to keep her running.

Jul 15, 2019 | 01:05 AM

aawlberninf350

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From: Elk Grove, CA

IPR running 60% duty cycle means it's supplying all the oil it can. 350 psi ICP when warm is not satisfactory.

If you see oil popping up Jed Clampett style from around the injector, plus the low psi, I'm thinking an o ring got rolled on installation.

Also check oil level. If it's gone up then fuel has been going into the oil.

Jul 15, 2019 | 06:55 AM

Tugly

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From: Puget Sound

That hole on the side of the injector is a weep hole... a trickle is normal. This sounds like a classic rolled O-ring on installation, a search for "Cody test" will reveal some help here.

Jul 15, 2019 | 08:39 PM

Pat.hayden73

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From: LaGrange, Ky

Thanks for the replies!!! I tried the "Cody test" Today however i could only get around 120psi damn regulator stuck on my compressor. I ran the test with Valve covers on originally fairly sure i heard a little something gurgling. After pulling covers tried again and couldn't hear much of anything. I did this by pulling the lines off the HPOP and did each head individually. However i did notice something different from the other day, a few days ago i did a fresh oil change with 14 quarts. Now my dipstick is showing over full probably a good 3/4 - 1" over the full mark. So now i'm guessing it looks like a middle O'ring issue. Any other ideas???? Thanks again!!!

Jul 16, 2019 | 12:57 AM

aawlberninf350

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From: Elk Grove, CA

I'm thinking the oil level is going up because the fuel is getting pumped into the crankcase because, as you suspect, the injector o rings are compromised. IMO time to pull all the injectors, put a fresh set of o rings on, and re-install. New copper crush washers would be good. And a rubber mallet possibly. Lay a straight edge across the solenoids to make sure they are all fully seated.

Dip the sticks in oil to make sure they are lubed.

Cheap fix!