injector o-rings??

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Aug 25, 2008 | 11:59 AM

#16

kent's f-350

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From: northern indiana

ok thanks, yes it is burn'n oil.

Aug 25, 2008 | 02:12 PM

#17

spinge

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From: Carroll County, MD

OK, then here are my thoughts on how to figure out where the black stuff is coming from:

Drain the black stuff out of the fuel bowl, then with the filter cover on, put a piece of tubing on the fuel drain line, into a clear container, and then open the lever and turn the key on (don't start). You should then be seeing the fuel from the tank - you may need to let it run for a little bit to flush the last bits of filter bowl crud you mentioned.

If it is black and cruddy, then the problem is from the tank, and you will probably need to go the route of dropping and cleaning the tank.

If, on the other hand, the fuel runs clean, then Kris is probably right on the money about an injector leaking past an oring. I am not sure if installing (temporarily) a fuel pressure gauge (as shown on other threads around here) would show a spike or excess fuel pressure, from the high pressure bleed-by of the oring, but it might.

Hope this helps

Aug 26, 2008 | 10:37 PM

#18

spinge

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From: Carroll County, MD

Bump

Any luck yet Kent?

Sep 7, 2008 | 09:44 PM

#19

kent's f-350

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well i changed my o-rings and did the fuel tank mod. and no more BLUE SMOKE!!! BUT now when i start it (cold or hot) the rpm's surge up and down until it bump the fuel pedal? any thoughts??? still kind of doggy, but i think the injectors are just dirty yet, we'll find out in a few days.

Sep 7, 2008 | 09:48 PM

#20

kent's f-350

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From: northern indiana

and i put a fuel psi gauge on the fuel bowl drain line,and it's running 58 psi, is that right?? i thought the by-pass was set at 30 psi??

Sep 7, 2008 | 10:10 PM

#21

spinge

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From: Carroll County, MD

Quote:

Originally Posted by kent's f-350

Sounds like you got the romps (at least what I think is called the romps) How much have you run it since the fix? Air in the rails can cause this, and the best way to get all of the air out is take it out and run it like you stole it. I have heard tell of needing about 100 - 200 miles to purge the air. Mine was not as long, but was still about 50 or so miles.

Were you able to find a reason for the crud in the fuel bowl?

The fuel pressure sounds about right, but I am not sure if it should be that high in the return line - hopefully others will chime in.

Sep 7, 2008 | 10:32 PM

#22

kent's f-350

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From: northern indiana

well i just started it today and have less than 30 mi on it so, we'll see in a few days.
and yes the crud was coming from the bad o-rings. the fuel tank even had a lot of motor oil mixed in with the fuel.