New truck knocking....

[GreenF350]

Ok, I know I have post up all over this place for different problems or questions, but I am diesel retard (But an competent gas mechanic). I bought a 2000 F350 w/133,000mi a few weeks ago and all was well, I love the truck but just recently started hearing a knocking noise from the engine. I took it in to a reputable repair shop and he came out and listened and hooked up the scan tool and did all the injector tests. (All free of charge) He said that everything was passing the tests, but he heard the noise too and wasn't sure at that point what it was. Said he THOUGHT the exhaust might not quite sound right, but I can't hear anything wrong in the exhaust and neither can any of my fellow gearhead friends. I have run a full bottle of Redline Diesel Catalyst through it, changed the oil/filter, changed the fuel filter (and "primed" with the diesel catalyst from above). It sounds just like a little elf is hitting the engine with a hammer. Sounds like once per revolution (same "pace" as injectors). It is barely, if at all noticeable when cold and gets louder as it warms up. Most moticeable at idle, but can hear it at lower throttle positions.

Is it possible this is still just a clogged/bad injector or do I have bigger problems looming on the horizon? Any suggestions to find the problem on my own or should I just take it back to this guy? Any help would be appreciated, I am starting to wish I had bought a gasser. Thanks.

-Aaron

[pipelayerjdh]

Does it sound like it is coming from one general direction?

[Turbodude]

its a diesel silly! just kidding but mine does that when its cold and goes away when it warms up...you may just had to go out and spank it for being bad...go out and run the bejesus out of it...i like to drop it down into second and take it up to 3K for a while and that usually cleans things out

[GreenF350]

Originally Posted by pipelayerjdh

Does it sound like it is coming from one general direction?

Hard to tell for sure, but mostly the drivers side rear....Middle to top of engine. I'm starting to think maybe I just have the "cackle" I keep reading about on my searches. Anybody know of a good way to find out FOR SURE if that is the source? I don't really care about noise, just don't want the thing to come apart on me.

-Aaron

[~CrazyDiesel~]

Funny I get to use this link twice in 5 minutes....

Does it sound anything like this? ( this is a severe example )

[GreenF350]

Yup, Sure does...Not quite as bad, but sounds exactly the same as far as I can tell. I guess I have it then. At least it's not as bad as I was afraid it was.

[bobo510]

I have the same problem on an 01 F350. Sounds exactly like the audio sample. Is it an injector problem? I am trying to sell the truck then it starts knocking. Sucks!

[GreenF350]

From my research basically it is a problem of bad design on Ford's part. The make a couple different kits that are supposed to help.....Hutch mod and a return style fuel system are supposed to make a big difference. I haven't had a chance to try any of them....Mine is still "knocking" when warm. Runs great though and I am almost sure that that is my problem. Good luck.
-Aaron

[PHILS GOOD]

Im glad someone else has posted this thread, I thought it was just my truck. I have an 02 7.3 with 78,000 and it is making the same sound. I have considered having a ford tech look it over but every time i ask some one they say its just a diesel,

it doesnt do it when cold only when warmed up and in park, its kinda unnerving.

when i had my 4" exhaust installed ( magnaflow ) the installer told me it would knock more, but my god its loud

If any one pinpoints this please let me know also

[~CrazyDiesel~]

Always keep in mind, i am not a ford technician please, so everything said by me, is by my opinion, and what i have learned personally.

99% of all 7.3Ls have that #8 "knock" some have it worse than others, some it's just barely audible, (like mine, and then it cackles some around 1500 rpm and mild load)

All of our trucks seem to go (imagine the ticks are the engine idling)


tickticktickticktickticktickTickticktickticktickti ckticktickTicktickticktickticktickticktickTick

But, when you have excessive cackle, like in the audio file, that is casue for concern, because a large amount of air IS getting into that #8 injector, and the air is coming from somewhere, the most common place being th e fuel pump inlet, the fuel filter drain o rings can also cause it too i believe.

I dont believe the exhaust is causing it to knock more persay.

I am about to fall asleep right now, sop i'll foll
ow up on this tomorrow evening